Discussion:
SFPD needs to crack down on Bicyclists with No Lights (& SF-GG Bridge-Larkspur Ride Report)
(too old to reply)
SMS
2008-11-23 16:15:37 UTC
Permalink
Yesterday we rode from the Presidio in San Francisco over to Larkspur,
and took the ferry back to San Francisco. By the time we finished eating
a late lunch/early dinner at Taylor's Automatic Refresher, it was 5:30
and dark, as we rode along the Embarcadero back to the Presidio.

It was fine until Aquatic Park, where the lighted streets ended. I had
lights for everyone so it was no problem for us, but with the fog and
darkness it was _really_ hard to see other bicycles, and there were _a
lot_ of them, nearly all from those bicycle rental places along
Fisherman's Wharf (identifiable by the handlebar bags).

The rest of the ride back was not too enjoyable, having to strain to see
shadows of cyclists, dressed in non-reflective clothing, coming toward
us in the darkness and light fog.

One cyclist complained "you're blinding me" due to my light, which was
just a two AA Cree LED flashlight (Fenix L2DCE) attached to my handlebar
("Loading Image..."). I angled it down a
bit after that, but geez it's only a 3W LED.

Anyway, I think that these rental places should be providing at least
"being seen" front and rear lights on their bicycles at this time of
year, and that SFPD should enforce the laws on bicycle lighting,
especially in areas with no street lighting.

BTW, if you take visitors on the classic ride across the GG bridge and
take the ferry back, I recommend going all the way to Larkspur, rather
than coming back on the Sausalito or Tiburon ferries. First, you can eat
at the Marin Brewing Company right across the road from the Larkspur
ferry terminal (use the pedestrian overpass) which is much better than
those tourist traps in Sausalito or Tiburon. Second, you get a much
longer Bay Cruise than from Sausalito or Tiburon. Third, the Sausalito
and Tiburon ferries are typically packed with all those people on the
rental bicycles (as well as hordes of other tourists), but almost no one
goes all the way to Larkspur, which is really not much further than
Tiburon, and it's a nice route. There were only eight bicycles on the
boat yesterday, and less than a hundred passengers on a boat that holds
750 people.

The Sausalito-San Francisco ferry can get nasty when it gets crowded.
Last time I rode it the bar ran out of vodka for Bloody Marys and irate
tourists threw the bartender overboard. I think one of the reasons for
so many of those rental bicycles being out so late is that the number of
bicycles on the ferries is limited, and it was a really nice day
yesterday so a lot of tourists had the same idea of a ride to Sausalito
and back by ferry (which the bicycle rental companies promote). I'd
wager that a lot of bicyclists were denied boarding and decided to ride
back.

I tried to exit the Larkspur-San Francisco ferry with a Surly Long Haul
Trucker with Arkel panniers, but the owner stopped me.

The route to the Larkspur ferry terminal is now signed pretty well,
which is good since it's not an obvious route, with some disconnected
bike paths to Corte Madera and Larkspur, that you pretty much have to
use to avoid 101 unless you go a really long and hilly way around.

Taylor's Automatic is a good place to eat where you can lock your bikes
to the railing around their outdoor patio, and you can see your bikes
even from inside the restaurant. Try the pistachio milk shake.
"http://www.taylorsrefresher.com/menu/TaylorsMenuFall2008.pdf"
ZBicyclist
2008-11-23 17:55:22 UTC
Permalink
Post by SMS
Anyway, I think that these rental places should be providing at least
"being seen" front and rear lights on their bicycles at this time of
year, and that SFPD should enforce the laws on bicycle lighting,
especially in areas with no street lighting.
Rental bikes that I've seen (but I'm not in the bay area) tend to
have little attached to them of value that could be removed easily.

But those Halloween blinkies they give out near trick or treat time
have to be
1. Cheap
2. Pretty be-seen visible
3. Since they are yellow, they'd be acceptable either front or rear.
Heck, real estate agents give them out free, as an advertising
gimmick.
Tom Keats
2008-11-23 18:49:57 UTC
Permalink
Post by ZBicyclist
Post by SMS
Anyway, I think that these rental places should be providing at least
"being seen" front and rear lights on their bicycles at this time of
year, and that SFPD should enforce the laws on bicycle lighting,
especially in areas with no street lighting.
Rental bikes that I've seen (but I'm not in the bay area) tend to
have little attached to them of value that could be removed easily.
But those Halloween blinkies they give out near trick or treat time
have to be
1. Cheap
2. Pretty be-seen visible
3. Since they are yellow, they'd be acceptable either front or rear.
Heck, real estate agents give them out free, as an advertising
gimmick.
Riding in fog at night is tricky business.
So much so, I prefer not to do it. Sometimes thick
banks of fog can just swallow yellow->red (i.e:
longer wavelength) light. And passive reflectives
don't work very well in thick fog. Fog is the
one weather condition that actually fights against
your illumination system.

AFAIC foggy nights are for watching TV at home,
or making a batch of stew or clam chowder.


cheers,
Tom
--
Nothing is safe from me.
I'm really at:
tkeats curlicue vcn dot bc dot ca
SMS
2008-11-23 20:31:16 UTC
Permalink
Post by ZBicyclist
Rental bikes that I've seen (but I'm not in the bay area) tend to
have little attached to them of value that could be removed easily.
They do provide handlebar bags, and all the bikes have rear racks.

During times of year when it gets dark before the rental place closes
they should include an LED headlight and tail light in the bag that can
be attached without tools. The rental agreement should include a
requirement that the rider use the lights after dark.

Maybe charge something extra if the bicycle is returned after dark to
cover the cost. Maybe seal it inside a pouch and only charge if the
pouch is opened. I don't know, they can figure it out.

Their insurance company would not be too pleased if they knew that they
were renting bicycles that even if returned by the closing time are
being operated in an illegal manner that could cause the rider injury
and also expose the rental agency to liability from anyone that rider
might injure.

What would be great is if they had wheels with dynamo hubs, and dynamo
lights on all the rental bicycles, but obviously that's not going to happen.
nmp
2008-11-23 22:05:46 UTC
Permalink
Post by SMS
During times of year when it gets dark before the rental place closes
they should include an LED headlight and tail light in the bag that can
be attached without tools. The rental agreement should include a
requirement that the rider use the lights after dark.
Why not properly mounted (bolted on) head and rear lights, powered by hub
dynamo. If they can't raise the rental fee, at least it will improve the
resell value of the bikes. Those are probably sold after 1-2 years of
service anyway.
Tom Kunich
2008-11-23 21:33:59 UTC
Permalink
Post by SMS
The rest of the ride back was not too enjoyable, having to strain to see
shadows of cyclists, dressed in non-reflective clothing, coming toward us
in the darkness and light fog.
So you made it back and are complaining because you had to be careful.
nmp
2008-11-23 22:09:22 UTC
Permalink
Post by Tom Kunich
Post by SMS
The rest of the ride back was not too enjoyable, having to strain to
see shadows of cyclists, dressed in non-reflective clothing, coming
toward us in the darkness and light fog.
So you made it back and are complaining because you had to be careful.
Perhaps he's complaining because he saw so many people exposing
themselves to danger, riding without lights. Proper bicycle lights are no
luxury. In a lot of countries they are mandated by law.
Tom Kunich
2008-11-23 22:34:06 UTC
Permalink
Post by nmp
Post by Tom Kunich
Post by SMS
The rest of the ride back was not too enjoyable, having to strain to
see shadows of cyclists, dressed in non-reflective clothing, coming
toward us in the darkness and light fog.
So you made it back and are complaining because you had to be careful.
Perhaps he's complaining because he saw so many people exposing
themselves to danger, riding without lights. Proper bicycle lights are no
luxury. In a lot of countries they are mandated by law.
On the bike path......
Richard Mlynarik
2008-11-23 23:20:05 UTC
Permalink
Post by Tom Kunich
Post by SMS
The rest of the ride back was not too enjoyable, having to strain to
see shadows of cyclists, dressed in non-reflective clothing, coming
toward us in the darkness and light fog.
So you made it back and are complaining because you had to be careful.
Sounds like a simply horrible experience. Just horrible.

Why no citizen's arrests of the miscreants?
Surely that would have been the least you could do.

You ought to have U-locked them to your Surly Long Haul Trucker,
covered their heads in Arkel panniers to prevent escape,
used your AA Cree LED flashlight to illuminate your Garmin
GPS unit to locate coordinates that you could communicate
at high priority to the San Francisco Police Department
Flash Response Units using your iPhone Mobile Communications
Center, and awaited Action by the Authorities.

We do regret that you did not fully enjoy your visit to
San Francisco and trust that our Customer Care Response
Team will have fully effectuated feedback-driven improvements
to our customer-facing experience by the time you make your
next visit. As a token of our regret, please accept this
Bloody Mary coupon, good on your next ferry ride to San
Francisco.
j***@stanfordalumni.org
2008-11-24 02:02:31 UTC
Permalink
Post by SMS
Yesterday we rode from the Presidio in San Francisco over to
Larkspur, and took the ferry back to San Francisco. By the time we
finished eating a late lunch/early dinner at Taylor's Automatic
Refresher, it was 5:30 and dark, as we rode along the Embarcadero
back to the Presidio.
It was fine until Aquatic Park, where the lighted streets ended. I
had lights for everyone so it was no problem for us, but with the
fog and darkness it was _really_ hard to see other bicycles, and
there were _a lot_ of them, nearly all from those bicycle rental
places along Fisherman's Wharf (identifiable by the handlebar bags).
The rest of the ride back was not too enjoyable, having to strain to
see shadows of cyclists, dressed in non-reflective clothing, coming
toward us in the darkness and light fog.
One cyclist complained "you're blinding me" due to my light, which
was just a two AA Cree LED flashlight (Fenix L2DCE) attached to my
handlebar ("http://nordicgroup.us/s78/images/IMG_0332.JPG"). I
angled it down a bit after that, but geez it's only a 3W LED.
My laser pointer is less than 1W but is greatly blinding. Why aim a
light at the face of oncoming people unless it is a gesture of self
righteous pride. I met a guy on the Dumbarton bridge yesterday with
two of those lights aimed right in my face. He used your excuse about
how few watts they emitted.
Post by SMS
Anyway, I think that these rental places should be providing at
least "being seen" front and rear lights on their bicycles at this
time of year, and that SFPD should enforce the laws on bicycle
lighting, especially in areas with no street lighting.
Did you consider a citizens arrest of unlit pedestrians you met? Hell
They are even worse because they have no metal reflecting bicycle.

Jobst Brandt
Tom Keats
2008-11-24 04:15:20 UTC
Permalink
Post by j***@stanfordalumni.org
Post by SMS
Yesterday we rode from the Presidio in San Francisco over to
Larkspur, and took the ferry back to San Francisco. By the time we
finished eating a late lunch/early dinner at Taylor's Automatic
Refresher, it was 5:30 and dark, as we rode along the Embarcadero
back to the Presidio.
It was fine until Aquatic Park, where the lighted streets ended. I
had lights for everyone so it was no problem for us, but with the
fog and darkness it was _really_ hard to see other bicycles, and
there were _a lot_ of them, nearly all from those bicycle rental
places along Fisherman's Wharf (identifiable by the handlebar bags).
The rest of the ride back was not too enjoyable, having to strain to
see shadows of cyclists, dressed in non-reflective clothing, coming
toward us in the darkness and light fog.
One cyclist complained "you're blinding me" due to my light, which
was just a two AA Cree LED flashlight (Fenix L2DCE) attached to my
handlebar ("http://nordicgroup.us/s78/images/IMG_0332.JPG"). I
angled it down a bit after that, but geez it's only a 3W LED.
My laser pointer is less than 1W but is greatly blinding. Why aim a
light at the face of oncoming people unless it is a gesture of self
righteous pride. I met a guy on the Dumbarton bridge yesterday with
two of those lights aimed right in my face. He used your excuse about
how few watts they emitted.
Post by SMS
Anyway, I think that these rental places should be providing at
least "being seen" front and rear lights on their bicycles at this
time of year, and that SFPD should enforce the laws on bicycle
lighting, especially in areas with no street lighting.
Did you consider a citizens arrest of unlit pedestrians you met? Hell
They are even worse because they have no metal reflecting bicycle.
Pedestrians are only going at an average rate of 2.5 MPH.

Encountering unlit riders on a foggy, rainy, or even
a clear night can be quite unnerving. Their patterns
of movement can be sketchy, unpredictable and Brownianly
random.

Some riders are able to pull-off stealth riding (and
I honestly declare I'm not one of them.)
There's a whole bunch of others who /think/ they are.

I don't want to see any more Law Enforcement pogroms
against cyclists. We've had enough of that here in
Vancouver already.

For some reason, fellow cyclists are our own worst
enemies, with some wanting to sic The Law on those
who don't toe the line, or don't conform to certain
notions of "appropriate" behaviour.

I wish we cyclists would stop tearing ourselves apart,
and instead apply that energy toward supporting each
other in a positive, inclusive and welcoming manner.

Wouldn't that be nice?


cheers,
Tom
--
Nothing is safe from me.
I'm really at:
tkeats curlicue vcn dot bc dot ca
SMS
2008-11-24 05:06:33 UTC
Permalink
Post by j***@stanfordalumni.org
My laser pointer is less than 1W but is greatly blinding. Why aim a
light at the face of oncoming people unless it is a gesture of self
righteous pride. I met a guy on the Dumbarton bridge yesterday with
two of those lights aimed right in my face. He used your excuse about
how few watts they emitted.
Well it really was not aimed at anyone's face. It was already angled
down slightly, but I angled it down more after she complained. It may
have been blinding her because she had been riding in the pitch black
until I came along.
Post by j***@stanfordalumni.org
Did you consider a citizens arrest of unlit pedestrians you met? Hell
They are even worse because they have no metal reflecting bicycle.
It is not against the law to be an unlit pedestrian, though it should be
when you're walking on the road or on mixed use paths.
Frank Krygowski
2008-11-24 15:54:31 UTC
Permalink
Post by SMS
My laser pointer is less than 1W but is greatly blinding.  Why aim a
light at the face of oncoming people unless it is a gesture of self
righteous pride.  I met a guy on the Dumbarton bridge yesterday with
two of those lights aimed right in my face.  He used your excuse about
how few watts they emitted.
Well it really was not aimed at anyone's face. It was already angled
down slightly, but I angled it down more after she complained. It may
have been blinding her because she had been riding in the pitch black
until I came along.
It was blinding her because it's a flashlight, not a proper
headlight.

Every proper headlight on every automobile, motorcycle, scooter, or
other road vehicle features optics designed to light the road but not
blind oncoming road users.

The units you've always espoused have never had proper, non-blinding
optics. Don't pretend you weren't told that 100 times.

