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Roller dynamo slippage problem
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James
Apr 2, 2012, 6:29:07 PM4/2/12
to
I've never noticed my Sanyo Dynapower roller dynamo slip in wet weather.
AFAIK, the light is always on while the dynamo is on the tyre and the
wheels are turning at a little faster than walking pace.
Many years ago, a friend had a problem with his car alternator. No
matter how tight the belt was, the belt slipped. Turned out the
bearings were near shot, and the tighter the belt was the more friction
the bearings had - so it slipped worse as the belt was made tighter.
The point? I let my dynamo rest against the tyre with at most about 2
mm of interference, and I run a little light oil into the plain bearings
of the dynamo from time to time.
My guess is that those that had slippage problems had the dynamo pressed
hard against the tyre and the bearings dry and/or full of muck.
--
JS.
AFAIK, the light is always on while the dynamo is on the tyre and the
wheels are turning at a little faster than walking pace.
Many years ago, a friend had a problem with his car alternator. No
matter how tight the belt was, the belt slipped. Turned out the
bearings were near shot, and the tighter the belt was the more friction
the bearings had - so it slipped worse as the belt was made tighter.
The point? I let my dynamo rest against the tyre with at most about 2
mm of interference, and I run a little light oil into the plain bearings
of the dynamo from time to time.
My guess is that those that had slippage problems had the dynamo pressed
hard against the tyre and the bearings dry and/or full of muck.
--
JS.
Frank Krygowski
Apr 2, 2012, 7:20:30 PM4/2/12
to
case, the Soubitez version. We were riding the C&O Towpath, making our
way through the long Paw Paw Tunnel. The path through the tunnel was
narrow, dark, rough and muddy. Some mud had stuck to the dynamo's
roller. Anyway, I found that if I rode too slowly, the dynamo wouldn't
spin and I'd suddenly be in darkness. But riding faster than about 5
mph was scary because it was so rough and narrow. I didn't want to fall
into the canal.
I kind of gritted my teeth and plowed ahead. The headlight was sort of
intermittent, but I could tell where I was going. My wife walked her
bike using a flashlight.
I've had other times I've had to scrape mud off a roller dynamo. It
didn't cause it to stop operating, but it made it run much more roughly.
They're much better suited to paved surfaces, not mud paths.
--
- Frank Krygowski
Dan O
Apr 2, 2012, 7:38:34 PM4/2/12
to
On Apr 2, 4:20 pm, Frank Krygowski <frkrygowREM...@gEEmail.com> wrote:
> James wrote:
> > I've never noticed my Sanyo Dynapower roller dynamo slip in wet weather.
> > AFAIK, the light is always on while the dynamo is on the tyre and the
> > wheels are turning at a little faster than walking pace.
>
> > Many years ago, a friend had a problem with his car alternator. No
> > matter how tight the belt was, the belt slipped. Turned out the bearings
> > were near shot, and the tighter the belt was the more friction the
> > bearings had - so it slipped worse as the belt was made tighter.
>
> > The point? I let my dynamo rest against the tyre with at most about 2 mm
> > of interference, and I run a little light oil into the plain bearings of
> > the dynamo from time to time.
>
> > My guess is that those that had slippage problems had the dynamo pressed
> > hard against the tyre and the bearings dry and/or full of muck.
>
> I've had some minor slipping problems with a roller dynamo - in this
> case, the Soubitez version. We were riding the C&O Towpath, making our
> way through the long Paw Paw Tunnel. The path through the tunnel was
> narrow, dark, rough and muddy. Some mud had stuck to the dynamo's
> roller. Anyway, I found that if I rode too slowly, the dynamo wouldn't
> spin and I'd suddenly be in darkness. But riding faster than about 5
> mph was scary because it was so rough and narrow. I didn't want to fall
> into the canal.
>
Too bad you didn't have a nice battery powered light.
> James wrote:
> > I've never noticed my Sanyo Dynapower roller dynamo slip in wet weather.
> > AFAIK, the light is always on while the dynamo is on the tyre and the
> > wheels are turning at a little faster than walking pace.
>
> > Many years ago, a friend had a problem with his car alternator. No
> > matter how tight the belt was, the belt slipped. Turned out the bearings
> > were near shot, and the tighter the belt was the more friction the
> > bearings had - so it slipped worse as the belt was made tighter.
>
> > The point? I let my dynamo rest against the tyre with at most about 2 mm
> > of interference, and I run a little light oil into the plain bearings of
> > the dynamo from time to time.
>
> > My guess is that those that had slippage problems had the dynamo pressed
> > hard against the tyre and the bearings dry and/or full of muck.
>
> I've had some minor slipping problems with a roller dynamo - in this
> case, the Soubitez version. We were riding the C&O Towpath, making our
> way through the long Paw Paw Tunnel. The path through the tunnel was
> narrow, dark, rough and muddy. Some mud had stuck to the dynamo's
> roller. Anyway, I found that if I rode too slowly, the dynamo wouldn't
> spin and I'd suddenly be in darkness. But riding faster than about 5
> mph was scary because it was so rough and narrow. I didn't want to fall
> into the canal.
>
> I kind of gritted my teeth and plowed ahead. The headlight was sort of
> intermittent, but I could tell where I was going. My wife walked her
> bike using a flashlight.
>
> I've had other times I've had to scrape mud off a roller dynamo. It
> didn't cause it to stop operating, but it made it run much more roughly.
> They're much better suited to paved surfaces, not mud paths.
>
seem.
Dan O
Apr 2, 2012, 7:16:50 PM4/2/12
to
Jay Beattie
Apr 2, 2012, 8:44:15 PM4/2/12
to
by darkness and water. Sounds like a treatment for the next Speilberg
film. Frank played by Harrison Ford.
Dan, it's not raining. Go ride your bike. I'm going home and mow my
lawn.
-- Jay Beattie.
James
Apr 2, 2012, 9:06:17 PM4/2/12
to
conditions. My brother used a rubber band around the actuating lever to
hold it against the tyre with more force, and I've read and heard of
others who try to rubber coat the roller, or even glue grit to the
roller so it might grip the tyre better.
I still think this may have been unnecessary and/or counter productive,
where lubrication and lighter contact pressure may have helped.
--
JS.
James
Apr 2, 2012, 9:09:09 PM4/2/12
to
Hub dynamos are not subject to the slipping roller problem, but have
other cons.
--
JS.
Frank Krygowski
Apr 2, 2012, 10:21:30 PM4/2/12
to
Jay Beattie wrote:
>
>
> Holy Crap! Stuck in the gaping maw of the Paw Paw Tunnel, surrounded
> by darkness and water. Sounds like a treatment for the next Speilberg
> film. Frank played by Harrison Ford.
Feh. I'm not _that_ old!
>
>
> Holy Crap! Stuck in the gaping maw of the Paw Paw Tunnel, surrounded
> by darkness and water. Sounds like a treatment for the next Speilberg
> film. Frank played by Harrison Ford.
--
- Frank Krygowski
Frank Krygowski
Apr 2, 2012, 10:22:02 PM4/2/12
to
--
- Frank Krygowski
Frank Krygowski
Apr 2, 2012, 10:34:25 PM4/2/12
to
section of the roller. Once a rear wheel gets fairly worn, the extreme
perimeter of the tire becomes almost cylindrical, rather than its
original toroid shape. So the contact patch between the roller and tire
is the same rectangular patch that a car tire has with the ground.
Seems to me that as with a car tire, water would not be squeegied aside
(is that a recognized verb?) as it is with a toroidal tire.
So I'd make the roller a toroid - maybe by machining a ring of suitable
cross section and lightly pressing it onto the roller. If the problem
were significant for me, that is.
I did something similar (and simpler) with a standard Union bottle
dynamo. I removed the knurled drive roller, chucked it in a lathe, and
cut a groove not far from the top into which I snapped a thick O-ring of
suitable diameter. Cross section of the O-ring is probably 0.1" or 2.5
mm. On one bike, I've got that set so the O-ring runs on the rim
sidewall instead of the tire. It's remarkably smooth. I confess,
though, I don't think I've ever ridden that in the rain at night, so I
don't know if it would slip.
> I still think this may have been unnecessary and/or counter productive,
> where lubrication and lighter contact pressure may have helped.
of slippage, unless something really weird was happening with your
bearings. The situation is similar to aquaplaning, I think, and I think
it's pretty well documented that greater load reduces aquaplaning tendency.
--
- Frank Krygowski
James
Apr 2, 2012, 11:04:29 PM4/2/12
to
You may be right WRT the tyre profile, though my rear tyre usually gets
fairly flat topped before I replace it, and I've never noticed slippage.
--
JS
datakoll
Apr 2, 2012, 11:15:22 PM4/2/12
to
datakoll
Apr 3, 2012, 12:58:50 AM4/3/12
to
BELT GOES ON SIDEWALL
Stephen Bauman
Apr 3, 2012, 7:56:26 AM4/3/12
to
On Tue, 03 Apr 2012 08:29:07 +1000, James wrote:
> I've never noticed my Sanyo Dynapower roller dynamo slip in wet weather.
> AFAIK, the light is always on while the dynamo is on the tyre and the
> wheels are turning at a little faster than walking pace.
>
<snip>
> I've never noticed my Sanyo Dynapower roller dynamo slip in wet weather.
