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Better Braking?



 
 
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  #301  
Old February 18th 20, 04:17 PM posted to rec.bicycles.tech
SMS
external usenet poster
 
Posts: 9,477
Default Better Braking?

On 2/18/2020 6:25 AM, Sepp Ruf wrote:

snip

And don't forget wasteful springs moving in the generator mount because the
wheel is not perfectly trued. But wait, that's still top secret, we at
SpringShine Corp. (Shenzen, Denmark) will be exploiting this effect to
introduce WheelPulseLED®, the next big crowdfunded "lossless" project in
bicycle lighting.


I think that as panel trucks knock down low hanging branches they should
also be charging batteries that are embedded into the trees and that
drive inductive chargers that cyclists can ride next to to charge their
battery powered lights. Very similar to inductive charging being used
for mobile phones.


Ads
  #302  
Old February 18th 20, 04:38 PM posted to rec.bicycles.tech
Andre Jute[_2_]
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Posts: 10,422
Default Better Braking?

On Tuesday, February 18, 2020 at 9:32:31 AM UTC+1, John B. wrote:

Of course there is a power loss but it is not the friction between the
generator roller and the tire wall.


You're dumber, Slow Johnny, than you accuse Tom of being. And you're very persistently dumb, too. It must be habit forming, or in your genes.

Wear this smart pointed cap and write one hundred times on the blackboard:
ANY TIME ONE WHEEL DRIVES ANOTHER BY FRICTION BETWEEN THEM, POWER IS LOST

Andre Jute
We can only hope you didn't breed any road kill
  #303  
Old February 18th 20, 04:52 PM posted to rec.bicycles.tech
Andre Jute[_2_]
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Posts: 10,422
Default Better Braking?

On Tuesday, February 18, 2020 at 3:17:24 PM UTC, sms wrote:
On 2/18/2020 6:25 AM, Sepp Ruf wrote:

snip

And don't forget wasteful springs moving in the generator mount because the
wheel is not perfectly trued. But wait, that's still top secret, we at
SpringShine Corp. (Shenzen, Denmark) will be exploiting this effect to
introduce WheelPulseLED®, the next big crowdfunded "lossless" project in
bicycle lighting.


I think that as panel trucks knock down low hanging branches they should
also be charging batteries that are embedded into the trees and that
drive inductive chargers that cyclists can ride next to to charge their
battery powered lights. Very similar to inductive charging being used
for mobile phones.


Where I live, even the bigger SUVs can knock down branches, as can cyclists who sit upright on properly-sized bikes.

I'll tell you something else: before Kreepy Krygo even starts screeching that he knows better than the people who live here how low the branches sweep over the road, the Council and the environmentalists make matters worse. The Council has a regulation, made under the influence of the Greenies, that the hedges should not be cut before September 30th, and to avoid trouble is inclined to view trees beside the road as "hedge". And the environmentalists, if they see a mobile hedge trimmer or Council tree surgeon truck in the lanes before the end of October, are instantly on the phone to the Council and their Member of Parliament to complain to high heaven that the Council is ruining the countryside -- again.

Andre Jute
Who would be foolish enough to run for election to any post where the environmentalists can complain about what he does or doesn't do?
  #304  
Old February 18th 20, 05:08 PM posted to rec.bicycles.tech
Ralph Barone[_4_]
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Posts: 853
Default Better Braking?

John B. wrote:
On Tue, 18 Feb 2020 04:48:17 +0000 (UTC), Ralph Barone
wrote:

John B. wrote:
On Mon, 17 Feb 2020 06:17:01 -0800 (PST), Tom Kunich
wrote:

On Saturday, February 15, 2020 at 6:50:46 AM UTC-8, AMuzi wrote:
On 2/14/2020 10:18 PM, Frank Krygowski wrote:
On Friday, February 14, 2020 at 6:34:47 PM UTC-5, AMuzi wrote:
On 2/14/2020 5:05 PM, Frank Krygowski wrote:
On 2/14/2020 5:47 PM, John B. wrote:
On Fri, 14 Feb 2020 21:35:18 -0000 (UTC), Duane
wrote:

jbeattie wrote:
On Friday, February 14, 2020 at 11:35:46 AM UTC-8, Duane
wrote:
On 2/14/2020 2:23 PM, Sir Ridesalot wrote:
On Friday, 14 February 2020 12:00:11 UTC-5, Frank
Krygowski wrote:
On 2/13/2020 5:47 PM, Tom Kunich wrote:
On Thursday, February 13, 2020 at 2:36:58 PM UTC-8,
John B. Slocomb wrote:

Own Data? You mean like your assertions that a
cheap Chinese
flashlight is a perfect bicycle head light? ...