- Frank Krygowski
j***@stanfordalumni.org
2008-11-24 16:22:27 UTC
Permalink
Post by Frank Krygowski
My laser pointer is less than 1W but is greatly blinding.  Why aim
a light at the face of oncoming people unless it is a gesture of
self righteous pride.  I met a guy on the Dumbarton bridge
yesterday with two of those lights aimed right in my face.  He
used your excuse about how few watts they emitted.
Well it really was not aimed at anyone's face. It was already
angled down slightly, but I angled it down more after she
complained. It may have been blinding her because she had been
riding in the pitch black until I came along.
It was blinding her because it's a flashlight, not a proper
headlight.
Every proper headlight on every automobile, motorcycle, scooter, or
other road vehicle features optics designed to light the road but
not blind oncoming road users.
That may be theoretically so but HID headlights on cars are blinding
just the same and seem to operate on the assumption that roads are
level and smooth, because with slightest irregularities the lights
strike oncoming drivers right in the face, just like the bicycle
lights.
Post by Frank Krygowski
The units you've always espoused have never had proper, non-blinding
optics. Don't pretend you weren't told that 100 times.
I sense that people with these lights are so proud of them because
they have them on in daylight, aimed into oncoming traffic at eye
level. Even in daylight the effect is annoying. My first reaction is
to wish I had my laser pointer at hand.

Here is what they advertise with blinding brightness. Watch that
light:

http://www.xenonpros.com/?gclid=CMuAj7OcjpcCFQ89awod2C1DGA

Jobst Brandt
SMS
2008-11-24 16:37:46 UTC
Permalink
Post by j***@stanfordalumni.org
That may be theoretically so but HID headlights on cars are blinding
just the same and seem to operate on the assumption that roads are
level and smooth, because with slightest irregularities the lights
strike oncoming drivers right in the face, just like the bicycle
lights.
The lights I find most annoying are those flashing LED bicycle lights
and HID bicycle headlights. OTOH, the former does make the cyclist
visible to motor vehicles in the daytime which is their goal, and the
latter does light the road sufficiently for high speed night riding.

I have a dynamo light on the bike I was riding in San Francisco on
Saturday night, and it was just a complete waste of perfectly good human
power to use it. Too weak to make it a good "being seen" light at the
speeds that were practical on those roads, and totally worthless as a
light to illuminate the road. As my wife said, at least people can hear
you approaching (it's a tire driven dynamo). Dynamo lights are
sufficient for low speed rides around town on familiar well-lit streets,
but on a pitch black and foggy road with hundreds of unlit bicyclists
that don't know where they're going you need something better.
j***@stanfordalumni.org
2008-11-24 17:08:33 UTC
Permalink
Post by SMS
Post by j***@stanfordalumni.org
That may be theoretically so but HID headlights on cars are
blinding just the same and seem to operate on the assumption that
roads are level and smooth, because with slightest irregularities
the lights strike oncoming drivers right in the face, just like the
bicycle lights.
The lights I find most annoying are those flashing LED bicycle
lights and HID bicycle headlights. OTOH, the former does make the
cyclist visible to motor vehicles in the daytime which is their
goal, and the latter does light the road sufficiently for high speed
night riding.
I have a dynamo light on the bike I was riding in San Francisco on
Saturday night, and it was just a complete waste of perfectly good
human power to use it. Too weak to make it a good "being seen"
light at the speeds that were practical on those roads, and totally
worthless as a light to illuminate the road. As my wife said, at
least people can hear you approaching (it's a tire driven dynamo).
Dynamo lights are sufficient for low speed rides around town on
familiar well-lit streets, but on a pitch black and foggy road with
hundreds of unlit bicyclists that don't know where they're going you
need something better.
As another thread states, Bicycling is too dangerous to be done by
reasonable people. At least that is what I gather from "Take the
lane" writers, helmet wars, and need for dark goggles and intense
front and rear lights. Besides, riding on anything other than carbon
fiber is also a hazard.

Bicycling has been infested by a conformity similar to that of autos
(aka trucks and SUV's).

Jobst Brandt
SMS
2008-11-24 17:20:07 UTC
Permalink
Post by j***@stanfordalumni.org
Bicycling has been infested by a conformity similar to that of autos
(aka trucks and SUV's).
There are still ample opportunities to not conform. Alas, the price of
non-conformity is often a lot higher now than in the past.

I owned an SUV before the term SUV was even coined (an old Toyota Land
Cruiser). I had to sell it once everyone had an SUV, or I would be
accused of being a conformist.
Tom Kunich
2008-11-24 17:59:32 UTC
Permalink
Post by SMS
There are still ample opportunities to not conform. Alas, the price of
non-conformity is often a lot higher now than in the past.
You mean that steel bikes are more expensive now?
Post by SMS
I owned an SUV before the term SUV was even coined (an old Toyota Land
Cruiser). I had to sell it once everyone had an SUV, or I would be accused
of being a conformist.
Why would anyone own a vehicle designed to look macho? That alone means that
you ain't.
Tom Sherman
2008-11-26 04:46:29 UTC
Permalink
Post by SMS
Post by j***@stanfordalumni.org
Bicycling has been infested by a conformity similar to that of autos
(aka trucks and SUV's).
There are still ample opportunities to not conform. Alas, the price of
non-conformity is often a lot higher now than in the past.
[...]
Recumbent bicycles are not that expensive!
Post by SMS
I owned an SUV before the term SUV was even coined (an old Toyota Land
Cruiser). I had to sell it once everyone had an SUV, or I would be
accused of being a conformist.
If it has manual door locks, crank windows, vinyl seats and a tractor
engine (1980's Land Cruiser station wagon) is it really a SUV?
--
Tom Sherman - 42.435731,-83.985007
If you are not a part of the solution, you are a part of the precipitate.
SMS
2008-11-25 05:28:51 UTC
Permalink
Post by Tom Sherman
If it has manual door locks, crank windows, vinyl seats and a tractor
engine (1980's Land Cruiser station wagon) is it really a SUV?
Cloth seats, crank windows, manual locks, and a Chevrolet straight-6
engine, manual locking hubs, and of course manual transmission.
Tom Sherman
2008-11-26 05:30:28 UTC
Permalink
Post by SMS
Post by Tom Sherman
If it has manual door locks, crank windows, vinyl seats and a tractor
engine (1980's Land Cruiser station wagon) is it really a SUV?
Cloth seats, crank windows, manual locks, and a Chevrolet straight-6
engine, manual locking hubs, and of course manual transmission.
And of course, a transfer case and manually locking hubs.
--
Tom Sherman - 42.435731,-83.985007
If you are not a part of the solution, you are a part of the precipitate.
SMS
2008-11-25 05:35:13 UTC
Permalink
Post by Tom Sherman
Post by SMS
Post by Tom Sherman
If it has manual door locks, crank windows, vinyl seats and a tractor
engine (1980's Land Cruiser station wagon) is it really a SUV?
Cloth seats, crank windows, manual locks, and a Chevrolet straight-6
engine, manual locking hubs, and of course manual transmission.
And of course, a transfer case and manually locking hubs.
Fix your computer's RTC Tom.
Tom Sherman
2008-11-25 06:13:58 UTC
Permalink
Post by SMS
Post by Tom Sherman
Post by SMS
Post by Tom Sherman
If it has manual door locks, crank windows, vinyl seats and a
tractor engine (1980's Land Cruiser station wagon) is it really a SUV?
Cloth seats, crank windows, manual locks, and a Chevrolet straight-6
engine, manual locking hubs, and of course manual transmission.
And of course, a transfer case and manually locking hubs.
Fix your computer's RTC Tom.
Hey, I am just so speedy that I am a day ahead. ;)

(I am using a new laptop that I picked up because it was on sale, in
stock and my desktop's power supply died and will likely not come back
from the repair shop for a couple of weeks). Two days in, and not a fan
of Vista.
--
Tom Sherman - 42.435731,-83.985007
If you are not a part of the solution, you are a part of the precipitate.
SMS
2008-11-25 16:33:32 UTC
Permalink
Post by Tom Sherman
Post by SMS
Post by Tom Sherman
If it has manual door locks, crank windows, vinyl seats and a tractor
engine (1980's Land Cruiser station wagon) is it really a SUV?
Cloth seats, crank windows, manual locks, and a Chevrolet straight-6
engine, manual locking hubs, and of course manual transmission.
And of course, a transfer case and manually locking hubs.
I never got the PTO wench <sic>. I wonder if the new models even still
have that capability.
Tom Sherman
2008-11-26 04:54:27 UTC
Permalink
Post by SMS
Post by Tom Sherman
Post by SMS
Post by Tom Sherman
If it has manual door locks, crank windows, vinyl seats and a
tractor engine (1980's Land Cruiser station wagon) is it really a SUV?
Cloth seats, crank windows, manual locks, and a Chevrolet straight-6
engine, manual locking hubs, and of course manual transmission.
And of course, a transfer case and manually locking hubs.
I never got the PTO wench <sic>. I wonder if the new models even still
have that capability.
Land Rover dropped the PTO from it vehicles, so you can no longer use
one to run farm equipment. :(
--
Tom Sherman - 42.435731,-83.985007
If you are not a part of the solution, you are a part of the precipitate.
Dane Buson
2008-11-25 18:46:28 UTC
Permalink
Post by Tom Sherman
Post by SMS
Post by j***@stanfordalumni.org
Bicycling has been infested by a conformity similar to that of autos
(aka trucks and SUV's).
There are still ample opportunities to not conform. Alas, the price of
non-conformity is often a lot higher now than in the past.
[...]
Recumbent bicycles are not that expensive!
Now Tom, I thought we agreed we weren't going to talk about those in
polite company?

/me looks around

Errrr, never mind, carry on.

Any recommendations for a tadpole trike? I'm getting tired of banging
my hips during icy winter days.
--
Dane Buson - ***@unixbigots.org
"...you might as well skip the Xmas celebration completely, and instead
sit in front of your linux computer playing with the
all-new-and-improved linux kernel version."
(By Linus Torvalds)
Tom Sherman
2008-11-26 05:01:23 UTC
Permalink
Post by Dane Buson
Post by Tom Sherman
Post by SMS
Post by j***@stanfordalumni.org
Bicycling has been infested by a conformity similar to that of autos
(aka trucks and SUV's).
There are still ample opportunities to not conform. Alas, the price of
non-conformity is often a lot higher now than in the past.
[...]
Recumbent bicycles are not that expensive!
Now Tom, I thought we agreed we weren't going to talk about those in
polite company?
/me looks around
Errrr, never mind, carry on.
Indeed! ;)
Post by Dane Buson
Any recommendations for a tadpole trike? I'm getting tired of banging
my hips during icy winter days.
USian made, and reasonably priced: <http://www.catrike.com/>.

High performance, good handling but still corrosion resistant:
<http://www.windcheetah.co.uk/>.

Rear suspension is nice, since it is hard to avoid potholes with all
three wheel tracks, and this one is also corrosion resistant:
<http://www.optima-cycles.nl/main/en/modellen/5.html?Itemid=27>.

Laugh at the cold rain: <http://leitra.dk/news.php>.
--
Tom Sherman - 42.435731,-83.985007
If you are not a part of the solution, you are a part of the precipitate.
Edward Dolan
2008-11-26 14:09:11 UTC
Permalink
"Tom Sherman" <***@yahoo.com> wrote in message news:ggil85$tfn$***@news.motzarella.org...
[...]
Post by Tom Sherman
USian made, and reasonably priced: <http://www.catrike.com/>.
Ugh! I go to the Catrike website and the first thing I see is a picture of
old Larry Varney linked to his review on BROL. Why hasn't that old Kentucky
coot croaked by now? Anyone who bases a decision on a review of his has got
to be nuts. Larry Varney couldn't think his way out of a paper bag. I see he
still has his Santa Claus beard. What an ugly freak he is!
Post by Tom Sherman
<http://www.windcheetah.co.uk/>.
You bet, just take all your money out of the bank and give it to these
assholes.
[...]

Regards,

Ed Dolan the Great - Minnesota
aka
Saint Edward the Great - Order of the Perpetual Sorrows - Minnesota
Dane Buson
2008-11-26 19:31:51 UTC
Permalink
Post by Tom Sherman
Post by Dane Buson
Post by Tom Sherman
Recumbent bicycles are not that expensive!
Now Tom, I thought we agreed we weren't going to talk about those in
polite company?
/me looks around
Errrr, never mind, carry on.
Indeed! ;)
Post by Dane Buson
Any recommendations for a tadpole trike? I'm getting tired of banging
my hips during icy winter days.
USian made, and reasonably priced: <http://www.catrike.com/>.
Possible, but since I'd only rarely be riding it, still too much cash.
Admittedly I knew that before I even asked the question. I guess it's
time to pick up some Atomic Zombie books.
Post by Tom Sherman
<http://www.windcheetah.co.uk/>.
Hmm, did I mention I want a trike, not to establish an annuity for their
grandchildren?
Post by Tom Sherman
Rear suspension is nice, since it is hard to avoid potholes with all
<http://www.optima-cycles.nl/main/en/modellen/5.html?Itemid=27>.
Laugh at the cold rain: <http://leitra.dk/news.php>.
Which should be nicely balanced by the people laughing at you. I'm fine
with a regular trike, but the enclosed ones turn the dork factor up to
11. Not to mention I cross multiple bridges with *high* winds at times.
--
Dane Buson - ***@unixbigots.org
Anyone who cannot cope with mathematics is not fully human. At best he
is a tolerable subhuman who has learned to wear shoes, bathe and not
make messes in the house.
-- Lazarus Long, "Time Enough for Love"
Dane Buson
2008-11-25 18:44:07 UTC
Permalink
Post by SMS
Post by j***@stanfordalumni.org
Bicycling has been infested by a conformity similar to that of autos
(aka trucks and SUV's).
There are still ample opportunities to not conform. Alas, the price of
non-conformity is often a lot higher now than in the past.
Pffft. Only if you want packaged conformity. Yes, a high zoot
Rivendell will set you back lots of dough and give you that
pseudo-retrogrouch credibility. On the other hand, $20 at a thrift store
will get you a slightly better than BSO that you can trick out for
minimal cash into a rideable differentiable bike. Sit-up-and-beg is the
new newsboy is the new fixed gear is the new black.
Post by SMS
I owned an SUV before the term SUV was even coined (an old Toyota Land
Cruiser). I had to sell it once everyone had an SUV, or I would be
accused of being a conformist.
Meh, who cares what the Jones think. Selling it to not look like a
conformist is being a fashionista just as much as buying it to be a
conformist.
--
Dane Buson - ***@unixbigots.org
The two most common things in the Universe are hydrogen and stupidity.
-- Harlan Ellison
j***@stanfordalumni.org
2008-11-25 23:26:27 UTC
Permalink
Post by Dane Buson
Post by SMS
Post by j***@stanfordalumni.org
Bicycling has been infested by a conformity similar to that of
autos (aka trucks and SUV's).
There are still ample opportunities to not conform. Alas, the price
of non-conformity is often a lot higher now than in the past.
Pffft. Only if you want packaged conformity. Yes, a high zoot
Rivendell will set you back lots of dough and give you that
pseudo-retrogrouch credibility. On the other hand, $20 at a thrift
store will get you a slightly better than BSO that you can trick out
for minimal cash into a rideable differentiable bike.
Sit-up-and-beg is the new newsboy is the new fixed gear is the new
black.
Post by SMS
I owned an SUV before the term SUV was even coined (an old Toyota
Land Cruiser). I had to sell it once everyone had an SUV, or I
would be accused of being a conformist.
Meh, who cares what the Jones think. Selling it to not look like a
conformist is being a fashionista just as much as buying it to be a
conformist.
Conformist or fashionista all fits in the same bag in that both are
concerned with perceived public image boosing instead of substance.
That may not resonate with many folks these days when not seeking
public acclaim is no longer acceptable. Adults are playing grade
school games at great expense financially and mentally.