> AFAIK, the light is always on while the dynamo is on the tyre and the
> wheels are turning at a little faster than walking pace.
>
I experienced significant slippage in wet weather to the point that I
replaced it with the Soubitez equivalent. The Sanyo had a very light
spring whereas the Soubitez' was much stronger.
Sanyo's light spring also meant it would bounce off the tire whenever I
went over bumps. Sometimes the bounce was so great that it would snap
back and engage the stop. Like others, I cured this by using rubber bands
to get more pressure against the tire.
Sanyo has upgraded its classic Dynapower bottom bracket generator with
the NH-T10 model.
http://www.peterwhitecycles.com/sanyo.asp
I installed one, along with modern LED lights. The dynamo appears to
eliminate all the problems with the old model. There is a rubber covering
for the roller wheel that eliminates slippage and the spring is much
stronger. Also, the LED lights come to full brightness at only 1 watt so
there much less effort is required. This also reduces slippage.
Stephen Bauman
Dan O
Apr 3, 2012, 10:17:13 AM4/3/12
to
datakoll
Apr 3, 2012, 10:31:27 AM4/3/12
to
On Monday, April 2, 2012 10:58:50 PM UTC-6, datakoll wrote:
> BELT GOES ON SIDEWALL
> BELT GOES ON SIDEWALL
Lou Holtman
Apr 3, 2012, 5:23:22 PM4/3/12
to
Op 3-4-2012 4:34, Frank Krygowski schreef:
We have the solution for all these problems from the past around here.
All medium priced bikes and up have this solution fitted standard.
Lou, bottle generators geezzz...
All medium priced bikes and up have this solution fitted standard.
Lou, bottle generators geezzz...
Frank Krygowski
Apr 3, 2012, 7:26:14 PM4/3/12
to
Lou Holtman wrote:
> Op 3-4-2012 4:34, Frank Krygowski schreef:
>>
> Op 3-4-2012 4:34, Frank Krygowski schreef:
>>
>> BTW, I doubt that too much contact pressure would increase the chances
>> of slippage, unless something really weird was happening with your
>> bearings. The situation is similar to aquaplaning, I think, and I think
>> it's pretty well documented that greater load reduces aquaplaning
>> tendency.
>>
>
> We have the solution for all these problems from the past around here.
> All medium priced bikes and up have this solution fitted standard.
>
> Lou, bottle generators geezzz...
Is that solution fitted to bikes designed for fast riding? I thought
>> of slippage, unless something really weird was happening with your
>> bearings. The situation is similar to aquaplaning, I think, and I think
>> it's pretty well documented that greater load reduces aquaplaning
>> tendency.
>>
>
> We have the solution for all these problems from the past around here.
> All medium priced bikes and up have this solution fitted standard.
>
> Lou, bottle generators geezzz...
the answer was no.
I've got hub dynamos on two bikes. They're very nice, and never slip.
But there certainly are disadvantages that go with the advantages - as
with almost everything else.
--
- Frank Krygowski
Dan O
Apr 3, 2012, 7:32:23 PM4/3/12
to
good ones.
James
Apr 3, 2012, 8:47:57 PM4/3/12
to
including:
"Slippage: In wet conditions, the roller on a bottle dynamo can slip
against the surface of a tire, which interrupts or reduces the amount of
electricity generated. This can cause the lights to go out completely or
intermittently."
--
JS.
Jay Beattie
Apr 3, 2012, 8:47:59 PM4/3/12
to
>
I don't think a dyno hub would have been too happy after yesterday's
ride home on the flooded Greenway path -- like this:
http://bikeportland.org/2011/05/31/high-water-on-the-willamette-photos-updates-on-flood-locations-53967
That second picture looking south (submitted by Paul Souders)is pretty
close to what it looked like in that area yesterday. Water over my
front hub . . . hey, I had to give it a shot. Who cares if I get
water in my bearings. It just displaces the previous water in my
bearings. How often to you get to pedal underwater? The hard part is
figuring out where the path is and staying on it.
-- Jay Beattie.
James
Apr 3, 2012, 9:00:03 PM4/3/12
to
On 03/04/12 21:56, Stephen Bauman wrote:
> On Tue, 03 Apr 2012 08:29:07 +1000, James wrote:
>
>> I've never noticed my Sanyo Dynapower roller dynamo slip in wet weather.
>> AFAIK, the light is always on while the dynamo is on the tyre and the
>> wheels are turning at a little faster than walking pace.
>>
>
> <snip>
>
> I experienced significant slippage in wet weather to the point that I
> replaced it with the Soubitez equivalent. The Sanyo had a very light
> spring whereas the Soubitez' was much stronger.
>
> Sanyo's light spring also meant it would bounce off the tire whenever I
> went over bumps. Sometimes the bounce was so great that it would snap
> back and engage the stop. Like others, I cured this by using rubber bands
> to get more pressure against the tire.
I've never had that problem, but mine is not mounted at the BB, rather
> On Tue, 03 Apr 2012 08:29:07 +1000, James wrote:
>
>> I've never noticed my Sanyo Dynapower roller dynamo slip in wet weather.
>> AFAIK, the light is always on while the dynamo is on the tyre and the
>> wheels are turning at a little faster than walking pace.
>>
>
> <snip>
>
> I experienced significant slippage in wet weather to the point that I
> replaced it with the Soubitez equivalent. The Sanyo had a very light
> spring whereas the Soubitez' was much stronger.
>
> Sanyo's light spring also meant it would bounce off the tire whenever I
> went over bumps. Sometimes the bounce was so great that it would snap
> back and engage the stop. Like others, I cured this by using rubber bands
> to get more pressure against the tire.
in front of the rear brake bridge. As a result it falls on to the wheel
rather than away from it.
> Sanyo has upgraded its classic Dynapower bottom bracket generator with
> the NH-T10 model.
>
> http://www.peterwhitecycles.com/sanyo.asp
a cable to engage it? How does it latch on and release? Can you
lubricate the plain bearings?
> I installed one, along with modern LED lights. The dynamo appears to
> eliminate all the problems with the old model. There is a rubber covering
> for the roller wheel that eliminates slippage and the spring is much
> stronger. Also, the LED lights come to full brightness at only 1 watt so
> there much less effort is required. This also reduces slippage.
I haven't had mine slip. Although, I would have thought the power
consumption was close to 3W with my setup. It is a little difficult to
calculate because the voltage and current waveforms are not so
sinusoidal when powering a bridge of LEDs.
--
JS.
datakoll
Apr 3, 2012, 10:17:29 PM4/3/12
to
pulled a bottle generator from the dumpster. I was impressed. Nice design, feel. Didn't work. bummer.
frankly, the hub has it. cost is irrelevant
batteries are expensive. 2 bottles equal what ?
occasinally I speak with Rialta owners-the VW based RV home.
They truly tune in when I go into my oldest Volvo owner care and oil routine. Like they are fixed on evry word.
work out gas mileage saving over V8 RV van based then subtract motor life due to the Rialta getting overstressed-like the microbust-or isthat the MACROBUST=by unsymathetic owners running 75mph all day thru the Rockies
and you're left in the hole
frankly, the hub has it. cost is irrelevant
batteries are expensive. 2 bottles equal what ?
occasinally I speak with Rialta owners-the VW based RV home.
They truly tune in when I go into my oldest Volvo owner care and oil routine. Like they are fixed on evry word.
work out gas mileage saving over V8 RV van based then subtract motor life due to the Rialta getting overstressed-like the microbust-or isthat the MACROBUST=by unsymathetic owners running 75mph all day thru the Rockies
and you're left in the hole
Lou Holtman
Apr 4, 2012, 2:32:59 AM4/4/12
to
Op woensdag 4 april 2012 01:26:14 UTC+2 schreef Frank Krygowski het volgende:
> I've got hub dynamos on two bikes. They're very nice, and never slip.
> But there certainly are disadvantages that go with the advantages - as
> with almost everything else.
Beside cost what are the disadvantages compared to a slipping bottle generator? The extra cost are neglectible when fitted from factory. That is what we learned to understand here.
Lou
> Lou Holtman wrote:
> > Op 3-4-2012 4:34, Frank Krygowski schreef:
> >>
> >> BTW, I doubt that too much contact pressure would increase the chances
> >> of slippage, unless something really weird was happening with your
> >> bearings. The situation is similar to aquaplaning, I think, and I think
> >> it's pretty well documented that greater load reduces aquaplaning
> >> tendency.
> >>
> >
> > We have the solution for all these problems from the past around here.
> > All medium priced bikes and up have this solution fitted standard.
> >
> > Lou, bottle generators geezzz...
>
> Is that solution fitted to bikes designed for fast riding? I thought
> the answer was no.
We have no speed limits for bikes IIRC but you are correct that the bikes I was referring to are mostly used for commuting or other utility riding. On the other hand I can't imagine that on your side of the pond people are using the bikes with bottle generators for racing at 40 km/hr. I have two hub generators on two bikes which I use for 'fast' riding. There is no problem. The choice between a bottle generator, battery powered or a hub generator is a no brainer for me for any bike. Am I so different?
> > Op 3-4-2012 4:34, Frank Krygowski schreef:
> >>
> >> BTW, I doubt that too much contact pressure would increase the chances
> >> of slippage, unless something really weird was happening with your
> >> bearings. The situation is similar to aquaplaning, I think, and I think
> >> it's pretty well documented that greater load reduces aquaplaning
> >> tendency.