Jobst Brandt
SMS
2008-11-25 23:38:40 UTC
Permalink
Post by Dane Buson
Post by SMS
I owned an SUV before the term SUV was even coined (an old Toyota Land
Cruiser). I had to sell it once everyone had an SUV, or I would be
accused of being a conformist.
Meh, who cares what the Jones think. Selling it to not look like a
conformist is being a fashionista just as much as buying it to be a
conformist.
Feh, that was a joke. I did sell it eventually because a vehicle that
got 11 city/13 highway, was impractical.
j***@stanfordalumni.org
2008-11-26 00:34:34 UTC
Permalink
Post by SMS
Post by Dane Buson
Post by SMS
I owned an SUV before the term SUV was even coined (an old Toyota
Land Cruiser). I had to sell it once everyone had an SUV, or I
would be accused of being a conformist.
Meh, who cares what the Jones think. Selling it to not look like a
conformist is being a fashionista just as much as buying it to be a
conformist.
Feh, that was a joke. I did sell it eventually because a vehicle that
got 11 city/13 highway, was impractical.
So when did it start getting poor gas mileage and if that wasn't a
change, why did you gt it in the first place if it wasn't to cloak
yourself in truck driver ambience, the bulldog on the block? You
probably sold it because you noticed that these vehicles must be
glossy black and have dark windows, something that hadn't become
fashionista at the time yet.

I watched a few local "truckers" get rid of their light colored rides
switching to black SUV's when they sensed the trend.

Jobst Brandt
SMS
2008-11-26 01:34:54 UTC
Permalink
Post by j***@stanfordalumni.org
Post by SMS
Post by Dane Buson
Post by SMS
I owned an SUV before the term SUV was even coined (an old Toyota
Land Cruiser). I had to sell it once everyone had an SUV, or I
would be accused of being a conformist.
Meh, who cares what the Jones think. Selling it to not look like a
conformist is being a fashionista just as much as buying it to be a
conformist.
Feh, that was a joke. I did sell it eventually because a vehicle that
got 11 city/13 highway, was impractical.
So when did it start getting poor gas mileage and if that wasn't a
change, why did you gt it in the first place if it wasn't to cloak
yourself in truck driver ambience, the bulldog on the block?
That was the rated mileage. I bought it as a second car to be able to
take 5 people and gear cross country skiing. In 16 years, I put less
than 80K miles on it. Between the poor mileage and an excessive mount of
repairs, and no longer going on the types of trips where I needed such a
vehicle, when someone approached me and wanted to buy it, I got rid of
it. It was the most un-SUV like 4WD vehicle around, no power anything,
all manual, and an engine designed for high torque, not for highway driving.
Tom Kunich
2008-11-24 17:57:48 UTC
Permalink
Besides, riding on anything other than carbon fiber is also a hazard.
In another three months I should be fully recovered from riding on carbon
fiber. My accident was last June.
Helmut Springer
2008-11-24 18:01:57 UTC
Permalink
Post by SMS
The lights I find most annoying are those flashing LED bicycle
lights and HID bicycle headlights. OTOH, the former does make the
cyclist visible to motor vehicles in the daytime which is their
goal,
A flashing LED in bright daylight? Good one 8)
Post by SMS
I have a dynamo light on the bike I was riding in San Francisco on
Saturday night, and it was just a complete waste of perfectly good
human power to use it.
You could install a reasonable one if it wasn't against your deepest
believe 8)
--
MfG/Best regards
helmut springer panta rhei
SMS
2008-11-24 18:07:53 UTC
Permalink
Post by Helmut Springer
Post by SMS
The lights I find most annoying are those flashing LED bicycle
lights and HID bicycle headlights. OTOH, the former does make the
cyclist visible to motor vehicles in the daytime which is their
goal,
A flashing LED in bright daylight? Good one 8)
Obviously you've never seen one of the Cree 3W LED flashing lights. They
are extremely bright and visible in the daytime.
Post by Helmut Springer
You could install a reasonable one if it wasn't against your deepest
believe 8)
I've seen people with the so-called "decent" ones. They are not much
better than the Union/Marwi. There is one supposedly really good one
from SolidLights (it's gotten good reviews from dynamo light users) but
it's like $300 just for the lamp.
Tom Sherman
2008-11-26 04:50:43 UTC
Permalink
Post by SMS
Post by Helmut Springer
Post by SMS
The lights I find most annoying are those flashing LED bicycle
lights and HID bicycle headlights. OTOH, the former does make the
cyclist visible to motor vehicles in the daytime which is their
goal,
A flashing LED in bright daylight? Good one 8)
Obviously you've never seen one of the Cree 3W LED flashing lights. They
are extremely bright and visible in the daytime.
Post by Helmut Springer
You could install a reasonable one if it wasn't against your deepest
believe 8)
I've seen people with the so-called "decent" ones. They are not much
better than the Union/Marwi. There is one supposedly really good one
from SolidLights (it's gotten good reviews from dynamo light users) but
it's like $300 just for the lamp.
Could not a Cree 3W LED be driven by a 3W dynamo hub, or two 3W Crees by
a 6W dynamo hub? Batteries do not cut it for certain people, such as
those who like long night rides to avoid the worst of the summer heat.
--
Tom Sherman - 42.435731,-83.985007
If you are not a part of the solution, you are a part of the precipitate.
SMS
2008-11-25 05:34:13 UTC
Permalink
Post by Tom Sherman
Could not a Cree 3W LED be driven by a 3W dynamo hub, or two 3W Crees by
a 6W dynamo hub? Batteries do not cut it for certain people, such as
those who like long night rides to avoid the worst of the summer heat.
Yes. Probably you could drive two 3W LEDs from a 3W hub if you were
going fast enough. The best option would be a hybrid system where the
dynamo charged a battery so you didn't waste excess generated power when
going fast, and could be at full brightness when slowing down. It would
also be good to have multiple brightness levels so you could select one
based on your needs.
Dane Buson
2008-11-25 19:14:32 UTC
Permalink
Post by SMS
Post by Tom Sherman
Could not a Cree 3W LED be driven by a 3W dynamo hub, or two 3W Crees by
a 6W dynamo hub? Batteries do not cut it for certain people, such as
those who like long night rides to avoid the worst of the summer heat.
Yes. Probably you could drive two 3W LEDs from a 3W hub if you were
going fast enough. The best option would be a hybrid system where the
dynamo charged a battery so you didn't waste excess generated power when
going fast, and could be at full brightness when slowing down. It would
also be good to have multiple brightness levels so you could select one
based on your needs.
It sounds like rather too much frippery (the battery anyway). It would
add expense weight and energy loss for very little real return. The
multiple brightness levels would be nice admittedly.
--
Dane Buson - ***@unixbigots.org
The mosquito is the state bird of New Jersey.
-- Andy Warhol
SMS
2008-11-25 19:53:46 UTC
Permalink
Post by Dane Buson
It sounds like rather too much frippery (the battery anyway). It would
add expense weight and energy loss for very little real return.
On the good dynamo powered LED lights, with switching regulators, you
already have the loss (technically there's no such thing as energy loss,
you're just converting more of the energy to heat through the
regulator). What's happening is that when you're going fast, rather than
burning out the LED due to too high a voltage, is that you're just
wasting that power. You have the same issue with over-voltage protected
incandescent dynamo lamps.
Post by Dane Buson
The
multiple brightness levels would be nice admittedly.
Yes, and the levels would not be based on the speed of the bicycle. You
could also choose to charge the batteries in the daytime from the
dynamo, with lights off, and if you really wanted to get fancy, only
engage the charger during downhill runs, where the drag wouldn't matter.
Dane Buson
2008-11-26 20:52:45 UTC
Permalink
Post by SMS
Post by Dane Buson
It sounds like rather too much frippery (the battery anyway). It would
add expense weight and energy loss for very little real return.
On the good dynamo powered LED lights, with switching regulators, you
already have the loss (technically there's no such thing as energy loss,
you're just converting more of the energy to heat through the
regulator).
Eh, with the battery you're getting double conversion losses (charging
in and taking out), plus leakage when it's not being used. In addition
the expense of replacing the battery when it dies, which is part of the
whole point of a dynamo setup is not worrying about that sort of thing.

You'd have to setup some sort of matrix and figure out the cost/benefit,
but I suspect it's not as good as you'd think.
Post by SMS
What's happening is that when you're going fast, rather than
burning out the LED due to too high a voltage, is that you're just
wasting that power. You have the same issue with over-voltage protected
incandescent dynamo lamps.
Eh, if after my 6 watts of LEDs are saturated they give off 2 watts of
heat, I don't really care. This is about having usable always available
lighting, this is not a min/maxing D&D session.
Post by SMS
Post by Dane Buson
The multiple brightness levels would be nice admittedly.
Yes, and the levels would not be based on the speed of the bicycle.
No actually that part is great. My problem is when I'm on bike paths
versus roads and don't want to blind other cyclists. I've never had any
problems because my light is dimmer when I'm slower, brighter when I'm
faster.
Post by SMS
You could also choose to charge the batteries in the daytime from the
dynamo, with lights off, and if you really wanted to get fancy, only
engage the charger during downhill runs, where the drag wouldn't matter.
Your solution is way too complicated (and yes that is a valid
engineering critique). KISS - You're adding cost and points of failure
for dubious to neglible benefit.
--
Dane Buson - ***@unixbigots.org
"I don't have to take this abuse from you -- I've got hundreds of
people waiting to abuse me."
-- Bill Murray, "Ghostbusters"
Peter Cole
2008-11-26 15:18:04 UTC
Permalink
Post by SMS
Post by Tom Sherman
Could not a Cree 3W LED be driven by a 3W dynamo hub, or two 3W Crees
by a 6W dynamo hub? Batteries do not cut it for certain people, such
as those who like long night rides to avoid the worst of the summer heat.
Yes. Probably you could drive two 3W LEDs from a 3W hub if you were
going fast enough. The best option would be a hybrid system where the
dynamo charged a battery so you didn't waste excess generated power when
going fast, and could be at full brightness when slowing down. It would
also be good to have multiple brightness levels so you could select one
based on your needs.
All you need to do is to design you light so that peak dynamo power
doesn't exceed LED power rating. The simple way is to just over-spec the
LED a bit (or use multiples). I can't see why you wouldn't want more
light the faster you're going. At low power/speed the LED wins because
the color stays constant and the efficiency only improves. Batteries are
less necessary with an LED head than an incandescent one. LED's are a
prefect match to a dynamo source without any other complexity.
Helmut Springer
2008-11-25 09:24:02 UTC
Permalink
Post by Tom Sherman
Could not a Cree 3W LED be driven by a 3W dynamo hub,
Sure.
Post by Tom Sherman
or two 3W Crees by a 6W dynamo hub?
The hub generator isn't limited to 3W: it is limited to roughly
500mA which translates to 3W with the German standard consumers.
Per construction the dynamo is more or less a stable current
provider and will happily deliver 500mA and 6W with the respective
consumers and sufficient speed. Which for modern LED lights isn't
that fast, 15-20km/h. This has been discusses in rather detail in
r.b.t before.
--
MfG/Best regards
helmut springer panta rhei
SMS
2008-11-25 14:10:15 UTC
Permalink
Post by Helmut Springer
Post by Tom Sherman
Could not a Cree 3W LED be driven by a 3W dynamo hub,
Sure.
Post by Tom Sherman
or two 3W Crees by a 6W dynamo hub?
The hub generator isn't limited to 3W: it is limited to roughly
500mA which translates to 3W with the German standard consumers.
Per construction the dynamo is more or less a stable current
provider and will happily deliver 500mA and 6W with the respective
consumers and sufficient speed. Which for modern LED lights isn't
that fast, 15-20km/h. This has been discusses in rather detail in
r.b.t before.
Yes, it's like a constant current source, but variable voltage. This is
a blessing and a curse. The incandescent lamps need to have voltage
regulators, typically a zener diode, so they don't burn out at high
speeds from over-voltage, which wastes power. Putting two in series is
one way to avoid wasting power at higher speeds.

An LED lamp, with a switching regulator could be designed to also charge
a battery at higher speeds, rather than just waste the excess power as
heat to be dissipated through a heat sink, but that's more complexity,
and more weight to carry around.
Frank Krygowski
2008-11-25 17:40:06 UTC
Permalink
Post by SMS
Post by Helmut Springer
Post by Tom Sherman
Could not a Cree 3W LED be driven by a 3W dynamo hub,
Sure.
Post by Tom Sherman
or two 3W Crees by a 6W dynamo hub?
The hub generator isn't limited to 3W: it is limited to roughly
500mA which translates to 3W with the German standard consumers.
Per construction the dynamo is more or less a stable current
provider and will happily deliver 500mA and 6W with the respective
consumers and sufficient speed.  Which for modern LED lights isn't
that fast, 15-20km/h.  This has been discusses in rather detail in
r.b.t before.
Yes, it's like a constant current source, but variable voltage. This is
a blessing and a curse. The incandescent lamps need to have voltage
regulators, typically a zener diode, so they don't burn out at high
speeds from over-voltage, which wastes power. Putting two in series is
one way to avoid wasting power at higher speeds.
An LED lamp, with a switching regulator could be designed to also charge
a battery at higher speeds, rather than just waste the excess power as
heat to be dissipated through a heat sink, but that's more complexity,
and more weight to carry around.
Since bike generators are typically output a constant 0.5 amps, and
since LEDs require regulated current, why does an LED headlight
require a switching regulator?

- Frank Krygowski
DennisTheBald
2008-11-25 23:54:33 UTC
Permalink
Post by Tom Sherman
Post by SMS
Post by Helmut Springer
Post by SMS
The lights I find most annoying are those flashing LED bicycle
lights and HID bicycle headlights. OTOH, the former does make the
cyclist visible to motor vehicles in the daytime which is their
goal,
A flashing LED in bright daylight? Good one 8)
Obviously you've never seen one of the Cree 3W LED flashing lights. They
are extremely bright and visible in the daytime.
Post by Helmut Springer
You could install a reasonable one if it wasn't against your deepest
believe 8)
I've seen people with the so-called "decent" ones. They are not much
better than the Union/Marwi. There is one supposedly really good one
from SolidLights (it's gotten good reviews from dynamo light users) but
it's like $300 just for the lamp.
Could not a Cree 3W LED be driven by a 3W dynamo hub, or two 3W Crees by
a 6W dynamo hub? Batteries do not cut it for certain people, such as
those who like long night rides to avoid the worst of the summer heat.
--
Tom Sherman - 42.435731,-83.985007
If you are not a part of the solution, you are a part of the precipitate.
You're still gonna need some batteries for this set up, small ones and
you're gonna want them so that you've got "stand light" anyway. But
you could surely keep ni-cad batteries charged from the dynohub and
roll merrily along. I think there maybe a better lens, or a more task
specific lens, than what comes on those flashlights. Still those
general purpose 3W flashlights do light up the road better than most
of stuff you can buy in a bike shop for less than $100 - but not as
good as what you can get for under a $100 and the autoparts store.
Frank Krygowski
2008-11-25 17:32:51 UTC
Permalink
Post by SMS
Post by SMS
The lights I find most annoying are those flashing LED bicycle
lights and HID bicycle headlights. OTOH, the former does make the
cyclist visible to motor vehicles in the daytime which is their
goal,
A flashing LED in bright daylight?  Good one   8)
Obviously you've never seen one of the Cree 3W LED flashing lights. They
are extremely bright and visible in the daytime.
And completely unnecessary in the daytime.
Post by SMS
You could install a reasonable one if it wasn't against your deepest
believe   8)
I've seen people with the so-called "decent" ones. They are not much
better than the Union/Marwi.
<sigh> I don't know what you've seen. Keep in mind that generator
powered halogen headlights are extremely popular in the multi-hundred-
mile, all-day-and-all-night Paris-Brest-Paris event. The only survey
I've seen of P-B-P riders claimed that the generator users were more
satisfied with their lights than the battery users.

Obviously, your impression of bike generators is stuck in the 1960s.
Post by SMS
There is one supposedly really good one
from SolidLights (it's gotten good reviews from dynamo light users) but
it's like $300 just for the lamp.
There are battery lamps and there are a few new generator lamps that
are in that price range. Similarly, there are wheelsets that sell for
thousands of dollars, and handlebars that sell for hundreds.

The existence of astronomically priced components does not mean that
perfectly ordinary ones are inadequate.

- Frank Krygowski
Dane Buson
2008-11-25 19:12:07 UTC
Permalink
Post by SMS
Post by Helmut Springer
You could install a reasonable one if it wasn't against your deepest
believe 8)
I've seen people with the so-called "decent" ones. They are not much
better than the Union/Marwi. There is one supposedly really good one
from SolidLights (it's gotten good reviews from dynamo light users) but
it's like $300 just for the lamp.
It's down to about $210 with the better exchange rate these days. Let's
see, some quick calculation. 150 GBP * 0.83 (removing VAT - make sure
to tell them to do this) + 5 GBP shipping = 129.5 * 1.54361 = $199.90.
Let's call it $200 with shipping and everything. Not too bad really.

I think mine was about $250 all told, since I bought it back when the
American Peso was a little weaker, but not trading at 2:1.

Going a little more downmarket, there's the Busch & Muller Lumotec Cyo
60 Senso N+ Switchable LED which is about $80 before removing VAT etc.,
so that would probably be a touch above $100 for a very nice light.

Also, with the better exchange rate, the very nice 2.4 W Busch & Muller
Topal LED Dynamo Headlamp is only $52.

http://www.sjscycles.co.uk/product.asp?pf_id=12041&src=froogleUS&currency=USDa

Really, there's no excuse to kvetch about inadequate dynamo lights
anymore. Not if you do even a smidge of research.
--
Dane Buson - ***@unixbigots.org
Three o'clock in the afternoon is always just a little too late or a little
too early for anything you want to do.
-- Jean-Paul Sartre
SMS
2008-11-25 19:41:56 UTC
Permalink
Post by Dane Buson
Also, with the better exchange rate, the very nice 2.4 W Busch & Muller
Topal LED Dynamo Headlamp is only $52.
http://www.sjscycles.co.uk/product.asp?pf_id=12041&src=froogleUS&currency=USDa
OMG, so someone did do an LED front light with no regulator circuitry,
"Busch & Muller Topal LED Dynamo Headlamp 2.4W for hub dynamo (requires
back light to be used).

Uh, so let's see how long that LED lasts going down a hill at 40MPH. Of
course you'd never do such a foolish thing with a 2.4W headlamp like
that, so it's self-limiting. And what if your rear light burns out or
becomes disconnected?

The IQ Cyo senso plus states that 7.5 V must not be exceeded, so watch
out there as well.
Frank Krygowski
2008-11-25 21:31:06 UTC
Permalink
Post by SMS
Post by Dane Buson
Also, with the better exchange rate, the very nice 2.4 W Busch & Muller
Topal LED Dynamo Headlamp is only $52.
http://www.sjscycles.co.uk/product.asp?pf_id=12041&src=froogleUS&curr...
OMG, so someone did do an LED front light with no regulator circuitry,
"Busch & Muller Topal LED Dynamo Headlamp 2.4W for hub dynamo (requires
back light to be used).
Uh, so let's see how long that LED lasts going down a hill at 40MPH.
You mean, when the generator is putting out 0.5 amp at 40 mph...

... as opposed to when the generator is putting out 0.5 amp at 15
mph? Hmm.

Study http://www.m-gineering.nl/son12vg.htm and meditate on "constant
current."

- Frank Krygowski
Tom Keats
2008-11-27 04:19:32 UTC
Permalink
Post by Frank Krygowski
Post by SMS
Post by Dane Buson
Also, with the better exchange rate, the very nice 2.4 W Busch & Muller
Topal LED Dynamo Headlamp is only $52.
http://www.sjscycles.co.uk/product.asp?pf_id=12041&src=froogleUS&curr...
OMG, so someone did do an LED front light with no regulator circuitry,
"Busch & Muller Topal LED Dynamo Headlamp 2.4W for hub dynamo (requires
back light to be used).
Uh, so let's see how long that LED lasts going down a hill at 40MPH.
You mean, when the generator is putting out 0.5 amp at 40 mph...
... as opposed to when the generator is putting out 0.5 amp at 15
mph? Hmm.
Study http://www.m-gineering.nl/son12vg.htm and meditate on "constant
current."
I'm not so sure I'd want to bomb down a hill at 40 MPH in
nighttime conditions with /any/ sort of lighting system.


cheers,
Tom
--
Nothing is safe from me.
I'm really at:
tkeats curlicue vcn dot bc dot ca
Dane Buson
2008-11-26 20:56:24 UTC
Permalink
Post by SMS
Post by Dane Buson
Also, with the better exchange rate, the very nice 2.4 W Busch & Muller
Topal LED Dynamo Headlamp is only $52.
http://www.sjscycles.co.uk/product.asp?pf_id=12041&src=froogleUS&currency=USDa
OMG, so someone did do an LED front light with no regulator circuitry,
"Busch & Muller Topal LED Dynamo Headlamp 2.4W for hub dynamo (requires
back light to be used).
Eh, it doesn't say explicitly it has no regulator (it probably does). They are
just (typically German-like) mandating a particular configuration. All in all,
what do you want for $50?
Post by SMS
Uh, so let's see how long that LED lasts going down a hill at 40MPH. Of
course you'd never do such a foolish thing with a 2.4W headlamp like
that, so it's self-limiting. And what if your rear light burns out or
becomes disconnected?
2.4 watts of well focused LED? I've gone faster with less light. I'm
sure it's actually probably pretty good.
Post by SMS
The IQ Cyo senso plus states that 7.5 V must not be exceeded, so watch
out there as well.
Meh, again, it's probably just arse-covering. I'll look for reviews in
six months and see if it's the cat's pajamas, or a steaming pile.
--
Dane Buson - ***@unixbigots.org
"God is my co-pilot but we crashed in the mountains and I had to eat him."
- Zakath - As seen on /.
DennisTheBald
2008-11-25 23:22:38 UTC
Permalink
Post by SMS
Post by Helmut Springer
Post by SMS
The lights I find most annoying are those flashing LED bicycle
lights and HID bicycle headlights. OTOH, the former does make the
cyclist visible to motor vehicles in the daytime which is their
goal,
A flashing LED in bright daylight? Good one 8)
Obviously you've never seen one of the Cree 3W LED flashing lights. They
are extremely bright and visible in the daytime.
Post by Helmut Springer
You could install a reasonable one if it wasn't against your deepest
believe 8)
I've seen people with the so-called "decent" ones. They are not much
better than the Union/Marwi. There is one supposedly really good one
from SolidLights (it's gotten good reviews from dynamo light users) but
it's like $300 just for the lamp.
Yeah, but 3W is just about the volume of them dyno hubs... a funny
coincidence that this is the consumption of that flashlight yer so
fond of. I reckon a handy fellow could fix one of 'em up to a
fullwave bridge rectifier, a pair of nicads, the frontend of that
flashlight and never be in the dark again. Well, I think it would be
easier with a flashlight that had 4 AAcells, but that's just a detail
as they sell 'em with that same LED and 4 batteries. I guess you
could step it down from 6 to 3V without a lot of fuss if you're really
sold on that particular model. Heck, if ya got a thing for blinking
you might be able to make it two halfwave rectifiers and blink outta
both ends at once.

Me, I wouldn't dream of putting my butt out on the roadway with
anything less than the 36W halogen headlight that I'm also using as a
hand warmer.
Tom Kunich
2008-11-24 18:08:14 UTC
Permalink
Post by Helmut Springer
Post by SMS
I have a dynamo light on the bike I was riding in San Francisco on
Saturday night, and it was just a complete waste of perfectly good
human power to use it.
You could install a reasonable one if it wasn't against your deepest
believe 8)
I have never seen a European type under-the-bottom-bracket generator being
sold here Helmut.

The kind available here are the side-of-the-tire kind that are very
inefficient and scrub a lot.

And of course the in-hub generators are the best of all. But none that I've
seen generate sufficient power for a decent headlight that is effective at
anything other than a dim glow that is supposed to alert drivers not to run
you over.

I wonder if you could couple the hub generator with an LED headlight and get
a decent illumination for riding at, say, 25 kph on an unlit roadway.
Helmut Springer
2008-11-24 18:19:33 UTC
Permalink
Post by Tom Kunich
I have never seen a European type under-the-bottom-bracket
generator being sold here Helmut.
Those have decreased quite a lot here by now...in-hub generators
have pretty much taken over that market segment.
Post by Tom Kunich
I wonder if you could couple the hub generator with an LED
headlight and get a decent illumination for riding at, say, 25 kph
on an unlit roadway.
IMO yes: at that speed you can easily power 2 or 3 headlights with
3W LED if you wanted. With recent models like Schmidt's Edelux or
B&M's Cyo Sport it has become easier, and technology robably won't
stop there.

http://nabendynamo.de/produkte/ar_tabelle.html shows some pictures
of modern LED headlights on the German market, powered by a hub
generator ot 20km/h.
--
MfG/Best regards
helmut springer panta rhei
SMS
2008-11-24 18:56:05 UTC
Permalink
Post by Helmut Springer
Post by Tom Kunich
I have never seen a European type under-the-bottom-bracket
generator being sold here Helmut.
Those have decreased quite a lot here by now...in-hub generators
have pretty much taken over that market segment.
Can you even buy the bottom bracket dynamos anymore? I have an old Sanyo
that still works, but I haven't seen that type for sale anywhere in the
world for a long time.
Post by Helmut Springer
IMO yes: at that speed you can easily power 2 or 3 headlights with
3W LED if you wanted. With recent models like Schmidt's Edelux or
B&M's Cyo Sport it has become easier, and technology robably won't
stop there.
I doubt if you could three 3W LED headlights with a 3W dynamo. Two might
be do-able at high speeds. These LED headlights waste a lot of power as
heat, as well as wasting some in the drive circuitry and regulation
circuitry.

"Efficiency and LED lifetime mainly depend on its cooling. This is why
we placed the LED on a massive copper heat sink, which in turn conducts
the heat to the aluminum housing, and then to the outside air. At high
speed the good cooling allows for an increase of 20% luminous flux
compared to usual LED headligts, some of which can reach more than 100°
Celsius (210° F)."

Of course the other issue with the Edelux is that not many people are
going to spending $212 on just a headlight.
Helmut Springer
2008-11-24 19:09:02 UTC
Permalink
Post by SMS
Can you even buy the bottom bracket dynamos anymore?
Yes.
Post by SMS
I doubt if you could three 3W LED headlights with a 3W dynamo.
Several people in d.r.f do, as the hub generator isn't limited to 3W
at sufficient speed. But Andreas has explained that at length in
r.b.t.
--
MfG/Best regards
helmut springer panta rhei
Peter Cole
2008-11-26 14:12:04 UTC
Permalink
Post by SMS
Post by Helmut Springer
Post by Tom Kunich
I have never seen a European type under-the-bottom-bracket
generator being sold here Helmut.
Those have decreased quite a lot here by now...in-hub generators
have pretty much taken over that market segment.
Can you even buy the bottom bracket dynamos anymore? I have an old Sanyo
that still works, but I haven't seen that type for sale anywhere in the
world for a long time.
Post by Helmut Springer
IMO yes: at that speed you can easily power 2 or 3 headlights with
3W LED if you wanted. With recent models like Schmidt's Edelux or
B&M's Cyo Sport it has become easier, and technology robably won't
stop there.
I doubt if you could three 3W LED headlights with a 3W dynamo. Two might
be do-able at high speeds.
Sure you could. At ~$6/LED you'd just be spending more than you need to.
Power LED's are more efficient at less than full power.
Post by SMS
These LED headlights waste a lot of power as
heat, as well as wasting some in the drive circuitry and regulation
circuitry.
LED's waste less power as heat than incandescents (that's why you get
more lumens/watt). You don't need regulation driving LED's from a dynamo
(as several have demonstrated), they're a good match as is.
Post by SMS
"Efficiency and LED lifetime mainly depend on its cooling. This is why
we placed the LED on a massive copper heat sink, which in turn conducts
the heat to the aluminum housing, and then to the outside air. At high
speed the good cooling allows for an increase of 20% luminous flux
compared to usual LED headligts, some of which can reach more than 100°
Celsius (210° F)."
Aluminum is the standard heat sink material for power electronics,
copper is just a bit of hype. Heat sinking is nothing new. All you need
is an aluminum light housing, finned if necessary. Check out the LED
MR-16 lights.
Post by SMS
Of course the other issue with the Edelux is that not many people are
going to spending $212 on just a headlight.
This is $20-30 technology (currently), only the bike business gives it
such obscene markups.
unknown
2008-11-24 20:27:20 UTC
Permalink
Post by Tom Kunich
Post by Helmut Springer
Post by SMS
I have a dynamo light on the bike I was riding in San Francisco on
Saturday night, and it was just a complete waste of perfectly good
human power to use it.
You could install a reasonable one if it wasn't against your deepest
believe 8)
I have never seen a European type under-the-bottom-bracket generator being
sold here Helmut.
The kind available here are the side-of-the-tire kind that are very
inefficient and scrub a lot.
And of course the in-hub generators are the best of all. But none that I've
seen generate sufficient power for a decent headlight that is effective at
anything other than a dim glow that is supposed to alert drivers not to run
you over.
You haven't seen any modern ones then.
Post by Tom Kunich
I wonder if you could couple the hub generator with an LED headlight and get
a decent illumination for riding at, say, 25 kph on an unlit roadway.
Easily, and I can't think of any reason to do anything else.
When you are providing the power, you don't want to waste it on
inefficient lighting technologies like bits of hot wire.
LEDs give the best bang for your buck, with better lumen/watt than
even HID.
SMS
2008-11-24 20:45:51 UTC
Permalink
Post by unknown
You haven't seen any modern ones then.
Post by Tom Kunich
I wonder if you could couple the hub generator with an LED headlight and get
a decent illumination for riding at, say, 25 kph on an unlit roadway.
Easily, and I can't think of any reason to do anything else.
When you are providing the power, you don't want to waste it on
inefficient lighting technologies like bits of hot wire.
LEDs give the best bang for your buck, with better lumen/watt than
even HID.
HID are far more efficient in lumens/watt.