> >>
> >
> > We have the solution for all these problems from the past around here.
> > All medium priced bikes and up have this solution fitted standard.
> >
> > Lou, bottle generators geezzz...
>
> Is that solution fitted to bikes designed for fast riding? I thought
> the answer was no.
> I've got hub dynamos on two bikes. They're very nice, and never slip.
> But there certainly are disadvantages that go with the advantages - as
> with almost everything else.
Lou
Lou Holtman
Apr 4, 2012, 2:34:27 AM4/4/12
to
Op woensdag 4 april 2012 01:32:23 UTC+2 schreef Dan O het volgende:
That is the only disadvantage I can think of but like I said the extra cost is small when fitted of factory.
Lou
Lou
Lou Holtman
Apr 4, 2012, 2:41:49 AM4/4/12
to
Op woensdag 4 april 2012 02:47:59 UTC+2 schreef Jay Beattie het volgende:
We have high water from time to time:
<https://picasaweb.google.com/101076538433373858645/HoogwaterJan2011#5562550132591519026>
we manage.
Lou
Op woensdag 4 april 2012 02:47:59 UTC+2 schreef Jay Beattie het volgende:
We have high water from time to time:
<https://picasaweb.google.com/101076538433373858645/HoogwaterJan2011#5562550132591519026>
we manage. If the water is hub deep it is unridable in my opinion. I would be more concerned about my BB.
Lou
<https://picasaweb.google.com/101076538433373858645/HoogwaterJan2011#5562550132591519026>
we manage.
Lou
Op woensdag 4 april 2012 02:47:59 UTC+2 schreef Jay Beattie het volgende:
<https://picasaweb.google.com/101076538433373858645/HoogwaterJan2011#5562550132591519026>
we manage. If the water is hub deep it is unridable in my opinion. I would be more concerned about my BB.
Lou
Stephen Bauman
Apr 4, 2012, 6:48:16 AM4/4/12
to
On Wed, 04 Apr 2012 11:00:03 +1000, James wrote:
<snip>
>> Sanyo has upgraded its classic Dynapower bottom bracket generator with
>> the NH-T10 model.
>>
>> http://www.peterwhitecycles.com/sanyo.asp
>
> Yes, I've looked at that. Does it still damage the paint? Must you use
> a cable to engage it? How does it latch on and release? Can you
> lubricate the plain bearings?
>
The body is still electrically connected to the dynamo. However, they
also have two wires connected. So, one can tape the mounting to protect
the paint and still have a solid electrical connection.
A (bowdin) cable connection is required to disengage this model. The
cable ends in a lever that must be mounted on the frame. The supplied
clamp was too small for any tube on my bike. What I did was use a Zefel
water bottle cage boss for mounting. The actuating lever action resembles
a downtube shifter. It's enclosed. There's a pin that engages the lever
when the dynamo is not engaged. This provides a positive lock.
The literature indicates that sealed bearings are used and can be
replaced easily. I've not tried this yet.
>> I installed one, along with modern LED lights. The dynamo appears to
>> eliminate all the problems with the old model. There is a rubber
>> covering for the roller wheel that eliminates slippage and the spring
>> is much stronger. Also, the LED lights come to full brightness at only
>> 1 watt so there much less effort is required. This also reduces
>> slippage.
>
> The reduced wattage I can go along with. Perhaps that's another reason
> I haven't had mine slip. Although, I would have thought the power
> consumption was close to 3W with my setup. It is a little difficult to
> calculate because the voltage and current waveforms are not so
> sinusoidal when powering a bridge of LEDs.
The B&M LED lights (head and tail) pack quite a bit of electronics and
optics in them. I'm an EE by profession. I made a build/buy decision that
I'd be hard pressed to duplicate the their performance for less than the
$100 selling price for the front light. I'm getting a fairly well shaped
beam pattern as well as a standlight for the money.
Stephen Bauman
<snip>
>> Sanyo has upgraded its classic Dynapower bottom bracket generator with
>> the NH-T10 model.
>>
>> http://www.peterwhitecycles.com/sanyo.asp
>
> Yes, I've looked at that. Does it still damage the paint? Must you use
> a cable to engage it? How does it latch on and release? Can you
> lubricate the plain bearings?
>
also have two wires connected. So, one can tape the mounting to protect
the paint and still have a solid electrical connection.
A (bowdin) cable connection is required to disengage this model. The
cable ends in a lever that must be mounted on the frame. The supplied
clamp was too small for any tube on my bike. What I did was use a Zefel
water bottle cage boss for mounting. The actuating lever action resembles
a downtube shifter. It's enclosed. There's a pin that engages the lever
when the dynamo is not engaged. This provides a positive lock.
The literature indicates that sealed bearings are used and can be
replaced easily. I've not tried this yet.
>> I installed one, along with modern LED lights. The dynamo appears to
>> eliminate all the problems with the old model. There is a rubber
>> covering for the roller wheel that eliminates slippage and the spring
>> is much stronger. Also, the LED lights come to full brightness at only
>> 1 watt so there much less effort is required. This also reduces
>> slippage.
>
> The reduced wattage I can go along with. Perhaps that's another reason
> I haven't had mine slip. Although, I would have thought the power
> consumption was close to 3W with my setup. It is a little difficult to
> calculate because the voltage and current waveforms are not so
> sinusoidal when powering a bridge of LEDs.
optics in them. I'm an EE by profession. I made a build/buy decision that
I'd be hard pressed to duplicate the their performance for less than the
$100 selling price for the front light. I'm getting a fairly well shaped
beam pattern as well as a standlight for the money.
Stephen Bauman
Jay Beattie
Apr 4, 2012, 11:46:04 AM4/4/12
to
On Apr 3, 11:41 pm, Lou Holtman <lou.holt...@gmail.com> wrote:
> Op woensdag 4 april 2012 02:47:59 UTC+2 schreef Jay Beattie het volgende:
>
>
>
>
>
> > On Apr 3, 4:32 pm, Dan O <danover...@gmail.com> wrote:
> > > On Apr 3, 4:26 pm, Frank Krygowski <frkrygowREM...@gEEmail.com> wrote:
>
> > > > Lou Holtman wrote:
> > > > > Op 3-4-2012 4:34, Frank Krygowski schreef:
>
> > > > >> BTW, I doubt that too much contact pressure would increase the chances
> > > > >> of slippage, unless something really weird was happening with your
> > > > >> bearings. The situation is similar to aquaplaning, I think, and I think
> > > > >> it's pretty well documented that greater load reduces aquaplaning
> > > > >> tendency.
>
> > > > > We have the solution for all these problems from the past around here.
> > > > > All medium priced bikes and up have this solution fitted standard.
>
> > > > > Lou, bottle generators geezzz...
>
> > > > Is that solution fitted to bikes designed for fast riding? I thought
> > > > the answer was no.
>
> > > > I've got hub dynamos on two bikes. They're very nice, and never slip.
> > > > But there certainly are disadvantages that go with the advantages - as
> > > > with almost everything else.
>
> > > I think initial cost being about the only disadvantage to the really
> > > good ones.- Hide quoted text -
>
> > I don't think a dyno hub would have been too happy after yesterday's
> > ride home on the flooded Greenway path -- like this:
>
> >http://bikeportland.org/2011/05/31/high-water-on-the-willamette-photo...
> Op woensdag 4 april 2012 02:47:59 UTC+2 schreef Jay Beattie het volgende:
>
>
>
>
>
> > On Apr 3, 4:32 pm, Dan O <danover...@gmail.com> wrote:
> > > On Apr 3, 4:26 pm, Frank Krygowski <frkrygowREM...@gEEmail.com> wrote:
>
> > > > Lou Holtman wrote:
> > > > > Op 3-4-2012 4:34, Frank Krygowski schreef:
>
> > > > >> BTW, I doubt that too much contact pressure would increase the chances
> > > > >> of slippage, unless something really weird was happening with your
> > > > >> bearings. The situation is similar to aquaplaning, I think, and I think
> > > > >> it's pretty well documented that greater load reduces aquaplaning
> > > > >> tendency.
>
> > > > > We have the solution for all these problems from the past around here.
> > > > > All medium priced bikes and up have this solution fitted standard.
>
> > > > > Lou, bottle generators geezzz...
>
> > > > Is that solution fitted to bikes designed for fast riding? I thought
> > > > the answer was no.
>
> > > > I've got hub dynamos on two bikes. They're very nice, and never slip.
> > > > But there certainly are disadvantages that go with the advantages - as
> > > > with almost everything else.
>
> > > I think initial cost being about the only disadvantage to the really
> > > good ones.- Hide quoted text -
>
> > I don't think a dyno hub would have been too happy after yesterday's
> > ride home on the flooded Greenway path -- like this:
>
>
> > That second picture looking south (submitted by Paul Souders)is pretty
> > close to what it looked like in that area yesterday. Water over my
> > front hub . . . hey, I had to give it a shot. Who cares if I get
> > water in my bearings. It just displaces the previous water in my
> > bearings. How often to you get to pedal underwater? The hard part is
> > figuring out where the path is and staying on it.
>
> > -- Jay Beattie.