But yes, there's no hot wire on LEDs, instead there's a very hot
semiconductor junction, with all the cooling challenges of
semiconductors. There is even active cooling available for LED lamps
now, because passive convection cooling can't keep up. Alas, nothing is
free. It was interesting to read the literature on the Edelux,
especially the part about the cooling.

Still, a 3W hub generator could sufficiently power a single 3W LED
headlight at moderate speed. Now all that needs to happen is for some
company in China to come out with such a headlight for $20, and it'll
enable a new generation of bicycle dynamo lighting. Certainly $212 LED
headlights aren't going to have a huge market.

The problem is that LED headlights aren't just an LED in place of a
filament bulb. The LED headlights require a switching regulator, you
can't drive them directly from the dynamo. The Edelux literature
mentions "very low loss" in their switching regulator but they aren't
more specific than that. The firt thing they must be doing is running
the output of the dynamo through a full wave bridge rectifier, which has
a maximum efficiency (with perfect diodes that don't exist) of 81.2%.
Then they're running the output through a DC-DC switching regulator,
which also has losses. By the time they're done. they probably only have
70% of the power remaining.
Frank Krygowski
2008-11-25 17:50:19 UTC
Permalink
Post by SMS
The problem is that LED headlights aren't just an LED in place of a
filament bulb. The LED headlights require a switching regulator, you
can't drive them directly from the dynamo.
I'm seriously curious about this point.

Almost all bike generators output 0.5 amp AC current. They pump that
same current into any resistive load, within reason. That's what
allows putting two 3W halogen headlamps in series with certain
generators. The same 0.5 amps flows through both and lights them
both.

If the output is already regulated to 0.5 amps, and if LEDs require a
regulated current, why is a switching regulator needed? For an LED
driven by a battery, of course a limiting resistor or complicated
constant current circuit is needed. But it seems LED requirements
naturally match generator characteristics.

Online and in at least one magazine, I've seen circuits used by
experimenters to build their own LED headlights for generators.
Several simply ran the AC output through a bridge rectifier, then into
the LED. One person skipped that, and just used two opposing LEDs,
with each functioning during half the AC cycle.

I briefly bench tested the latter scheme. It seemed to work fine, but
mine was a very brief test.

Why do commercial LED lamps intended for generators need anything
more?

- Frank Krygowski
DennisTheBald
2008-11-26 00:03:08 UTC
Permalink
Post by Frank Krygowski
Post by SMS
The problem is that LED headlights aren't just an LED in place of a
filament bulb. The LED headlights require a switching regulator, you
can't drive them directly from the dynamo.
I'm seriously curious about this point.
Almost all bike generators output 0.5 amp AC current. They pump that
same current into any resistive load, within reason. That's what
allows putting two 3W halogen headlamps in series with certain
generators. The same 0.5 amps flows through both and lights them
both.
If the output is already regulated to 0.5 amps, and if LEDs require a
regulated current, why is a switching regulator needed? For an LED
driven by a battery, of course a limiting resistor or complicated
constant current circuit is needed. But it seems LED requirements
naturally match generator characteristics.
Online and in at least one magazine, I've seen circuits used by
experimenters to build their own LED headlights for generators.
Several simply ran the AC output through a bridge rectifier, then into
the LED. One person skipped that, and just used two opposing LEDs,
with each functioning during half the AC cycle.
I briefly bench tested the latter scheme. It seemed to work fine, but
mine was a very brief test.
Why do commercial LED lamps intended for generators need anything
more?
- Frank Krygowski
I'm with ya here. I want to know why the LEDs couldn't be the
rectifier. I guess if the voltage gets too high they turn into NEDs
(noise emitting diodes, albeit single use), but couldn't we limit that
with a battery instead of the more traditional resistor?
Frank Krygowski
2008-11-26 05:44:38 UTC
Permalink
Post by Frank Krygowski
Post by SMS
The problem is that LED headlights aren't just an LED in place of a
filament bulb. The LED headlights require a switching regulator, you
can't drive them directly from the dynamo.
I'm seriously curious about this point.
Almost all bike generators output 0.5 amp AC current.  They pump that
same current into any resistive load, within reason.  That's what
allows putting two 3W halogen headlamps in series with certain
generators.  The same 0.5 amps flows through both and lights them
both.
If the output is already regulated to 0.5 amps, and if LEDs require a
regulated current, why is a switching regulator needed?  For an LED
driven by a battery, of course a limiting resistor or complicated
constant current circuit is needed.  But it seems LED requirements
naturally match generator characteristics.
Online and in at least one magazine, I've seen circuits used by
experimenters to build their own LED headlights for generators.
Several simply ran the AC output through a bridge rectifier, then into
the LED.  One person skipped that, and just used two opposing LEDs,
with each functioning during half the AC cycle.
I briefly bench tested the latter scheme.  It seemed to work fine, but
mine was a very brief test.
Why do commercial LED lamps intended for generators need anything
more?
- Frank Krygowski
I'm with ya here.  I want to know why the LEDs couldn't be the
rectifier.  I guess if the voltage gets too high they turn into NEDs
(noise emitting diodes, albeit single use), but couldn't we limit that
with a battery instead of the more traditional resistor?
Looks to me like a fairly typical max reverse voltage is about 5
volts. If the two LEDs were in parallel, the forward one would dump
all the current at less than 5 volts.

If necessary, I suppose you could back them up with a standard diode
for more protection, but I'm not sure that's necessary.

I'm not an electrical engineer, but I wish a competent EE would
comment.

- Frank Krygowski
Peter Cole
2008-11-26 15:51:57 UTC
Permalink
Post by Frank Krygowski
Post by DennisTheBald
Post by Frank Krygowski
Post by SMS
The problem is that LED headlights aren't just an LED in place of a
filament bulb. The LED headlights require a switching regulator, you
can't drive them directly from the dynamo.
I'm seriously curious about this point.
Almost all bike generators output 0.5 amp AC current. They pump that
same current into any resistive load, within reason. That's what
allows putting two 3W halogen headlamps in series with certain
generators. The same 0.5 amps flows through both and lights them
both.
If the output is already regulated to 0.5 amps, and if LEDs require a
regulated current, why is a switching regulator needed? For an LED
driven by a battery, of course a limiting resistor or complicated
constant current circuit is needed. But it seems LED requirements
naturally match generator characteristics.
Online and in at least one magazine, I've seen circuits used by
experimenters to build their own LED headlights for generators.
Several simply ran the AC output through a bridge rectifier, then into
the LED. One person skipped that, and just used two opposing LEDs,
with each functioning during half the AC cycle.
I briefly bench tested the latter scheme. It seemed to work fine, but
mine was a very brief test.
Why do commercial LED lamps intended for generators need anything
more?
- Frank Krygowski
I'm with ya here. I want to know why the LEDs couldn't be the
rectifier. I guess if the voltage gets too high they turn into NEDs
(noise emitting diodes, albeit single use), but couldn't we limit that
with a battery instead of the more traditional resistor?
Looks to me like a fairly typical max reverse voltage is about 5
volts. If the two LEDs were in parallel, the forward one would dump
all the current at less than 5 volts.
If necessary, I suppose you could back them up with a standard diode
for more protection, but I'm not sure that's necessary.
I'm not an electrical engineer, but I wish a competent EE would
comment.
- Frank Krygowski
Some LED spec sheets caution to never reverse bias the devices, some
don't. It would probably work with many devices as you describe.
Peter Cole
2008-11-26 15:11:46 UTC
Permalink
Post by SMS
Post by unknown
You haven't seen any modern ones then.
Post by Tom Kunich
I wonder if you could couple the hub generator with an LED headlight
and get a decent illumination for riding at, say, 25 kph on an unlit
roadway.
Easily, and I can't think of any reason to do anything else.
When you are providing the power, you don't want to waste it on
inefficient lighting technologies like bits of hot wire.
LEDs give the best bang for your buck, with better lumen/watt than
even HID.
HID are far more efficient in lumens/watt.
Currently, it's roughly a tie. In actual products, HID's may still have
a slight edge, perhaps 50-60 l/W vs. 80-90 l/W, but at peak efficiency,
LED's are above 100 l/W. The problem with HID lamps is making them
small. You don't really need more than 150-300 lumen for bike use, which
translates to a HID lamp of 3-4W. You can't easily make them that small.
Post by SMS
But yes, there's no hot wire on LEDs, instead there's a very hot
semiconductor junction, with all the cooling challenges of
semiconductors. There is even active cooling available for LED lamps
now, because passive convection cooling can't keep up. Alas, nothing is
free. It was interesting to read the literature on the Edelux,
especially the part about the cooling.
Active cooling can make sense where space is limited, but passive
cooling a 3-5W thermal load is not very hard.
Post by SMS
Still, a 3W hub generator could sufficiently power a single 3W LED
headlight at moderate speed. Now all that needs to happen is for some
company in China to come out with such a headlight for $20, and it'll
enable a new generation of bicycle dynamo lighting. Certainly $212 LED
headlights aren't going to have a huge market.
The problem is that LED headlights aren't just an LED in place of a
filament bulb. The LED headlights require a switching regulator, you
can't drive them directly from the dynamo.
Sure you can.

The Edelux literature
Post by SMS
mentions "very low loss" in their switching regulator but they aren't
more specific than that. The firt thing they must be doing is running
the output of the dynamo through a full wave bridge rectifier, which has
a maximum efficiency (with perfect diodes that don't exist) of 81.2%.
Then they're running the output through a DC-DC switching regulator,
which also has losses. By the time they're done. they probably only have
70% of the power remaining.
Again, your efficiency figure for a FW bridge is wrong, but we've been
all over that.
DennisTheBald
2008-11-25 23:44:40 UTC
Permalink
On Nov 24, 2:27 pm, Phil W Lee <phil(at)lee-family(dot)me(dot)uk>
Post by unknown
Post by Tom Kunich
Post by Helmut Springer
Post by SMS
I have a dynamo light on the bike I was riding in San Francisco on
Saturday night, and it was just a complete waste of perfectly good
human power to use it.
You could install a reasonable one if it wasn't against your deepest
believe 8)
I have never seen a European type under-the-bottom-bracket generator being
sold here Helmut.
The kind available here are the side-of-the-tire kind that are very
inefficient and scrub a lot.
And of course the in-hub generators are the best of all. But none that I've
seen generate sufficient power for a decent headlight that is effective at
anything other than a dim glow that is supposed to alert drivers not to run
you over.
You haven't seen any modern ones then.
Post by Tom Kunich
I wonder if you could couple the hub generator with an LED headlight and get
a decent illumination for riding at, say, 25 kph on an unlit roadway.
Easily, and I can't think of any reason to do anything else.
When you are providing the power, you don't want to waste it on
inefficient lighting technologies like bits of hot wire.
LEDs give the best bang for your buck, with better lumen/watt than
even HID.
Best bang for yer buck? if yer talking lumen per watt then yes,
without a doubt...
But, a dozen 3W LED flashlights taped into an array isn't as effective
as one 36W halogen running light that would retail 2 fer $20 at almost
any auto parts store in the USofA. Granted the same 24 AA batteries
probably won't run that halogen lamp long enough (or at all in an
8x3 set up?-) and yer 12V deep cycle is gonna set you back another
$20-$30. And you're not gonna be able to charge it with two SON dyno
hubs. If you're talking about banging some actual greenbacks then
lead acid and halogen is your best bet. Even the Shimano dynohub
(which I hear is a cheap imitation of them European ones) will set you
back close to a hundred smackaroos.

Now if you've got a link to a vendor of say a 12W LED I'd love to see
it.
I mean I've seen some 5W in the catalog but not on the store shelves,
I would use these 3W flashlights in a pinch, they do throw some light
- way more than most of the POS toys that you can buy in a bike shop.
I carry one for a backup. But on my regular run it would have to be
just as a tail light or maybe taped to my head so that I could point
it at the moron's... er uh, motorist's windshields.
SMS
2008-11-26 01:28:34 UTC
Permalink
Post by DennisTheBald
If you're talking about banging some actual greenbacks then
lead acid and halogen is your best bet.
Nah, you don't need serious greenbacks for lead acid and halogen. In
fact, I don't think you can get much cheaper than a 12V lead acid gelled
electrolyte battery and a 12 volt halogen lamp for a good commute
system, when you're not all that concerned about weight, and don't want
to spend much money.

The battery is $10-22 depending on the capacity you want at
"http://tinyurl.com/5sn7fd" and they're not even the cheapest source.

A 12 volt halogen headlamp varies in price. MR16 lamps have an excellent
beam pattern for cycling applications. You can get a set of two for $23
at "http://tinyurl.com/5as6aw" but you should replace the lamp with
something lower wattage like a 10W or 20W lamp.

I've also used 14W and 25W PAR36 sealed beams. They have a flood beam
pattern, and the large reflector really helps efficiency. See
"http://tinyurl.com/5mp63u". For some reason the PAR36 beams seem to get
more respect from vehicles during commuting. They may think that a
motorcycle is approaching, rather than a bicycle. These lights are not
blinding like HID lights. I don't even use an enclosure, these are
lightweight all plastic beams, and I mount them directly to an
insulator, then to the bike (on a quill stem bike use a steel reflector
bracket).

You can get a set of 55W driving lamps for less than $10 at Harbor
Freight, but the lowest wattage H3 bulbs are 25W, and cost $11.50 each.

You can get a lead-acid charger for $5 on sale from Harbor Freight.
"http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=42292".

Add a fuse and some wire, and you've got a very good commute systems for
well under $50, depending on the lamps and batteries you choose. You
can also power a xenon strobe off the same battery, and it's much more
visible than all but the best LED rear flashers.

Google "Bicycle Lighting" and click on "I'm Feeling Lucky." You'll go
straight to an amazing web site with a lot of information on DIY bicycle
lighting. OMG, that's my site!
DennisTheBald
2008-11-26 20:46:14 UTC
Permalink
Post by SMS
Post by DennisTheBald
If you're talking about banging some actual greenbacks then
lead acid and halogen is your best bet.
Nah, you don't need serious greenbacks for lead acid and halogen. In
fact, I don't think you can get much cheaper than a 12V lead acid gelled
electrolyte battery and a 12 volt halogen lamp for a good commute
system, when you're not all that concerned about weight, and don't want
to spend much money.
The battery is $10-22 depending on the capacity you want at
"http://tinyurl.com/5sn7fd" and they're not even the cheapest source.
A 12 volt halogen headlamp varies in price. MR16 lamps have an excellent
beam pattern for cycling applications. You can get a set of two for $23
at "http://tinyurl.com/5as6aw" but you should replace the lamp with
something lower wattage like a 10W or 20W lamp.
I've also used 14W and 25W PAR36 sealed beams. They have a flood beam
pattern, and the large reflector really helps efficiency. See
"http://tinyurl.com/5mp63u". For some reason the PAR36 beams seem to get
more respect from vehicles during commuting. They may think that a
motorcycle is approaching, rather than a bicycle. These lights are not
blinding like HID lights. I don't even use an enclosure, these are
lightweight all plastic beams, and I mount them directly to an
insulator, then to the bike (on a quill stem bike use a steel reflector
bracket).
You can get a set of 55W driving lamps for less than $10 at Harbor
Freight, but the lowest wattage H3 bulbs are 25W, and cost $11.50 each.
You can get a lead-acid charger for $5 on sale from Harbor Freight.
"http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=42292".
Add a fuse and some wire, and you've got a very good commute systems for
well under $50, depending on the lamps and batteries you choose. You
can also power a xenon strobe off the same battery, and it's much more
visible than all but the best LED rear flashers.
Google "Bicycle Lighting" and click on "I'm Feeling Lucky." You'll go
straight to an amazing web site with a lot of information on DIY bicycle
lighting. OMG, that's my site!
yeah, that's what I'm saying, lumens per watt may be higher with LEDs,
but if the conversation is lumens per buck then lead acid/halogen is
the real deal. And you're a commuter, not some weight wennie
recreational racer... hauling around a 7-12amp hour gel cell ain't no
big deal to the pannier toting set.