>
> We have high water from time to time:
>
> <https://picasaweb.google.com/101076538433373858645/HoogwaterJan2011#5...>
> > That second picture looking south (submitted by Paul Souders)is pretty
> > close to what it looked like in that area yesterday. Water over my
> > front hub . . . hey, I had to give it a shot. Who cares if I get
> > water in my bearings. It just displaces the previous water in my
> > bearings. How often to you get to pedal underwater? The hard part is
> > figuring out where the path is and staying on it.
>
> > -- Jay Beattie.
>
> We have high water from time to time:
>
>
> we manage.
>
> Lou
>
> Op woensdag 4 april 2012 02:47:59 UTC+2 schreef Jay Beattie het volgende:
>
>
>
>
>
> > On Apr 3, 4:32 pm, Dan O <danover...@gmail.com> wrote:
> > > On Apr 3, 4:26 pm, Frank Krygowski <frkrygowREM...@gEEmail.com> wrote:
>
> > > > Lou Holtman wrote:
> > > > > Op 3-4-2012 4:34, Frank Krygowski schreef:
>
> > > > >> BTW, I doubt that too much contact pressure would increase the chances
> > > > >> of slippage, unless something really weird was happening with your
> > > > >> bearings. The situation is similar to aquaplaning, I think, and I think
> > > > >> it's pretty well documented that greater load reduces aquaplaning
> > > > >> tendency.
>
> > > > > We have the solution for all these problems from the past around here.
> > > > > All medium priced bikes and up have this solution fitted standard.
>
> > > > > Lou, bottle generators geezzz...
>
> > > > Is that solution fitted to bikes designed for fast riding? I thought
> > > > the answer was no.
>
> > > > I've got hub dynamos on two bikes. They're very nice, and never slip.
> > > > But there certainly are disadvantages that go with the advantages - as
> > > > with almost everything else.
>
> > > I think initial cost being about the only disadvantage to the really
> > > good ones.- Hide quoted text -
>
> > I don't think a dyno hub would have been too happy after yesterday's
> > ride home on the flooded Greenway path -- like this:
>
> >http://bikeportland.org/2011/05/31/high-water-on-the-willamette-photo...
> we manage.
>
> Lou
>
> Op woensdag 4 april 2012 02:47:59 UTC+2 schreef Jay Beattie het volgende:
>
>
>
>
>
> > On Apr 3, 4:32 pm, Dan O <danover...@gmail.com> wrote:
> > > On Apr 3, 4:26 pm, Frank Krygowski <frkrygowREM...@gEEmail.com> wrote:
>
> > > > Lou Holtman wrote:
> > > > > Op 3-4-2012 4:34, Frank Krygowski schreef:
>
> > > > >> BTW, I doubt that too much contact pressure would increase the chances
> > > > >> of slippage, unless something really weird was happening with your
> > > > >> bearings. The situation is similar to aquaplaning, I think, and I think
> > > > >> it's pretty well documented that greater load reduces aquaplaning
> > > > >> tendency.
>
> > > > > We have the solution for all these problems from the past around here.
> > > > > All medium priced bikes and up have this solution fitted standard.
>
> > > > > Lou, bottle generators geezzz...
>
> > > > Is that solution fitted to bikes designed for fast riding? I thought
> > > > the answer was no.
>
> > > > I've got hub dynamos on two bikes. They're very nice, and never slip.
> > > > But there certainly are disadvantages that go with the advantages - as
> > > > with almost everything else.
>
> > > I think initial cost being about the only disadvantage to the really
> > > good ones.- Hide quoted text -
>
> > I don't think a dyno hub would have been too happy after yesterday's
> > ride home on the flooded Greenway path -- like this:
>
>
> > That second picture looking south (submitted by Paul Souders)is pretty
> > close to what it looked like in that area yesterday. Water over my
> > front hub . . . hey, I had to give it a shot. Who cares if I get
> > water in my bearings. It just displaces the previous water in my
> > bearings. How often to you get to pedal underwater? The hard part is
> > figuring out where the path is and staying on it.
>
> > -- Jay Beattie.
>
> We have high water from time to time:
>
> <https://picasaweb.google.com/101076538433373858645/HoogwaterJan2011#5...>
> > That second picture looking south (submitted by Paul Souders)is pretty
> > close to what it looked like in that area yesterday. Water over my
> > front hub . . . hey, I had to give it a shot. Who cares if I get
> > water in my bearings. It just displaces the previous water in my
> > bearings. How often to you get to pedal underwater? The hard part is
> > figuring out where the path is and staying on it.
>
> > -- Jay Beattie.
>
> We have high water from time to time:
>
>
> we manage. If the water is hub deep it is unridable in my opinion. I would be more concerned about my BB.
>
> Lou- Hide quoted text -
> we manage. If the water is hub deep it is unridable in my opinion. I would be more concerned about my BB.
>
>
> - Show quoted text -- Hide quoted text -
>
> - Show quoted text -
My commuter bike is headed for rebuild, so I figured it would be fun
to do some underwater riding, plus I didn't want to turn around and go
back to high ground. This is not something I would recommend doing on
a regular basis.
As for dynamos, I like the idea of them, but now that it is getting
light at night, it's not anything I need to buy. In fact, I'll be
going to lighter equipment in preparation for commuter racing.
http://www.youtube.com/watch?v=CI7T2iuGjjc
-- Jay Beattie.
Frank Krygowski
Apr 4, 2012, 12:14:23 PM4/4/12
to
Stephen Bauman wrote:
>
>
> The B&M LED lights (head and tail) pack quite a bit of electronics and
> optics in them. I'm an EE by profession.
I admire B&M's optics. They've done a good job. Their optical
>
>
> The B&M LED lights (head and tail) pack quite a bit of electronics and
> optics in them. I'm an EE by profession.
efficiency is hard to duplicate using the tools in my basement!
Regarding electronics: I'm an ME (retired) so not as competent as you
with electronics. But I'm curious about the specifics of the
electronics in those lights. My curiosity comes from the fact that the
critical parameter for an LED is current, and bike generators are
essentially constant current devices, 0.5 Amp. Obviously, there's need
for rectification, and for a capacitor if you want a standlight. But
what else are B&M doing in there?
It seems many home brewers (like James) are doing fine just with
rectification, or just using multiple LEDs to handle the different
phases of the AC waveform. So what else is needed?
--
- Frank Krygowski
Dan O
Apr 4, 2012, 1:07:36 PM4/4/12
to
(pretty dumb thing to do in retrospect, as it was deep enough to
conceal like a shopping cart or something).
Sustained submersion is a pretty arcane requirement, but obviously
anything that can't stand getting soaked is going to be a problem
around here.
> As for dynamos, I like the idea of them, but now that it is getting
> light at night, it's not anything I need to buy. In fact, I'll be
> going to lighter equipment in preparation for commuter racing.http://www.youtube.com/watch?v=CI7T2iuGjjc
>
town, they will blow by my ol' loaded truckster, but then almost
always resume their more sustainable pace. That's when I might keep
'em in my sights and start reeling them in. (I they only knew I had
>20 miles and a number of hills to go yet.)
Peter Cole
Apr 4, 2012, 2:12:09 PM4/4/12
to
in that wattage.
They charge a lot of $$ for a bit of plastic and cheap electronics, but
that's the bike biz.
Chalo
Apr 4, 2012, 2:27:49 PM4/4/12
to
Frank Krygowski wrote:
>
> Stephen Bauman wrote:
> >
> > The B&M LED lights (head and tail) pack quite a bit of electronics and
> > optics in them. I'm an EE by profession.
>
> I admire B&M's optics. They've done a good job. Their optical
> efficiency is hard to duplicate using the tools in my basement!
Good thing you don't have to, and at a nominal 3W generator output
>
> Stephen Bauman wrote:
> >
> > The B&M LED lights (head and tail) pack quite a bit of electronics and
> > optics in them. I'm an EE by profession.
>
> I admire B&M's optics. They've done a good job. Their optical
> efficiency is hard to duplicate using the tools in my basement!
there are good reasons not to!
Chalo
Jay Beattie
Apr 4, 2012, 2:36:11 PM4/4/12
to
My commute is a lot shorter, and during spring and summer, it's a
f****** drag race in places, particularly on the climb through the
cemetery (starting at about 2:50 on that video). That's a super-
popular route, and everyone wants to be a climbing star. Other riders
are even popping up on my peaceful, secret routes through the West
Hills. I should just learn to be old and slow and enjoy the view, but
I can't.
-- Jay Beattie.
-- Jay Beattie.
Frank Krygowski
Apr 4, 2012, 2:37:54 PM4/4/12
to
are naturally constant current, and they put out pretty close to 0.5
Amp rms. That seems a useful value in the high powered LEDs I've seen
and used, with only rectification needed. So why regulate something
that's already constant?
Again, I'm not an EE, so please feel free to tell me what I'm missing.
- Frank Krygowski
Frank Krygowski
Apr 4, 2012, 2:40:51 PM4/4/12
to
I've built a couple LED headlights. Although I'm not positive, I
suspect the total lumen output of my home brews is the same as that of
the IQ Cyo I own. But the Cyo will light up a stop sign nearly 1/4
mile away, and beautifully light the road at the same time. The home
brews don't do the same. If I could duplicate those optics, I
certainly would.
- Frank Krygowski
Peter Cole
Apr 4, 2012, 4:55:49 PM4/4/12
to
of power sources, like different voltage generators, and/or batteries.
My point is that even full regulation at 3W is extremely cheap and
simple these days.
With the efficiency of modern LED's, it's easy to put out a lot of
light. With incandescent bulbs, the problem was to use a marginally
adequate amount of light optimally. The new lights are powerful enough
that the problem becomes one of not dazzling oncoming traffic. I think
these are different problems; while they both may involve some beam
shaping/shading, the latter design is much easier. You just have to
provide a vertical cutoff, side spill is advantageous and you have light
to spare.
As bike lights approach MV lights in intensity, the short wheelbase and
lack of suspension of bicycles can create problems for lights with even
a carefully shaped beam. I find it more natural to use a miner's style
light than an auto's.
Frank Krygowski
Apr 4, 2012, 5:01:18 PM4/4/12
to
Lou Holtman wrote:
> Op woensdag 4 april 2012 01:26:14 UTC+2 schreef Frank Krygowski het volgende:
> Op woensdag 4 april 2012 01:26:14 UTC+2 schreef Frank Krygowski het volgende:
>>> All medium priced bikes and up have this solution fitted standard.
>>> Lou, bottle generators geezzz...
>>
>> Is that solution fitted to bikes designed for fast riding? I thought
>> the answer was no.
>
> We have no speed limits for bikes IIRC but you are correct that the bikes I was referring to are mostly used for commuting or other utility riding. On the other hand I can't imagine that on your side of the pond people are using the bikes with bottle generators for racing at 40 km/hr. I have two hub generators on two bikes which I use for 'fast' riding. There is no problem. The choice between a bottle generator, battery powered or a hub generator is a no brainer for me for any bike. Am I so different?
OK. All of the heavier bikes, then, but not the lighter,
>>> Lou, bottle generators geezzz...
>>
>> Is that solution fitted to bikes designed for fast riding? I thought
>> the answer was no.
>
> We have no speed limits for bikes IIRC but you are correct that the bikes I was referring to are mostly used for commuting or other utility riding. On the other hand I can't imagine that on your side of the pond people are using the bikes with bottle generators for racing at 40 km/hr. I have two hub generators on two bikes which I use for 'fast' riding. There is no problem. The choice between a bottle generator, battery powered or a hub generator is a no brainer for me for any bike. Am I so different?
performance-oriented bikes. (The rule is based on weight, isn't it?)
>> I've got hub dynamos on two bikes. They're very nice, and never slip.
>> But there certainly are disadvantages that go with the advantages - as
>> with almost everything else.
>
>
> Beside cost what are the disadvantages compared to a slipping bottle generator? The extra cost are neglectible when fitted from factory. That is what we learned to understand here.
for a very few and uncommon bikes, hub dynamos are not available as
original equipment. So someone wanting a dynamo of any type will have
to buy it as an aftermarket accessory.
And over here, hub dynamos are much more rare than other types (not that
any type is common, except in my basement). So if a person wanders into
a bike shop and asks to buy one aftermarket, he'll have a more difficult
time finding a hub unit.
Once that's done, he'll have to install it, or have it installed.
That's more difficult or costly with a hub unit. Installing a bottle or
roller unit is within the skills of most people who work on their own
bikes, but most of them don't build wheels.
If a hub unit is installed, it's more difficult to share it among bikes.
The Soubitez roller unit that's now on my wife's Bike Friday used to
be on her Cannondale. The change was easy, but it wouldn't have been
with a hub unit, given 20" vs. 700c wheels. (My utility bike has a hub
dynamo, but it's a different wheel size yet - 27".)
There's a minor weight penalty to a hub, and there's the issue of minor
(for most) drag when off. Those don't matter to me, but they do to some
people.
I do really like the hub units I have. But overall, it's obvious that
there must be _some_ disadvantages to hub dynamos, or they wouldn't
still sell bottle and roller units!
--
- Frank Krygowski
Peter Cole
Apr 4, 2012, 5:14:42 PM4/4/12
to
James
Apr 4, 2012, 5:28:22 PM4/4/12
to
On 04/04/12 16:32, Lou Holtman wrote:
> Op woensdag 4 april 2012 01:26:14 UTC+2 schreef Frank Krygowski het volgende:
>> Lou Holtman wrote:
>>> Op 3-4-2012 4:34, Frank Krygowski schreef:
>>>>
>>>> BTW, I doubt that too much contact pressure would increase the chances
>>>> of slippage, unless something really weird was happening with your
>>>> bearings. The situation is similar to aquaplaning, I think, and I think
>>>> it's pretty well documented that greater load reduces aquaplaning
>>>> tendency.
>>>>
>>>
>>> We have the solution for all these problems from the past around here.
>>> All medium priced bikes and up have this solution fitted standard.
>>>
>>> Lou, bottle generators geezzz...
>>
>> Is that solution fitted to bikes designed for fast riding? I thought
>> the answer was no.
>
> We have no speed limits for bikes IIRC but you are correct that the bikes I was referring to are mostly used for commuting or other utility riding. On the other hand I can't imagine that on your side of the pond people are using the bikes with bottle generators for racing at 40 km/hr. I have two hub generators on two bikes which I use for 'fast' riding. There is no problem. The choice between a bottle generator, battery powered or a hub generator is a no brainer for me for any bike. Am I so different?
I use the same bike for commuting, casual riding, training and racing.
> Op woensdag 4 april 2012 01:26:14 UTC+2 schreef Frank Krygowski het volgende:
>> Lou Holtman wrote:
>>> Op 3-4-2012 4:34, Frank Krygowski schreef:
>>>>
>>>> BTW, I doubt that too much contact pressure would increase the chances
>>>> of slippage, unless something really weird was happening with your
>>>> bearings. The situation is similar to aquaplaning, I think, and I think
>>>> it's pretty well documented that greater load reduces aquaplaning
>>>> tendency.
>>>>
>>>
>>> We have the solution for all these problems from the past around here.
>>> All medium priced bikes and up have this solution fitted standard.
>>>
>>> Lou, bottle generators geezzz...
>>
>> Is that solution fitted to bikes designed for fast riding? I thought
>> the answer was no.
>
> We have no speed limits for bikes IIRC but you are correct that the bikes I was referring to are mostly used for commuting or other utility riding. On the other hand I can't imagine that on your side of the pond people are using the bikes with bottle generators for racing at 40 km/hr. I have two hub generators on two bikes which I use for 'fast' riding. There is no problem. The choice between a bottle generator, battery powered or a hub generator is a no brainer for me for any bike. Am I so different?
It takes a couple of minutes at most to remove the dynamo and light for
a race.
>> I've got hub dynamos on two bikes. They're very nice, and never slip.
>> But there certainly are disadvantages that go with the advantages - as
>> with almost everything else.
>
>
> Beside cost what are the disadvantages compared to a slipping bottle generator? The extra cost are neglectible when fitted from factory. That is what we learned to understand here.
--
JS.
Radey Shouman
Apr 4, 2012, 5:38:35 PM4/4/12
to
electronics at all, just magnets and coils. The bearings probably
wouldn't like drowning ...
--
James
Apr 4, 2012, 5:44:53 PM4/4/12
to
On 05/04/12 01:46, Jay Beattie wrote:
> As for dynamos, I like the idea of them, but now that it is getting
> light at night, it's not anything I need to buy. In fact, I'll be
> going to lighter equipment in preparation for commuter racing.
You know, if you can save a few grams ... ;-)
> As for dynamos, I like the idea of them, but now that it is getting
> light at night, it's not anything I need to buy. In fact, I'll be
> going to lighter equipment in preparation for commuter racing.
--
JS.
James
Apr 4, 2012, 5:58:01 PM4/4/12
to
On 05/04/12 07:14, Peter Cole wrote:
> What was the beam angle of your home brews?
With 4 CREE LEDs to focus, I used 3x 10 degree collimator lenses and 1x
> What was the beam angle of your home brews?
25 degree lens.
--
JS.
James
Apr 4, 2012, 6:30:12 PM4/4/12
to
On 03/04/12 21:56, Stephen Bauman wrote:
> On Tue, 03 Apr 2012 08:29:07 +1000, James wrote:
>
>> I've never noticed my Sanyo Dynapower roller dynamo slip in wet weather.
>> AFAIK, the light is always on while the dynamo is on the tyre and the
>> wheels are turning at a little faster than walking pace.
>>
>
> <snip>
>
> I experienced significant slippage in wet weather to the point that I
> replaced it with the Soubitez equivalent. The Sanyo had a very light
> spring whereas the Soubitez' was much stronger.
>
> Sanyo's light spring also meant it would bounce off the tire whenever I
> went over bumps. Sometimes the bounce was so great that it would snap
> back and engage the stop. Like others, I cured this by using rubber bands
> to get more pressure against the tire.
>
> On Tue, 03 Apr 2012 08:29:07 +1000, James wrote:
>
>> I've never noticed my Sanyo Dynapower roller dynamo slip in wet weather.
>> AFAIK, the light is always on while the dynamo is on the tyre and the
>> wheels are turning at a little faster than walking pace.
>>
>
> <snip>
>
> I experienced significant slippage in wet weather to the point that I
> replaced it with the Soubitez equivalent. The Sanyo had a very light
> spring whereas the Soubitez' was much stronger.
>
> Sanyo's light spring also meant it would bounce off the tire whenever I
> went over bumps. Sometimes the bounce was so great that it would snap
> back and engage the stop. Like others, I cured this by using rubber bands
> to get more pressure against the tire.