I'm using 36W halogen bulbs, the difference in the amount of light
isn't that severe between them and regular 55W headlights, but my burn
time would be about 50% less with the same battery. I've been using
these things since way bay in the 90's when I rode a wedgie. But I do
have an enclosure - I bought a running lights kit, cost less that $20,
came with 36W bulbs, included a switch and a chunk of wire (of course
the instructions were grounding thru the body) and the lens does a
really good job of focusing the light where I want it.

I like a flashing zenon light too... the coast guard approved single D
cell number will slide down the rails of most wedgie saddles quite
nicely. I'd like to find a source of those zenon lights they mount on
the top of the school buses.

You can't touch this setup with stuff from the bike shop, even big
buck stuff. And this time of year, wrap yer rear rack with blinking
Christmas lights just to be festive, why not you've got plenty of
juice to spare.

I wouldn't rule out switching over to a hub generator / LED combo at
some point, like after I win the lottery or something.
SMS
2008-11-26 21:55:27 UTC
Permalink
Post by DennisTheBald
yeah, that's what I'm saying, lumens per watt may be higher with LEDs,
but if the conversation is lumens per buck then lead acid/halogen is
the real deal. And you're a commuter, not some weight wennie
recreational racer... hauling around a 7-12amp hour gel cell ain't no
big deal to the pannier toting set.
I used to use the 6.5AH or 7AH, but for a 1 hour commute with a 14W 12V
headlamp, a smaller battery is fine, i.e. a 2.2AH.
Post by DennisTheBald
I wouldn't rule out switching over to a hub generator / LED combo at
some point, like after I win the lottery or something.
Dynamo hubs are now being manufactured by more suppliers so costs will
come down, especially as part of complete bicycles. As after-market
add-ons they'll still be a lot due to the cost of a new wheel, as well
as mark-ups down the supply chain.
Helmut Springer
2008-11-27 08:17:43 UTC
Permalink
Post by SMS
Post by DennisTheBald
I wouldn't rule out switching over to a hub generator / LED combo
at some point, like after I win the lottery or something.
Dynamo hubs are now being manufactured by more suppliers so costs
will come down,
The cheapest Shimano goes at 24EUR retail here, even low cost
department store everyday bicycles tend to feature something like
that. Any everyday bicycle above 800EUR has one for sure, above
1000EUR you'll typically have a very decent Shimano and LEDs.
People like simple and carefree equipment...
--
MfG/Best regards
helmut springer panta rhei
Tom Sherman
2008-11-27 02:29:36 UTC
Permalink
Post by DennisTheBald
[...]
I'm using 36W halogen bulbs, the difference in the amount of light
isn't that severe between them and regular 55W headlights, but my burn
time would be about 50% less with the same battery. I've been using
these things since way bay in the 90's when I rode a wedgie. But I do
have an enclosure - I bought a running lights kit, cost less that $20,
came with 36W bulbs, included a switch and a chunk of wire (of course
the instructions were grounding thru the body) and the lens does a
really good job of focusing the light where I want it.
I like the idea of a 36W HID for my bicycle.
Post by DennisTheBald
I like a flashing zenon light too... the coast guard approved single D
cell number will slide down the rails of most wedgie saddles quite
nicely. I'd like to find a source of those zenon lights they mount on
the top of the school buses.
Top of a school bus? Take a portable ladder and battery powered angle
grinder with a cutting wheel. ;)
--
Tom Sherman - 42.435731,-83.985007
If you are not a part of the solution, you are a part of the precipitate.
unknown
2008-11-27 00:30:12 UTC
Permalink
Post by DennisTheBald
On Nov 24, 2:27 pm, Phil W Lee <phil(at)lee-family(dot)me(dot)uk>
Post by unknown
Post by Tom Kunich
Post by Helmut Springer
Post by SMS
I have a dynamo light on the bike I was riding in San Francisco on
Saturday night, and it was just a complete waste of perfectly good
human power to use it.
You could install a reasonable one if it wasn't against your deepest
believe 8)
I have never seen a European type under-the-bottom-bracket generator being
sold here Helmut.
The kind available here are the side-of-the-tire kind that are very
inefficient and scrub a lot.
And of course the in-hub generators are the best of all. But none that I've
seen generate sufficient power for a decent headlight that is effective at
anything other than a dim glow that is supposed to alert drivers not to run
you over.
You haven't seen any modern ones then.
Post by Tom Kunich
I wonder if you could couple the hub generator with an LED headlight and get
a decent illumination for riding at, say, 25 kph on an unlit roadway.
Easily, and I can't think of any reason to do anything else.
When you are providing the power, you don't want to waste it on
inefficient lighting technologies like bits of hot wire.
LEDs give the best bang for your buck, with better lumen/watt than
even HID.
Best bang for yer buck? if yer talking lumen per watt then yes,
without a doubt...
Yes, I was referring to the energy budget, not the financial one.
Peter Cole
2008-11-26 14:01:02 UTC
Permalink
Post by Tom Kunich
Post by Helmut Springer
Post by SMS
I have a dynamo light on the bike I was riding in San Francisco on
Saturday night, and it was just a complete waste of perfectly good
human power to use it.
You could install a reasonable one if it wasn't against your deepest
believe 8)
I have never seen a European type under-the-bottom-bracket generator
being sold here Helmut.
The kind available here are the side-of-the-tire kind that are very
inefficient and scrub a lot.
And of course the in-hub generators are the best of all. But none that
I've seen generate sufficient power for a decent headlight that is
effective at anything other than a dim glow that is supposed to alert
drivers not to run you over.
I wonder if you could couple the hub generator with an LED headlight and
get a decent illumination for riding at, say, 25 kph on an unlit roadway.
I've ridden all night side-by-side with riders using very good hub
dynamos and lights. They work pretty well, a bit better than a good 2.5W
halogen like my Cateye micro's, but not as good as a 10W system. I'd
rate them adequate for normal night riding, maybe not quite so under bad
conditions (lots of oncoming glare, rain, etc.).

A good LED head on a good dynamo should be a large improvement, in
absolute amount of light, efficiency, ruggedness, and eventually, cost.
But all that is pretty well known to dynamo users.
Frank Krygowski
2008-11-26 16:20:38 UTC
Permalink
Post by Peter Cole
I've ridden all night side-by-side with riders using very good hub
dynamos and lights. They work pretty well, a bit better than a good 2.5W
halogen like my Cateye micro's, but not as good as a 10W system.
It definitely depends on the system.

The incident that awakened me to the importance of optics was this:
My best friend decided to join me in night riding, so he shelled out
for a 10 watt system that was on sale somewhere. Sorry, I don't
remember the brand, but it was a typical moderately pricey system of
the day, with a small sealed lead-acid gel cell, wall-wart charger,
and headlamp. The generator I was using at the time was a Sanyo
bottom bracket unit, which I now know is a bit low on output power
(details on request). Anyway, we certainly expected his well-over-
$100 system to be greatly superior to my 2.4 watt headlight.

It wasn't even close. I'm sure his system threw out more lumens, but
the optics were so terrible that he couldn't ride more than about 8
mph in comfort. We could see dim light being scattered everywhere,
including way up into the trees; but there was no practical
illumination of the road. I believe he used that system only once or
twice, then left it on the bench until the battery eventually died.

Other 10 W halogen systems with better optics may be excellent; but I
don't know of one that actually has good road optics. Most are
designed for mountain biking.

- Frank Krygowski
DennisTheBald
2008-11-26 21:05:15 UTC
Permalink
Post by Frank Krygowski
Post by Peter Cole
I've ridden all night side-by-side with riders using very good hub
dynamos and lights. They work pretty well, a bit better than a good 2.5W
halogen like my Cateye micro's, but not as good as a 10W system.
It definitely depends on the system.
My best friend decided to join me in night riding, so he shelled out
for a 10 watt system that was on sale somewhere. Sorry, I don't
remember the brand, but it was a typical moderately pricey system of
the day, with a small sealed lead-acid gel cell, wall-wart charger,
and headlamp. The generator I was using at the time was a Sanyo
bottom bracket unit, which I now know is a bit low on output power
(details on request). Anyway, we certainly expected his well-over-
$100 system to be greatly superior to my 2.4 watt headlight.
It wasn't even close. I'm sure his system threw out more lumens, but
the optics were so terrible that he couldn't ride more than about 8
mph in comfort. We could see dim light being scattered everywhere,
including way up into the trees; but there was no practical
illumination of the road. I believe he used that system only once or
twice, then left it on the bench until the battery eventually died.
Other 10 W halogen systems with better optics may be excellent; but I
don't know of one that actually has good road optics. Most are
designed for mountain biking.
- Frank Krygowski
yeah, that's why you want to get the light kit from the autoparts
store, to get the lens that throws the light up the road instead of
into the ditch.
Peter Cole
2008-11-27 13:14:38 UTC
Permalink
Post by Frank Krygowski
Post by Peter Cole
I've ridden all night side-by-side with riders using very good hub
dynamos and lights. They work pretty well, a bit better than a good 2.5W
halogen like my Cateye micro's, but not as good as a 10W system.
It definitely depends on the system.
My best friend decided to join me in night riding, so he shelled out
for a 10 watt system that was on sale somewhere. Sorry, I don't
remember the brand, but it was a typical moderately pricey system of
the day, with a small sealed lead-acid gel cell, wall-wart charger,
and headlamp. The generator I was using at the time was a Sanyo
bottom bracket unit, which I now know is a bit low on output power
(details on request). Anyway, we certainly expected his well-over-
$100 system to be greatly superior to my 2.4 watt headlight.
It wasn't even close. I'm sure his system threw out more lumens, but
the optics were so terrible that he couldn't ride more than about 8
mph in comfort. We could see dim light being scattered everywhere,
including way up into the trees; but there was no practical
illumination of the road. I believe he used that system only once or
twice, then left it on the bench until the battery eventually died.
Other 10 W halogen systems with better optics may be excellent; but I
don't know of one that actually has good road optics. Most are
designed for mountain biking.
- Frank Krygowski
http://www.myra-simon.com/bike/schmidt.html

"Fourth was a VistaLite 500 lighting head with a 10W MR-11 bulb. This
was better than the Lumotec/Schmidt setup in all respects. The central
area was brighter, the dimmer area off to the sides was useful in seeing
what was going on at the sides of the road, and the beam was smoother
and whiter than my Lumotec/Schmidt setup. "
Frank Krygowski
2008-11-27 15:39:17 UTC
Permalink
Post by Peter Cole
Post by Frank Krygowski
Post by Peter Cole
I've ridden all night side-by-side with riders using very good hub
dynamos and lights. They work pretty well, a bit better than a good 2.5W
halogen like my Cateye micro's, but not as good as a 10W system.
It definitely depends on the system.
My best friend decided to join me in night riding, so he shelled out
for a 10 watt system that was on sale somewhere.  Sorry, I don't
remember the brand, but it was a typical moderately pricey system of
the day, with a small sealed lead-acid gel cell, wall-wart charger,
and headlamp.  The generator I was using at the time was a Sanyo
bottom bracket unit, which I now know is a bit low on output power
(details on request).  Anyway, we certainly expected his well-over-
$100 system to be greatly superior to my 2.4 watt headlight.
It wasn't even close.  I'm sure his system threw out more lumens, but
the optics were so terrible that he couldn't ride more than about 8
mph in comfort.  We could see dim light being scattered everywhere,
including way up into the trees; but there was no practical
illumination of the road.  I believe he used that system only once or
twice, then left it on the bench until the battery eventually died.
Other 10 W halogen systems with better optics may be excellent; but I
don't know of one that actually has good road optics.  Most are
designed for mountain biking.
- Frank Krygowski
http://www.myra-simon.com/bike/schmidt.html
"Fourth was a VistaLite 500 lighting head with a 10W MR-11 bulb. This
was better than the Lumotec/Schmidt setup in all respects. The central
area was brighter, the dimmer area off to the sides was useful in seeing
what was going on at the sides of the road, and the beam was smoother
and whiter than my Lumotec/Schmidt setup. "
When I say "good road optics" I include the ability to not blind
oncoming vehicle operators, and not to waste light in unproductive
directions.

All headlights truly designed for the road feature a cutoff to limit
upward waste and direct those lumens where they'll do some good.. No
MR-series bulb has that.

- Frank Krygowski
Peter Cole
2008-11-27 16:11:35 UTC
Permalink
Post by Frank Krygowski
Post by Peter Cole
http://www.myra-simon.com/bike/schmidt.html
"Fourth was a VistaLite 500 lighting head with a 10W MR-11 bulb. This
was better than the Lumotec/Schmidt setup in all respects. The central
area was brighter, the dimmer area off to the sides was useful in seeing
what was going on at the sides of the road, and the beam was smoother
and whiter than my Lumotec/Schmidt setup. "
When I say "good road optics" I include the ability to not blind
oncoming vehicle operators, and not to waste light in unproductive
directions.
All headlights truly designed for the road feature a cutoff to limit
upward waste and direct those lumens where they'll do some good.. No
MR-series bulb has that.
No, but I don't think anybody is designing new lights around MR
(multifaceted reflector) anymore. The reflector on those is designed to
diffuse the beam to avoid hot spots. LED's have much more compact
emitters, and even those that use a textured reflector diffuse the beam
much less.

I really think the only thing necessary to adapt a symmetrical beam like
those from a flashlight or MTB light is to just put a small hood on it.
Fresnel type lenses can shape the beam, but they tend to introduce
artifacts, too.
SMS
2008-11-27 16:47:29 UTC
Permalink
Post by Peter Cole
No, but I don't think anybody is designing new lights around MR
(multifaceted reflector) anymore. The reflector on those is designed to
diffuse the beam to avoid hot spots. LED's have much more compact
emitters, and even those that use a textured reflector diffuse the beam
much less.
MR lamps are still widely used in commercial battery powered lighting
systems. Note that while MR does stand for multifaceted reflector, there
are lamps that have smooth reflectors as well. It all depends on the
beam that you want to project.