>
> Sanyo has upgraded its classic Dynapower bottom bracket generator with
> the NH-T10 model.
>
> http://www.peterwhitecycles.com/sanyo.asp
>
> the NH-T10 model.
>
> http://www.peterwhitecycles.com/sanyo.asp
>
> I installed one, along with modern LED lights. The dynamo appears to
> eliminate all the problems with the old model. There is a rubber covering
> for the roller wheel that eliminates slippage and the spring is much
> stronger. Also, the LED lights come to full brightness at only 1 watt so
> there much less effort is required. This also reduces slippage.
I had another thought. Incandescent bulbs have low resistance until the
> eliminate all the problems with the old model. There is a rubber covering
> for the roller wheel that eliminates slippage and the spring is much
> stronger. Also, the LED lights come to full brightness at only 1 watt so
> there much less effort is required. This also reduces slippage.
filament is hot. This would be like a short circuit on the dynamo
initially, and would cause much increased turning torque.
LED lights, OTOH, only start drawing current when the voltage has
increased to a level that causes them to turn on. This would allow the
dynamo to turn easier at slower speeds, and would lessen the tendency to
slip.
--
JS.
Stephen Bauman
Apr 4, 2012, 9:41:09 PM4/4/12
to
On Wed, 04 Apr 2012 12:14:23 -0400, Frank Krygowski wrote:
>
>
> I admire B&M's optics. They've done a good job. Their optical
> efficiency is hard to duplicate using the tools in my basement!
>
> Regarding electronics: I'm an ME (retired) so not as competent as you
> with electronics. But I'm curious about the specifics of the
> electronics in those lights. My curiosity comes from the fact that the
> critical parameter for an LED is current, and bike generators are
> essentially constant current devices, 0.5 Amp. Obviously, there's need
> for rectification, and for a capacitor if you want a standlight. But
> what else are B&M doing in there?
>
I'm also a pensioner.
>
>
> I admire B&M's optics. They've done a good job. Their optical
> efficiency is hard to duplicate using the tools in my basement!
>
> Regarding electronics: I'm an ME (retired) so not as competent as you
> with electronics. But I'm curious about the specifics of the
> electronics in those lights. My curiosity comes from the fact that the
> critical parameter for an LED is current, and bike generators are
> essentially constant current devices, 0.5 Amp. Obviously, there's need
> for rectification, and for a capacitor if you want a standlight. But
> what else are B&M doing in there?
>
It's difficult to talk about voltage and current sources because there's
a Duality Principle in circuitry. There are Thevenin and Norton
equivalent circuits (one a voltage source with a series impedance the
other a current source with a parallel impedance) that are
indistinguishable from their terminal characteristics.
The dynamo model that I'm familiar with is a variable AC voltage source
with a large inductor in series. The voltage source varies in magnitude
and frequency with the dynamo's rotational speed. The rationale for the
high series inductance was to keep the voltage across the incandescent
relatively constant for large variations in dynamo output.
Electronics can provide much better regulation. There's a lot to play
with because the dynamo's open circuit (no load attached) is quite high.
I've measured a bottle generator putting out 30 vac and very low speed.
The homebrew circuits I've seen will put out higher voltage at low speed
and hold that voltage nearly constant over a wider speed than the simple
series inductor.
> It seems many home brewers (like James) are doing fine just with
> rectification, or just using multiple LEDs to handle the different
> phases of the AC waveform. So what else is needed?
have also tailored their regulator to match the LED's performance. The
B&M light comes up to nearly peak brightness on just walking the bike. My
guess is that they are using a super cap to enhance low speed performance
and possibly another one for a standlight. There's also a design criteria
to convert every bit of pedal power into lumens.
Multiple LED designs that implement half wave rectifiers are not
conducting or emitting light 50% of the time. That's not an efficient use
of a fairly expensive component - the LED.
One other factor goes into B&M's design besides regulation and optics.
It's the heat sink for the LED. It influences not only the LED's life but
also it's light output. Given these three factors, plus a desired
production run of 1 unit, I decided it wasn't worth my time to try to
build a better mouse trap.
Stephen Bauman
Stephen Bauman
Apr 4, 2012, 9:59:45 PM4/4/12
to
On Thu, 05 Apr 2012 08:30:12 +1000, James wrote:
>
> I had another thought. Incandescent bulbs have low resistance until the
> filament is hot. This would be like a short circuit on the dynamo
> initially, and would cause much increased turning torque.
>
> LED lights, OTOH, only start drawing current when the voltage has
> increased to a level that causes them to turn on. This would allow the
> dynamo to turn easier at slower speeds, and would lessen the tendency to
> slip.
Higher startup drag due to low filament resistance would not explain why
>
> I had another thought. Incandescent bulbs have low resistance until the
> filament is hot. This would be like a short circuit on the dynamo
> initially, and would cause much increased turning torque.
>
> LED lights, OTOH, only start drawing current when the voltage has
> increased to a level that causes them to turn on. This would allow the
> dynamo to turn easier at slower speeds, and would lessen the tendency to
> slip.
the original Dynapower dynamo would slip after it had been on for a
relatively long time.
We used rubber caps for the bottle dynamos when it rained to reduce
slipping. The problem with the bottom bracket dynamos is that they did
not have any such caps. The NH-T10 has the equivalent of a rubber cap. I
think that is a more important factor as to why it does not slip.
Stephen Bauman
James
Apr 5, 2012, 1:39:02 AM4/5/12
to
On 05/04/12 11:41, Stephen Bauman wrote:
> Multiple LED designs that implement half wave rectifiers are not
> conducting or emitting light 50% of the time. That's not an efficient use
> of a fairly expensive component - the LED.
Mine has a pair of LEDs conducting for the positive half cycle, and
> Multiple LED designs that implement half wave rectifiers are not
> conducting or emitting light 50% of the time. That's not an efficient use
> of a fairly expensive component - the LED.
another pair of LEDs conducting during the negative half cycle. That is
all as far as electronics is required.
Yes, multiple relatively expensive parts and the need for multiple
optical elements, but very simple, robust and efficient. In fact, can
you identify where power is wasted?
OTOH, most switch mode LED drivers can achieve 90% efficiency - see here
for example http://www.diodes.com/_files/design_note_pdfs/zetex/dn85.pdf
One relatively expensive LED and optics with one current regulator,
etc., is better for B&M. They can further complicate the design with
stand lights at relatively low additional cost.
> One other factor goes into B&M's design besides regulation and optics.
> It's the heat sink for the LED. It influences not only the LED's life but
> also it's light output. Given these three factors, plus a desired
> production run of 1 unit, I decided it wasn't worth my time to try to
> build a better mouse trap.
bracket. Cost? I dunno, it was in my bin of offcuts.
All up cost was possibly $50.
Mine has no electromechanical switches or parts that must be protected
from moisture or dirt. In fact the LEDs have zero protection, aside
from the lens glued on to the front of them.
It has been through rain, dirty water, and down hills as fast as my
53x11 will allow. After 1 year of operation, it shows no signs of
weakness or degradation.
--
JS.
James
Apr 5, 2012, 1:45:55 AM4/5/12
to
On 05/04/12 11:59, Stephen Bauman wrote:
> On Thu, 05 Apr 2012 08:30:12 +1000, James wrote:
>
>
>>
>> I had another thought. Incandescent bulbs have low resistance until the
>> filament is hot. This would be like a short circuit on the dynamo
>> initially, and would cause much increased turning torque.
>>
>> LED lights, OTOH, only start drawing current when the voltage has
>> increased to a level that causes them to turn on. This would allow the
>> dynamo to turn easier at slower speeds, and would lessen the tendency to
>> slip.
>
> Higher startup drag due to low filament resistance would not explain why
> the original Dynapower dynamo would slip after it had been on for a
> relatively long time.
However, you hit a bump and it starts to slip, and the effort to
> On Thu, 05 Apr 2012 08:30:12 +1000, James wrote:
>
>
>>
>> I had another thought. Incandescent bulbs have low resistance until the
>> filament is hot. This would be like a short circuit on the dynamo
>> initially, and would cause much increased turning torque.
>>
>> LED lights, OTOH, only start drawing current when the voltage has
>> increased to a level that causes them to turn on. This would allow the
>> dynamo to turn easier at slower speeds, and would lessen the tendency to
>> slip.
>
> Higher startup drag due to low filament resistance would not explain why
> the original Dynapower dynamo would slip after it had been on for a
> relatively long time.
reignite the candle increases.
> We used rubber caps for the bottle dynamos when it rained to reduce
> slipping. The problem with the bottom bracket dynamos is that they did
> not have any such caps. The NH-T10 has the equivalent of a rubber cap. I
> think that is a more important factor as to why it does not slip.
Perhaps the grooves in the new dynapower rubber provide water channels
and additional contact pressure.
--
JS
Lou Holtman
Apr 5, 2012, 4:06:56 AM4/5/12
to
Op woensdag 4 april 2012 23:01:18 UTC+2 schreef Frank Krygowski het volgende:
> First, let me say I do think your situation is better than ours. Except
> for a very few and uncommon bikes, hub dynamos are not available as
> original equipment. So someone wanting a dynamo of any type will have
> to buy it as an aftermarket accessory.
I said we sorted things out here. 15 years ago most of the bikes over here had bottle dynamo's too. They were and are a PIA and now we switched to dynohubs which got a boost when good LED lighting came available. No one want to go back to bottle dynamo's. That is crap from the past.