One advantage of MR lamps is that you can have higher wattages because
of the way they dissipate the heat through the reflector. With LEDs (as
with many semiconductors) the thermodynamic challenges are very great as
the power increases. Just look at the white papers on dealing with high
power LED heat dissipation!
Post by Peter Cole
I really think the only thing necessary to adapt a symmetrical beam like
those from a flashlight or MTB light is to just put a small hood on it.
Fresnel type lenses can shape the beam, but they tend to introduce
artifacts, too.
Yeah, you could do this, but it really isn't necessary. Very little of
the light is "wasted" as it is.
Peter Cole
2008-11-28 05:23:49 UTC
Permalink
Post by SMS
Post by Peter Cole
No, but I don't think anybody is designing new lights around MR
(multifaceted reflector) anymore. The reflector on those is designed
to diffuse the beam to avoid hot spots. LED's have much more compact
emitters, and even those that use a textured reflector diffuse the
beam much less.
MR lamps are still widely used in commercial battery powered lighting
systems. Note that while MR does stand for multifaceted reflector, there
are lamps that have smooth reflectors as well. It all depends on the
beam that you want to project.
Out of 46 lights at Nashbar, only 1 seemed to be MR type, and I don't
think that's a new model.
Post by SMS
One advantage of MR lamps is that you can have higher wattages because
of the way they dissipate the heat through the reflector. With LEDs (as
with many semiconductors) the thermodynamic challenges are very great as
the power increases. Just look at the white papers on dealing with high
power LED heat dissipation!
Sub 10W power dissipation is trivial. All you need is a passive
heatsink. Cheap power transistors and diodes have been around for
decades, devices that handle much higher power levels.
Post by SMS
Post by Peter Cole
I really think the only thing necessary to adapt a symmetrical beam
like those from a flashlight or MTB light is to just put a small hood
on it. Fresnel type lenses can shape the beam, but they tend to
introduce artifacts, too.
Yeah, you could do this, but it really isn't necessary. Very little of
the light is "wasted" as it is.
The issue wasn't wasting light, but rather preventing glare to oncoming
traffic.
Dane Buson
2008-11-26 21:07:54 UTC
Permalink
Post by Peter Cole
Post by Tom Kunich
And of course the in-hub generators are the best of all. But none that
I've seen generate sufficient power for a decent headlight that is
effective at anything other than a dim glow that is supposed to alert
drivers not to run you over.
Pfft. I've had people tell me they thought I was a car or a motorcycle
coming up behind them. Not exactly a dim glow.
Post by Peter Cole
Post by Tom Kunich
I wonder if you could couple the hub generator with an LED headlight and
get a decent illumination for riding at, say, 25 kph on an unlit roadway.
I've maxed out at about 72 kph personally. I tend not to go quite as
fast at night.
Post by Peter Cole
I've ridden all night side-by-side with riders using very good hub
dynamos and lights. They work pretty well, a bit better than a good 2.5W
halogen like my Cateye micro's, but not as good as a 10W system. I'd
rate them adequate for normal night riding, maybe not quite so under bad
conditions (lots of oncoming glare, rain, etc.).
A good LED head on a good dynamo should be a large improvement, in
absolute amount of light, efficiency, ruggedness, and eventually, cost.
But all that is pretty well known to dynamo users.
It is rather nice. I got tired of replacing rechargeable lights when
the batteries died or connections corroded. The dynamo lights are
universally more durable and better sealed, even the crap ones.
--
Dane Buson - ***@unixbigots.org
It is by Perl alone I set my mind in motion. It is by the regex of Larry
that the code acquires flexibility, the flexibility enables obscurity, the
obscurity generates a warning. It is by Perl alone I set my mind in motion.
--Calle Dybedahl, in the Scary Devil Monastery
SMS
2008-11-24 16:54:03 UTC
Permalink
Post by j***@stanfordalumni.org
Here is what they advertise with blinding brightness. Watch that
http://www.xenonpros.com/?gclid=CMuAj7OcjpcCFQ89awod2C1DGA
$200 for a bicycle light, ouch.

If you want to carry something light that's sufficiently powerful for
when you get caught out at night, look at:

"http://eliteled.com/products/flashlights/fenix-l2d-q5.html"
and
"http://eliteled.com/products/accessory/fenix-bfm.html"

It's got a beam pattern that's very good for cycling, both in terms of
seeing and being seen, and it's got three brightness levels so you can
avoid blinding people if you're in an area with a lot of oncoming
bicycles on a narrow path.

When the woman said "you're blinding me" we were on a narrow path in
front of the Maritime museum at Aquatic park, and she was only about 18"
to the left. This is not a typical situation with oncoming traffic. If
both of us had had no lights then it would have been really bad!
Peter Cole
2008-11-26 13:54:25 UTC
Permalink
Post by SMS
Post by j***@stanfordalumni.org
Here is what they advertise with blinding brightness. Watch that
http://www.xenonpros.com/?gclid=CMuAj7OcjpcCFQ89awod2C1DGA
$200 for a bicycle light, ouch.
$55 for a flashlight -- ouch!
Post by SMS
If you want to carry something light that's sufficiently powerful for
"http://eliteled.com/products/flashlights/fenix-l2d-q5.html"
and
"http://eliteled.com/products/accessory/fenix-bfm.html"
It's got a beam pattern that's very good for cycling, both in terms of
seeing and being seen, and it's got three brightness levels so you can
avoid blinding people if you're in an area with a lot of oncoming
bicycles on a narrow path.
When the woman said "you're blinding me" we were on a narrow path in
front of the Maritime museum at Aquatic park, and she was only about 18"
to the left. This is not a typical situation with oncoming traffic. If
both of us had had no lights then it would have been really bad!
Since you're using a flashlight, the beam is symmetrical (circular),
putting out "spill" light equally above and below the pointed direction.
I don't know about the Fenix, but most LED (and MR-16) lights have a
faceted (or "orange peel") reflector, used to diffuse the light to even
out hot spots. This causes considerable spill. An easy solution to the
problem would be to fit a hood on the front to cut off upward spill.

One of the things I like about head mounted lights is that they're easy
to dip to avoid blinding oncoming traffic. If you're feeling charitable
you can even point them ahead of the oncoming cyclist to illuminate
their path -- at least until they get by. They're also useful to
simulate a high beam flash to get oncoming motorists to dim theirs.
Frank Krygowski
2008-11-26 16:10:36 UTC
Permalink
Post by Peter Cole
Since you're using a flashlight, the beam is symmetrical (circular),
putting out "spill" light equally above and below the pointed direction.
True. This is why a road lamp should have optics designed for the
job.
Post by Peter Cole
I don't know about the Fenix, but most LED (and MR-16) lights have a
faceted (or "orange peel") reflector, used to diffuse the light to even
out hot spots. This causes considerable spill. An easy solution to the
problem would be to fit a hood on the front to cut off upward spill.
It's not necessarily so easy. Depending on the source and optics,
shading the top half of the lamp may do little more than dim the
entire beam. IOW, with some lamps, even the bottom half of the lamp
generates a lot of upwards scatter.

- Frank Krygowski
Peter Cole
2008-11-27 13:36:16 UTC
Permalink
Post by Frank Krygowski
Post by Peter Cole
Since you're using a flashlight, the beam is symmetrical (circular),
putting out "spill" light equally above and below the pointed direction.
True. This is why a road lamp should have optics designed for the
job.
Post by Peter Cole
I don't know about the Fenix, but most LED (and MR-16) lights have a
faceted (or "orange peel") reflector, used to diffuse the light to even
out hot spots. This causes considerable spill. An easy solution to the
problem would be to fit a hood on the front to cut off upward spill.
It's not necessarily so easy. Depending on the source and optics,
shading the top half of the lamp may do little more than dim the
entire beam. IOW, with some lamps, even the bottom half of the lamp
generates a lot of upwards scatter.
I tried it on a smooth reflector 1W LED light and it worked very well.
The high intensity LED lights tend to have small (~1") reflectors, so it
wouldn't take much of a hood to block the ray path from the entire
reflector above a cutoff level. If the hood was reflective on the inside
surface it would put the blocked light back to the road. With a very
diffuse (orange peel) reflector you might still have a little spill
upwards, but it would still be a big improvement over a plain
symmetrical reflector/source.
SMS
2008-11-27 15:44:53 UTC
Permalink
Post by Peter Cole
I tried it on a smooth reflector 1W LED light and it worked very well.
The high intensity LED lights tend to have small (~1") reflectors, so it
wouldn't take much of a hood to block the ray path from the entire
reflector above a cutoff level. If the hood was reflective on the inside
surface it would put the blocked light back to the road. With a very
diffuse (orange peel) reflector you might still have a little spill
upwards, but it would still be a big improvement over a plain
symmetrical reflector/source.
The symmetrical beam is not a problem. Look at the beam pattern when the
light is properly aimed. The center spot illuminates the road directly
ahead, while the flood provides a "being seen" light that is not blinding.

"Loading Image..."

The same bike has a dynamo light which is much less useful because the
beam is only a "being seen light" and doesn't provide good illumination
for seeing the road. Admittedly it isn't a $200 or $300 LED dynamo lamp!

What I could do, is to build a switcher that could drive the LED
flashlight lamp from the dynamo. It's require a bridge rectifier, some
capacitors, and a buck boost switching regulator. I calculated the
losses of the conversion at about 30% minimum, using best case, ideal
components (it's probably closer to 40%), but it's an answer to a
problem that I don't have! Sticking in some Sanyo Eneloop recharageables
is not a problem. Now if I was doing randonneuring, I'd certainly go the
all-dymano route somehow.

The reason that the woman said "you're blinding me" last Saturday
evening is because she was coming almost directly toward me on a narrow
path. Normally an oncoming rider or vehicle would not be looking
straight-on into the center part of the beam. What I normally do on
bicycle trails is to go to a lower brightness if there is oncoming
traffic. Like most higher end LED lights, this light is digitally
regulated, and it has 4 different settings (9, 40, 80, 135 lumens) as
well as two flashing modes (strobe and S.O.S.). I just didn't see anyone
else coming because no one had lights. If these riders want to be
treated courteously by other riders (and most regular night riders do
have very good lights) then they need to get with the plan and have
lights themselves. That's why the rental place should offer them.

BTW, do any of the dynamo LED lights have brightness that's adjustable
in any way when you're riding fast enough that you might not need full
brightness? Once you add the switching regulator you eliminate the
problem of over-voltaging the LED and burning it out
(though you're bleeding off the excess power of the dynamo as heat).
It's just ridiculous to have the risk of burning out some of those
cheaper (but still costly) LED headlamps if the tail light burns out, or
if you go fast enough that you over-voltage/over-current it. Some of
these designers better go back and read Ohm's law again when it comes to
the relationship of voltage, resistance, and current, and not cheap out
when it comes to some simple over-voltage protection.
Peter Cole
2008-11-27 16:25:21 UTC
Permalink
Post by SMS
What I could do, is to build a switcher that could drive the LED
flashlight lamp from the dynamo. It's require a bridge rectifier, some
capacitors, and a buck boost switching regulator. I calculated the
losses of the conversion at about 30% minimum, using best case, ideal
components (it's probably closer to 40%), but it's an answer to a
problem that I don't have!
Well, it's a bad answer. You don't need all that crap. The regulators
only serve to limit the current (absolute max & various power levels)
and to boost the voltage (when the cell voltage is below LED forward
bias). The dynamo has a large series inductance which acts as a ballast,
effectively limiting the current. The simple way to get multiple power
levels is to switch LED's in & out.
Post by SMS
The reason that the woman said "you're blinding me" last Saturday
evening is because she was coming almost directly toward me on a narrow
path. Normally an oncoming rider or vehicle would not be looking
straight-on into the center part of the beam. What I normally do on
bicycle trails is to go to a lower brightness if there is oncoming
traffic. Like most higher end LED lights, this light is digitally
regulated, and it has 4 different settings (9, 40, 80, 135 lumens) as
well as two flashing modes (strobe and S.O.S.). I just didn't see anyone
else coming because no one had lights. If these riders want to be
treated courteously by other riders (and most regular night riders do
have very good lights) then they need to get with the plan and have
lights themselves. That's why the rental place should offer them.
Well perhaps, but I think blinding the light-less rider isn't improving
the situation. I find unlit riders to be a rather common situation here
in Boston. In any case, I can't see the harm in putting a hood over a
symmetrical beam to cutoff the upward spill. I've had the experience of
being dazzled by oncoming bike lights, it's not pleasant.
Post by SMS
BTW, do any of the dynamo LED lights have brightness that's adjustable
in any way when you're riding fast enough that you might not need full
brightness?
I don't get the problem, the faster I go, the more light I want.
SMS
2008-11-27 16:36:31 UTC
Permalink
Post by Peter Cole
Post by SMS
What I could do, is to build a switcher that could drive the LED
flashlight lamp from the dynamo. It's require a bridge rectifier, some
capacitors, and a buck boost switching regulator. I calculated the
losses of the conversion at about 30% minimum, using best case, ideal
components (it's probably closer to 40%), but it's an answer to a
problem that I don't have!
Well, it's a bad answer. You don't need all that crap. The regulators
only serve to limit the current (absolute max & various power levels)
and to boost the voltage (when the cell voltage is below LED forward
bias). The dynamo has a large series inductance which acts as a ballast,
effectively limiting the current. The simple way to get multiple power
levels is to switch LED's in & out.
Then LED headlights for dynamos should do that automatically rather than
use switching regulators.

Look at how you select a current limiting resistor for a simple LED
circuit. You look at the voltage that will be powering the LED, and you
calculate the current through the LED, and you look at the forward
voltage of the LED. Just because the dynamo puts out a relatively
constant current doesn't mean that you can put as much voltage as you
want across the LED.

You can play with an LED calculator at "http://led.linear1.org/1led.wiz".

I have a little hand crank dynamo that I soldered an LED to the outputs.
The faster you crank it the higher the voltage, and the brighter the
LED, until the LED burns out! Very similar to the cheaper LED dynamo
lights that warn against going over 7.5 volts. I understand why they
don't want to add the regulation circuitry; besides adding cost, it
reduces efficiency. But they could at least add some sort of
over-voltage protection as is done for incandescent dynamo lamps.
Peter Cole
2008-11-28 05:15:46 UTC
Permalink
Post by SMS
Post by Peter Cole
Post by SMS
What I could do, is to build a switcher that could drive the LED
flashlight lamp from the dynamo. It's require a bridge rectifier,
some capacitors, and a buck boost switching regulator. I calculated
the losses of the conversion at about 30% minimum, using best case,
ideal components (it's probably closer to 40%), but it's an answer to
a problem that I don't have!
Well, it's a bad answer. You don't need all that crap. The regulators
only serve to limit the current (absolute max & various power levels)
and to boost the voltage (when the cell voltage is below LED forward
bias). The dynamo has a large series inductance which acts as a
ballast, effectively limiting the current. The simple way to get
multiple power levels is to switch LED's in & out.
Then LED headlights for dynamos should do that automatically rather than
use switching regulators.
Look at how you select a current limiting resistor for a simple LED
circuit. You look at the voltage that will be powering the LED, and you
calculate the current through the LED, and you look at the forward
voltage of the LED. Just because the dynamo puts out a relatively
constant current doesn't mean that you can put as much voltage as you
want across the LED.
You can play with an LED calculator at "http://led.linear1.org/1led.wiz".
I have a little hand crank dynamo that I soldered an LED to the outputs.
The faster you crank it the higher the voltage, and the brighter the
LED, until the LED burns out! Very similar to the cheaper LED dynamo
lights that warn against going over 7.5 volts. I understand why they
don't want to add the regulation circuitry; besides adding cost, it
reduces efficiency. But they could at least add some sort of
over-voltage protection as is done for incandescent dynamo lamps.
Diodes are limited in forward bias by current, in reverse bias by
voltage. You regulate the current. The maximum current a dynamo can
produce is its short circuit current, that's determined by its
inductance and resistance. If you blew a diode it's because you exceeded
its maximum current rating, voltage isn't meaningful.
Kevin McMurtrie
2008-11-27 22:39:43 UTC
Permalink
There's a reason that most bike lights have crappy regulation. LEDs
have a somewhat logarithmic light output for input power plus a human
eye has a logarithmic sensitivity. This means that the low power
setting may be 5mA and the high power setting 1000mA. That 1:200 ratio
can't be done accurately and efficiently with cheap parts.

I built a combination hiking & biking lamp using 21 Luxeon Rebel LEDs.
I managed to perform a fully variable output by attaching the low end of
the pot to voltage feedback and the high end to current feedback. It
works very well but it requires binned LEDs and calibration to that bin.
That's probably not cost-effective for a consumer light. I also haven't
checked efficiency at low power yet. With such a huge output range,
regulator has to go between continuous and discontinuous modes at the
right time to be efficient.
--
Google is a pro-spamming service. I will not see your reply if you use Google.
Peter Cole
2008-11-28 05:47:47 UTC
Permalink
Post by Kevin McMurtrie
There's a reason that most bike lights have crappy regulation. LEDs
have a somewhat logarithmic light output for input power
Not any that I've seen.
Post by Kevin McMurtrie
plus a human
eye has a logarithmic sensitivity. This means that the low power
setting may be 5mA and the high power setting 1000mA. That 1:200 ratio
can't be done accurately and efficiently with cheap parts.
I can't imagine that wide a range being useful for a bike light, but I
don't see the problem in doing that with a simple (and cheap) PWM
(chopper) module.
Post by Kevin McMurtrie
I built a combination hiking & biking lamp using 21 Luxeon Rebel LEDs.
I managed to perform a fully variable output by attaching the low end of
the pot to voltage feedback and the high end to current feedback. It
works very well but it requires binned LEDs and calibration to that bin.
That's probably not cost-effective for a consumer light. I also haven't
checked efficiency at low power yet. With such a huge output range,
regulator has to go between continuous and discontinuous modes at the
right time to be efficient.
The problem with running diodes in parallel is that you can't control
the amount of current each diode passes (current sharing). It gets worse
because those diodes that pass more heat up more, drop forward voltage
and you get thermal runaway. You really need 1 regulator per diode or
series connected string of diodes.
Kevin McMurtrie
2008-11-28 07:30:14 UTC
Permalink
Post by Peter Cole
Post by Kevin McMurtrie
There's a reason that most bike lights have crappy regulation. LEDs
have a somewhat logarithmic light output for input power
Not any that I've seen.
Post by Kevin McMurtrie
plus a human
eye has a logarithmic sensitivity. This means that the low power
setting may be 5mA and the high power setting 1000mA. That 1:200 ratio
can't be done accurately and efficiently with cheap parts.
I can't imagine that wide a range being useful for a bike light, but I
don't see the problem in doing that with a simple (and cheap) PWM
(chopper) module.
1:200 current ratio has a much, much smaller visual ratio. That's the
problem.
Post by Peter Cole
Post by Kevin McMurtrie
I built a combination hiking & biking lamp using 21 Luxeon Rebel LEDs.
I managed to perform a fully variable output by attaching the low end of
the pot to voltage feedback and the high end to current feedback. It
works very well but it requires binned LEDs and calibration to that bin.
That's probably not cost-effective for a consumer light. I also haven't
checked efficiency at low power yet. With such a huge output range,
regulator has to go between continuous and discontinuous modes at the
right time to be efficient.
The problem with running diodes in parallel is that you can't control
the amount of current each diode passes (current sharing). It gets worse
because those diodes that pass more heat up more, drop forward voltage
and you get thermal runaway. You really need 1 regulator per diode or
series connected string of diodes.
Putting LEDs in series sums their internal resistances while averaging
their forward voltages. Matched LEDs balance well with only 2 or 3 in
series. Random LEDs (of same type) balance well with 4+ in series.

Mine is 7 groups of 3 in series of matched LEDs. They're soldered to a
0.001" thick 1 Oz foil PCB bonded to a 0.010" copper sheet with a
pyrolytic graphite heat spreader behind it. It will do 3780 lumens for
about 2 minutes (50W) before the whole thing is too hot to hold. The
crazy-high momentary output is for hiking when I need to find a distant
landmark. Normal bicycling needs about 2W input and walking about 1W
input.

I got some photos:

Copper form and heat spreader:
<http://www.pixelmemory.us/Photos/Nerd/Alien%20Bike%20Light%205.0/Copper.
jpg>

Pyrolytic graphite heat spreader:
<http://www.pixelmemory.us/Photos/Nerd/Alien%20Bike%20Light%205.0/pyrolyt
icgraphite.jpg>

LED board:
<http://www.pixelmemory.us/Photos/Nerd/Alien%20Bike%20Light%205.0/LED%20b
oard.jpg>

Regulator board:
<http://www.pixelmemory.us/Photos/Nerd/Alien%20Bike%20Light%205.0/regulat
or.jpg>

Early carbon fiber stage:
<http://www.pixelmemory.us/Photos/Nerd/Alien%20Bike%20Light%205.0/carbonf
iber.jpg>

Mounting surface for LED board:
<http://www.pixelmemory.us/Photos/Nerd/Alien%20Bike%20Light%205.0/mountsu
rface.jpg>


Done:
<http://www.pixelmemory.us/Photos/Nerd/Alien%20Bike%20Light%205.0/Front.j
pg>
<http://www.pixelmemory.us/Photos/Nerd/Alien%20Bike%20Light%205.0/Back.jp
g>

50W LED versus 100W incandescent exam light:
<http://www.pixelmemory.us/Photos/Nerd/Alien%20Bike%20Light%205.0/vs100W.
jpg>
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Google is a pro-spamming service. I will not see your reply if you use Google.
SMS
2008-11-26 16:13:45 UTC
Permalink
Post by Peter Cole
Post by SMS
Post by j***@stanfordalumni.org
Here is what they advertise with blinding brightness. Watch that
http://www.xenonpros.com/?gclid=CMuAj7OcjpcCFQ89awod2C1DGA
$200 for a bicycle light, ouch.
$55 for a flashlight -- ouch!
Yeah, I agree. It seems like a lot until you compare it with the cost of
bicycle lights that illuminate as well.

You can always get the $30 Lowe's Task Force flashlight which has become
like a cult item around here.
Tom Sherman
2008-11-25 06:57:31 UTC
Permalink
Steven M. Scharf?
--
Tom Sherman - 42.435731,-83.985007
If you are not a part of the solution, you are a part of the precipitate.
C.H. Luu
2008-11-24 04:17:50 UTC
Permalink
This is one of the nicest ride you can do in the north bay. I usually
head into the Marin headlans beforing going through Sausalito and then
onto Larkspur. The stretch of road between Tiburon and Larkspur is
especially scenic and has little traffic. Granted it's our right to
travel the roads, but it is rather dangerous at night. Most usually
do not travel with reflective apparel or lights (I'm guilty of this &
do not ride at night anymore). In high traffic areas, like those
around the Ferry and the Pier area in San Fancisco, this can make
riding very dangerous.

I honestly don't think that this will get any better. Be safe and
travel during daylight hours. If you must brave the darkness, be
prepared to put your foot down at a moment's notice. I've ridden
betweent the Pier area and the Presidio. Even in daylight, it's
hazardous. I would be hesitant to use clipless pedals in that area.

Please travel and come home in safety.

Claude
SMS
2008-11-24 05:13:37 UTC
Permalink
Post by C.H. Luu
This is one of the nicest ride you can do in the north bay. I usually
head into the Marin headlans beforing going through Sausalito and then
onto Larkspur. The stretch of road between Tiburon and Larkspur is
especially scenic and has little traffic. Granted it's our right to
travel the roads, but it is rather dangerous at night. Most usually
do not travel with reflective apparel or lights (I'm guilty of this &
do not ride at night anymore). In high traffic areas, like those
around the Ferry and the Pier area in San Fancisco, this can make
riding very dangerous.
The ferry and pier area is at least very well lit. There's a bike lane
on the Embarcadero for quite a way so you don't have to ride either in
traffic or on the sidewalk, though many people do. When we got down to
the Pier 39 area we rode in the streetcar lane.

The real problem area starts at Aquatic park where there is no street
lighting. Combined with the fog, it's really hard to see bicycles or
pedestrians without lights.
Post by C.H. Luu
I honestly don't think that this will get any better. Be safe and
travel during daylight hours. If you must brave the darkness, be
prepared to put your foot down at a moment's notice. I've ridden
betweent the Pier area and the Presidio. Even in daylight, it's
hazardous. I would be hesitant to use clipless pedals in that area.
Please travel and come home in safety.
We didn't plan to be out at night, but with it getting dark so early it
can happen. OTOH, since I had lights for everyone with me, maybe we did
plan for it!

I also noticed what a huge difference our Flash Flags made in terms of
getting vehicles to not come too close. Whether it's because they don't
want to get their vehicles scratched, or because we're more visible, I
don't know, but they make a big arc around us.
"http://www.flashback.ca/bicycle.html".
j***@stanfordalumni.org
2008-11-24 07:17:38 UTC
Permalink
Post by C.H. Luu
This is one of the nicest ride you can do in the north bay. I
usually head into the Marin headlands before going through Sausalito
and then onto Larkspur. The stretch of road between Tiburon and
Larkspur is especially scenic and has little traffic. Granted it's
our right to travel the roads, but it is rather dangerous at night.
Most usually do not travel with reflective apparel or lights (I'm
guilty of this & do not ride at night anymore). In high traffic
areas, like those around the Ferry and the Pier area in San
Francisco, this can make riding very dangerous.
I honestly don't think that this will get any better. Be safe and
travel during daylight hours. If you must brave the darkness, be
prepared to put your foot down at a moment's notice. I've ridden
between the Pier area and the Presidio. Even in daylight, it's
hazardous. I would be hesitant to use clipless pedals in that area.
Please travel and come home in safety.
This reminds me of a ride in the late 1960's when we parked on the SF
side of the GG Bridge rode to Mill Valley at dusk and climbed
Mt. Tamalpais that night under a full moon, a moon that inspired this
adventure. I recall that Kieth Vierra got a snake bite flat (the RR
ROW is rocky and rough) and because we were young and fast, it was
plenty warm. He said he wanted to find a shady spot to change his
flat under the delusion that the stark white moonlight was sunlight
and causing our sweat.

After marveling at the beautiful vista from the top of the mountain,
we descended via Panoramic Highway to HWY 1 and on down to Sausalito:

http://www.rntl.net/sausalitocam.htm

and on to the GG Bridge to the cars.

The hazard was not in meeting oncoming traffic, even though no one
had a light, but rather that in the darkness under curves in the
trees, wildlife was crossing the road. On more than one occasion we
heard, but did not see, deer running in our midst.

Discussing this later we decided, it had to be the first and last
Mt. Tamalpais full moon ride, with or without lights. In those days,
there were no cars at that time of day and no wreck.bike guys to be
incensed about "stealth" bicyclists. We were the only bikies in the
SF Bay Area that went anywhere and we knew them all by name, some of
which are pictured on Ray Hosler's site:

http://www.geocities.com/rayhosler/coastrangeslides/coast_range_slide.htm

Jobst Brandt
SMS
2008-11-24 15:37:53 UTC
Permalink
Post by j***@stanfordalumni.org
Discussing this later we decided, it had to be the first and last
Mt. Tamalpais full moon ride, with or without lights. In those days,
there were no cars at that time of day and no wreck.bike guys to be
incensed about "stealth" bicyclists.
I would have been incensed, but I was only 8 or 9 years old.

In the 1980's I used to lead full moon all-night bike rides for some
local bike clubs, including around SF, through the tunnels, down
Lombard, and across the GG bridge. These were very fun rides with little
traffic. I never felt unsafe on these rides, and OMG some people didn't
even wear helmets! We did all have lights though. I think we scared some
of the few people that were on the streets at those times.

I remember one time I co-listed the ride with the Sierra Club cycling
section from Oakland, and two days before the ride someone from that
group got it into their head that riding at night was just exceptionally
dangerous and that when people showed up I would have to tell them that
the ride was canceled. I told them that they S.O.L.. It was amusing to
see these idiots panic and complain about me to the Sierra Club's
National office, who told them to find something more important to
complain about.
SMS
2008-11-24 22:46:19 UTC
Permalink
Post by C.H. Luu
This is one of the nicest ride you can do in the north bay. I usually
head into the Marin headlans beforing going through Sausalito and then
onto Larkspur.
Yes, Conzelman road is just wonderful, except when the park rangers
decide to give speeding tickets to cyclists on the one-way downhill
section. Riding through the tunnel is also fun, though now that it's
legal to go through it's less exciting than when the military police
would wait at the east end for bicyclists to ticket.
Post by C.H. Luu
The stretch of road between Tiburon and Larkspur is
especially scenic and has little traffic. Granted it's our right to
travel the roads, but it is rather dangerous at night.
I don't know where you get the idea that riding at night, with good
lighting, is any more dangerous that riding during the daytime. That
stretch is pretty narrow with no shoulder, and I tend to take the whole
lane a lot so if the vehicles want to go by they really have to pass,
not just squeeze me off the road. The Flash Flag helps a lot as well.

With good lights on a bicycle you really stand out at night, especially
on unlit roads. In the daytime is when you are less visible, though now
I see more and more cyclists with "DRLs" consisting of very bright LED
flashing headlights and taillights that are visible even in the daytime.

When you curse bicyclists while driving at night is when you almost hit
them because they have no lights, or the lights they have are so poor
that they aren't visible even with lights. It's just insane that these
people value their life so little that they're not spending $40 or so
for some good lights.
Post by C.H. Luu
I honestly don't think that this will get any better.
But it has gotten much better already. Bicycle lighting has evolved from
the days of lights that neither made a cyclist visible, nor lit up the
road well enough to ride at an expeditious rate.
Post by C.H. Luu
travel during daylight hours. If you must brave the darkness, be
prepared to put your foot down at a moment's notice. I've ridden
betweent the Pier area and the Presidio. Even in daylight, it's
hazardous.
Between the single's Safeway (the pick-up spot for singles in the Marina
district) all the way to Fort Point it's a wide paved multi-use trail
with separate lanes for each direction of bicycles and pedestrians. Once
you enter the Presidio the traffic is very light and you don't even need
to use the trail if you don't want to.

Due to the fog, you really want to be using good lights even on full
moon nights.

I found it interesting that the biggest bicycle rental company down by
the wharf, Blazing Saddles, has a selling point of "Blazing Saddles
provide <sic> a 24 hour drop off area, so you can experience ultimate
fun, all day long, no time constraints!" That's great, especially with
the prices they charge for daily rentals, of $28-105 per day, since you
want to get your money's worth. But they really should provide equipment
that makes such riding legal.
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