> I do really like the hub units I have. But overall, it's obvious that
> there must be _some_ disadvantages to hub dynamos, or they wouldn't
> still sell bottle and roller units!
I don't think so. It is ignorance, cheapness and stubborness if you ask me.
Lou
> Lou Holtman wrote:
> > Op woensdag 4 april 2012 01:26:14 UTC+2 schreef Frank Krygowski het volgende:
> >>> All medium priced bikes and up have this solution fitted standard.
> >>> Lou, bottle generators geezzz...
> >>
> >> Is that solution fitted to bikes designed for fast riding? I thought
> >> the answer was no.
> >
> > We have no speed limits for bikes IIRC but you are correct that the bikes I was referring to are mostly used for commuting or other utility riding. On the other hand I can't imagine that on your side of the pond people are using the bikes with bottle generators for racing at 40 km/hr. I have two hub generators on two bikes which I use for 'fast' riding. There is no problem. The choice between a bottle generator, battery powered or a hub generator is a no brainer for me for any bike. Am I so different?
>
> OK. All of the heavier bikes, then, but not the lighter,
> performance-oriented bikes. (The rule is based on weight, isn't it?)
What do you mean by that? You fit a bottle dynamo on a performance oriented bike? The weight penalty for a hub dyno is about 200-300 gr for any bike compared to a regular front hub and is the same if you combine that hub with a bottle dynamo.
> > Op woensdag 4 april 2012 01:26:14 UTC+2 schreef Frank Krygowski het volgende:
> >>> All medium priced bikes and up have this solution fitted standard.
> >>> Lou, bottle generators geezzz...
> >>
> >> Is that solution fitted to bikes designed for fast riding? I thought
> >> the answer was no.
> >
> > We have no speed limits for bikes IIRC but you are correct that the bikes I was referring to are mostly used for commuting or other utility riding. On the other hand I can't imagine that on your side of the pond people are using the bikes with bottle generators for racing at 40 km/hr. I have two hub generators on two bikes which I use for 'fast' riding. There is no problem. The choice between a bottle generator, battery powered or a hub generator is a no brainer for me for any bike. Am I so different?
>
> OK. All of the heavier bikes, then, but not the lighter,
> performance-oriented bikes. (The rule is based on weight, isn't it?)
> First, let me say I do think your situation is better than ours. Except
> for a very few and uncommon bikes, hub dynamos are not available as
> original equipment. So someone wanting a dynamo of any type will have
> to buy it as an aftermarket accessory.
> I do really like the hub units I have. But overall, it's obvious that
> there must be _some_ disadvantages to hub dynamos, or they wouldn't
> still sell bottle and roller units!
Lou
David Scheidt
Apr 5, 2012, 9:49:26 AM4/5/12
to
James <james.e...@gmail.com> wrote:
:Is wet rubber on wet rubber any better than wet rubber on wet knurled metal?
By a factor of three or four, as I recall. That's why et railroad,
drains, and steel hole-covering plates are so dangerous o a bike.
--
sig 110
:Is wet rubber on wet rubber any better than wet rubber on wet knurled metal?
By a factor of three or four, as I recall. That's why et railroad,
drains, and steel hole-covering plates are so dangerous o a bike.
--
sig 110
Frank Krygowski
Apr 5, 2012, 11:21:07 AM4/5/12
to
Lou Holtman wrote:
> Op woensdag 4 april 2012 23:01:18 UTC+2 schreef Frank Krygowski het volgende:
>> Lou Holtman wrote:
>>> Op woensdag 4 april 2012 01:26:14 UTC+2 schreef Frank Krygowski het volgende:
>>>>> All medium priced bikes and up have this solution fitted standard.
>>>>> Lou, bottle generators geezzz...
>>>>
>>>> Is that solution fitted to bikes designed for fast riding? I thought
>>>> the answer was no.
>>>
>>> We have no speed limits for bikes IIRC but you are correct that the bikes I was referring to are mostly used for commuting or other utility riding. On the other hand I can't imagine that on your side of the pond people are using the bikes with bottle generators for racing at 40 km/hr. I have two hub generators on two bikes which I use for 'fast' riding. There is no problem. The choice between a bottle generator, battery powered or a hub generator is a no brainer for me for any bike. Am I so different?
>>
>> OK. All of the heavier bikes, then, but not the lighter,
>> performance-oriented bikes. (The rule is based on weight, isn't it?)
>
> What do you mean by that? You fit a bottle dynamo on a performance oriented bike? The weight penalty for a hub dyno is about 200-300 gr for any bike compared to a regular front hub and is the same if you combine that hub with a bottle dynamo.
What I meant was this: It's my understanding that at least in some
> Op woensdag 4 april 2012 23:01:18 UTC+2 schreef Frank Krygowski het volgende:
>> Lou Holtman wrote:
>>> Op woensdag 4 april 2012 01:26:14 UTC+2 schreef Frank Krygowski het volgende:
>>>>> All medium priced bikes and up have this solution fitted standard.
>>>>> Lou, bottle generators geezzz...
>>>>
>>>> Is that solution fitted to bikes designed for fast riding? I thought
>>>> the answer was no.
>>>
>>> We have no speed limits for bikes IIRC but you are correct that the bikes I was referring to are mostly used for commuting or other utility riding. On the other hand I can't imagine that on your side of the pond people are using the bikes with bottle generators for racing at 40 km/hr. I have two hub generators on two bikes which I use for 'fast' riding. There is no problem. The choice between a bottle generator, battery powered or a hub generator is a no brainer for me for any bike. Am I so different?
>>
>> OK. All of the heavier bikes, then, but not the lighter,
>> performance-oriented bikes. (The rule is based on weight, isn't it?)
>
> What do you mean by that? You fit a bottle dynamo on a performance oriented bike? The weight penalty for a hub dyno is about 200-300 gr for any bike compared to a regular front hub and is the same if you combine that hub with a bottle dynamo.
European countries, any bike weighing more than - what? maybe 10 kg? -
must be sold with a dynamo installed. Bikes weighing less are exempt.
Is that not the case? (If I've got that weight limit wrong, let us know
what the correct value is.)
>> First, let me say I do think your situation is better than ours. Except
>> for a very few and uncommon bikes, hub dynamos are not available as
>> original equipment. So someone wanting a dynamo of any type will have
>> to buy it as an aftermarket accessory.
>
> I said we sorted things out here. 15 years ago most of the bikes over here had bottle dynamo's too. They were and are a PIA and now we switched to dynohubs which got a boost when good LED lighting came available. No one want to go back to bottle dynamo's. That is crap from the past.
quite different. Hub dynamos, or dynamos of any variety, are not
standard. In fact, headlights of any kind are rather rare.
>> I do really like the hub units I have. But overall, it's obvious that
>> there must be _some_ disadvantages to hub dynamos, or they wouldn't
>> still sell bottle and roller units!
>
> I don't think so. It is ignorance, cheapness and stubborness if you ask me.
to portray it as stupid. But deeper thinking sometimes gives better
insight.
--
- Frank Krygowski
Frank Krygowski
Apr 5, 2012, 11:45:54 AM4/5/12
to
I've moved LEDs from lamp to lamp. I had some high powered LEDs plus
optics given to me by a friend working in the field, and I also tried
some different optics with them.
One optic I tried was recommended by Chalo, an elliptical one from Deal
Extreme. I'm thinking perhaps 5 degrees vertical, perhaps 15 or 20
horizontal. Far too little throw for my purposes. That one barely made
it out of my basement.
I put more riding time on some sort of spot optic (maybe fifteen
degrees?), and spent some time experimenting with slight changes in the
relationship of the LED to the lens, hoping to shape the beam a bit
better for road use. It was somewhat more conspicuous than a standard
halogen headlight but it lit the road not nearly as well.
Part of my problem was that I was playing with donated LEDs, and some
donated lenses. Most of them were not a particularly good match either
to each other, or to the demands of the road.
About that time, my wife gave me the Cyo IQ for Christmas, which was ten
times better than what I'd come up with, so I stopped playing with them
for a while.
Then I built up a retro 3 speed with a retro Sturmey-Archer Dynohub and
the original matching headlamp, a metal thing nearly the size of a
softball. I reclaimed an LED and put it into that big lamp. On the
plus side, the huge size of the lamp gave more possibilities for playing
with beam shape. On the negative side, the SA headlamp lens was
essentially a small double-convex spot in the center of a plain lens,
sort of projecting an image of the original filament (or now, the LED)
down the road. The lamp also allows for fore-aft adjustment of the
filament or LED. Originally, IIRC, I got one bright spot in a dark
field, not very useful. My latest version of that has a fogged piece of
clear plastic hung in front of the LED, and a tiny aluminum shield as an
"eyebrow" above and in front of the LED, to direct light downward
instead of into the tree branches. That's working pretty well, although
it's used just for neighborhood cruising.
--
- Frank Krygowski
Frank Krygowski
Apr 5, 2012, 12:00:11 PM4/5/12
to
values in my life! I find I can putter quite happily with things that
have very little value, beyond satisfying my curiosity!
But I understand. The acquisition of a Cyo did stop some of my experiments.
Anyway, it's true that one can measure 30 V out of a dynamo; but that's
open circuit. To me, the easiest way to understand these things is that
they put out a constant half Amp, or thereabouts. Give them a low
resistance load and the voltage necessary for that 0.5 A is very low.
Give them a high resistance load (or the extreme, an open circuit) and
they try their mightiest to pump half an Amp - that is, they produce
high voltage.
But it matters not to an LED. The LED has effectively low resistance,
and most high brightness ones seem designed for about 0.7 A. They work
nearly as well at 0.5 A, which is what the dynamo will deliver.
Perhaps, as you say, B&M is trying to get every last bit of efficiency.
And the possibility of using a capacitor to help very low speed output
is interesting. But I'd certainly like to see a circuit diagram. (And a
simple explanation, as a non-EE.)
--
- Frank Krygowski
Lou Holtman
Apr 5, 2012, 12:54:01 PM4/5/12
to
Op 5-4-2012 17:21, Frank Krygowski schreef:
advantages of a bottle generator compared to a hubgenerator right?.
Really Frank, if you want to generate power you have to turn something
and guess what, the front hub turns already. How hard is it to
understand that that is an order of a magnitude better than spring load
a wheel against an undefined rubber surface?
Lou
> Lou Holtman wrote:
>
>>> I do really like the hub units I have. But overall, it's obvious that
>>> there must be _some_ disadvantages to hub dynamos, or they wouldn't
>>> still sell bottle and roller units!
>>
>> I don't think so. It is ignorance, cheapness and stubborness if you
>> ask me.
>
> Well, if you disagree with another person's decision, it may seem simple
> to portray it as stupid. But deeper thinking sometimes gives better
> insight.
>
I didn't say stupid and I respect everyones choice but we are discussing
>
>>> I do really like the hub units I have. But overall, it's obvious that
>>> there must be _some_ disadvantages to hub dynamos, or they wouldn't
>>> still sell bottle and roller units!
>>
>> I don't think so. It is ignorance, cheapness and stubborness if you
>> ask me.
>
> Well, if you disagree with another person's decision, it may seem simple
> to portray it as stupid. But deeper thinking sometimes gives better
> insight.
>
advantages of a bottle generator compared to a hubgenerator right?.
Really Frank, if you want to generate power you have to turn something
and guess what, the front hub turns already. How hard is it to
understand that that is an order of a magnitude better than spring load
a wheel against an undefined rubber surface?
Lou
Frank Krygowski
Apr 5, 2012, 6:43:08 PM4/5/12
to
Lou Holtman wrote:
> Op 5-4-2012 17:21, Frank Krygowski schreef:
>> Lou Holtman wrote:
>
>>
>>>> I do really like the hub units I have. But overall, it's obvious that
>>>> there must be _some_ disadvantages to hub dynamos, or they wouldn't
>>>> still sell bottle and roller units!
>>>
>>> I don't think so. It is ignorance, cheapness and stubborness if you
>>> ask me.
>>
>> Well, if you disagree with another person's decision, it may seem simple
>> to portray it as stupid. But deeper thinking sometimes gives better
>> insight.
>>
>
> I didn't say stupid...
> Op 5-4-2012 17:21, Frank Krygowski schreef:
>> Lou Holtman wrote:
>
>>
>>>> I do really like the hub units I have. But overall, it's obvious that
>>>> there must be _some_ disadvantages to hub dynamos, or they wouldn't
>>>> still sell bottle and roller units!
>>>
>>> I don't think so. It is ignorance, cheapness and stubborness if you
>>> ask me.
>>
>> Well, if you disagree with another person's decision, it may seem simple
>> to portray it as stupid. But deeper thinking sometimes gives better
>> insight.
>>
>
True. Substitute "ignorant, cheap, stubborn" if you prefer.
> and I respect everyones choice but we are discussing
> advantages of a bottle generator compared to a hubgenerator right?.
> Really Frank, if you want to generate power you have to turn something
> and guess what, the front hub turns already. How hard is it to
> understand that that is an order of a magnitude better than spring load
> a wheel against an undefined rubber surface?
--
- Frank Krygowski
datakoll
Apr 5, 2012, 9:32:31 PM4/5/12
to
datakoll
Apr 5, 2012, 10:00:47 PM4/5/12
to
FROST COVERED STEEL BRIDGE GRATES.....terminello !
drove from Grand Canyon to Capitol Reef all night listening to excellent play from XM (why the chnage ?), nice roads, patter pattter patter tar seamed swoop swoop
and at the bottom of THE GRADE...state had hung out the ICE ON ROAD sign.....uh what ice ice ? so I slammed on the ABS brakes and
BEHOLD
skiddedacross the road
Toyo A/T
Dan O
Apr 6, 2012, 12:49:51 AM4/6/12
to
On Apr 5, 8:21 am, Frank Krygowski <frkrygowREM...@gEEmail.com> wrote:
<snip>
>
> Well, if you disagree with another person's decision, it may seem simple
> to portray it as stupid. But deeper thinking sometimes gives better
> insight.
>
Print this out and tape it to your monitor. (Try to exercise your
brain laterally, as well.)
<snip>
>
> Well, if you disagree with another person's decision, it may seem simple
> to portray it as stupid. But deeper thinking sometimes gives better
> insight.
>
brain laterally, as well.)
Kerry Montgomery
Apr 6, 2012, 2:17:25 AM4/6/12
to
"Dan O" <danov...@gmail.com> wrote in message
news:17c28cbc-615e-4b94...@a8g2000pbe.googlegroups.com...
I did as you suggested, but can no longer see all of the stuff I used to be
able to on my screen!
Kerry
Message has been deleted
Dan O
Apr 6, 2012, 3:01:38 AM4/6/12
to
On Apr 5, 11:38 pm, davethedave <davedfoster...@gmail.com> wrote:
>
My Slackware gateway runs on a headless IBM Intellistation 6899 (200
MHz PPro). I love telling the kids that not only do you not need a
mouse to operate a computer, you can do it without a monitor (just
input and listen for the expected feedback from the SCSI fixed
disk :-)
> On Thu, 05 Apr 2012 23:17:25 -0700, Kerry Montgomery wrote:
> >> <snip>
>
> >>> Well, if you disagree with another person's decision, it may seem
> >>> simple to portray it as stupid. But deeper thinking sometimes gives
> >>> better insight.
>
> >> Print this out and tape it to your monitor. (Try to exercise your
> >> brain laterally, as well.)
>
> > Dan O,
> > I did as you suggested, but can no longer see all of the stuff I used to
> > be able to on my screen!
> > Kerry
>
> Heh. :)
> >> <snip>
>
> >>> Well, if you disagree with another person's decision, it may seem
> >>> simple to portray it as stupid. But deeper thinking sometimes gives
> >>> better insight.
>
> >> Print this out and tape it to your monitor. (Try to exercise your
> >> brain laterally, as well.)
>
> > Dan O,
> > I did as you suggested, but can no longer see all of the stuff I used to
> > be able to on my screen!
> > Kerry
>
>
My Slackware gateway runs on a headless IBM Intellistation 6899 (200
MHz PPro). I love telling the kids that not only do you not need a
mouse to operate a computer, you can do it without a monitor (just
input and listen for the expected feedback from the SCSI fixed
disk :-)
sms88
Apr 6, 2012, 9:38:49 PM4/6/12
to
On 4/5/2012 1:06 AM, Lou Holtman wrote:
> I don't think so. It is ignorance, cheapness and stubborness if you ask me.
It's cost and convenience. One model of bottle dynamo fits most bikes.
> I don't think so. It is ignorance, cheapness and stubborness if you ask me.
For hubs you need to choose based on the spoke count, based on the
dropout width, and based on the wheel diameter. You don't want to use a
dynamo designed for 16" wheels on a 29er (or vice versa), though by the
same token you could say that a bottle dynamo has the same issue.
The bottom bracket dynamos were fine in the days of steel frames, but
not so good anymore.
Bicycle manufacturers are loath to add cost to every unit for a feature
that few people care about, so you're not going to see hub dynamos as
standard equipment on anything other than hard-core commute bikes. I
could probably count on one hand the number of brands sold in the U.S.
that come standard with a hub dynamo, and even then it's a small number
of models from each brand. Novara, Tern, Breezer, Kettler, Nirve, and
those last two are very rare.
To add a dynamo hub to an existing bicycle can be an expensive
proposition. I've done it, and you're looking at at least $100 for a new
wheel with a cheap dynamo hub. It's too bad because the cost to the
bicycle manufacturer for a dynamo hub is not very much.
Even with a hub dynamo, you end up with lights that are not nearly as
good as battery powered lights in terms of illumination, though at least
you don't have to deal with batteries and recharging.
Sepp Ruf
Apr 7, 2012, 2:16:25 AM4/7/12
to
Stephen Bauman wrote:
> B&M light comes up to nearly peak brightness on just walking the bike.
More probably, "peak correlated color temperature." Your measurements
> B&M light comes up to nearly peak brightness on just walking the bike.
were performed by solely using Eyes 1.0, I presume?
Stephen Bauman
Apr 9, 2012, 7:18:18 PM4/9/12
to
However, my brightness observation was based on what the light
illuminated while I was walking the bike.
The slow speed shortcoming of dynamo powered incandescent lights has been
eliminated. You can be crawling up a mountain at 3 mph and still see
where you are going. There's no need to jump out of the saddle to push
the dynamo for one downstroke to see where you are going. There's a
steady light that is probably better than the old incandescents when
traveling at 12 mph.
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