I have taken Steven's word at the effectiveness of
"cheap Chinese
flashlights as bicycle lights" and he was completely
correct. Sorry
if you seem to think that you know anything about
anything but you
have shown yourself to be a great deal heavier on
opinion than knowledge of anything.

You say Mr. Scharf was completely correct when he
touted cheap Chinese
flashlights as bike headlights. That was when he said
dyno powered
headlights were terrible and foolish.

Problem is, Mr. Scharf is now using dyno powered
headlights on his
bikes, and no longer seems to say cheap Chinese
flashlights are perfect.

My first question is, was he completely correct back
then? Or is he
completely correct now?

My second question regards specific details. My dyno
powered LED
headlights illuminate the entire width of the lane,
and simultaneously
illuminate stop signs up to a quarter mile away from
me, all without
blinding oncoming riders.

The Chinese flashlight I tried could not do that, no
matter how I
adjusted the tilt and the focus. It was a truly
crappy headlight. What,
specifically, does yours do? What's its brand and model?



--
- Frank Krygowski

Some people use flashlights that have a narrow beam
but good range.
Those lights might be okay as a be seen light but they
don't light up
much of the road. Others use flashlights with
adjustable focus that
spread the beams to light of more of the road. the
trouble is that when
they do that they lose the range they need if riding
in totally dark
conditions with no city lights.

I really like my CygoLite Rover II light as it does
light up the two
lanes of the country roads around here and it does so
no matter what
speed I'm riding at. Also, I can move the battery and
light unit from
bike to bike easily. I do wish it had a bit more
range. For that reason
I was considering getting the Centauri or Trident.
Dynamo lights simply
don't meet my needs.

Cheers


I imagine it depends on what you want. I use a Planet
Bike 2w when I'm
doing club rides in the evening because it's dark on my
ride back home
from the start. But I'm not out in the country, only
the burbs. I
don't need a lot of distance but I need something to
show me the
potholes in enough time to avoid them. My guess is
that a flashlight
would probably work in that case.

Then you have people riding in the rain, pitch dark,
pitch dark rain
down steep declines etc. etc. etc. I seriously doubt
that there's a one
for all solution.

In the latter circumstances, a dyno clearly is not the
solution. In
stormy weather, fast downhill or trail, a bright battery
light is best .
. . for me, and speaking as someone who owns a dyno and
battery lights. I
can A/B my dyno and my little all-in-on L&M Urban 800
every night since I
use both. The L&M produces far better light; it is one
fourth the total
price of my dyno set up and suffers only in that it
requires charging.

-- Jay Beattie.



Like I’ve said before most of times that I’m riding
at night it’s by
accident. The few planned times are as I described. So
a dyno doesn’t do
much for me.

Oddly, "riding at night by accident" is one of the main
reasons I settled on dyno lights. A big event for me was
being on a solo tour in Middle-Of-Nowhere Township, trying
to get to a particular state park. It was hillier than I
anticipated, dinner in a restaurant took extra long, and
surprise, I had to do the last few miles in the dark.

So I pulled out the battery light I'd brought and turned it
on. The batteries got me to, oh, 3 to 5 miles from the
campground. Then nothing. On a two lane country highway.

Fortunately, traffic was light. I finished by pulling way
off the side of the road whenever a car came. I then
installed a dyno on every bike.

Since then, there have been countless times I didn't plan on
riding in the dark, but had to - meetings that ran long,
extra work to get done, having too much fun to leave, etc.
It's no problem. My lights are just like those on my car. No
preparation needed, just turn them on and they work.

I can see that wouldn't be valuable for people who use their
bikes differently than I do.

As for charging, it’s pretty much routine. I have to
charge my phone, my
Garmin, my lights and even my watch. Pfft. Battery
charge is now an
issue. A Garmin and a phone that can last for a 175km
ride hS become a
thing.

Again, we all have different requirements. The fact that
we all ride bikes
is way cool. Too bad we can’t avoid the bull**** here.

and then a thread would look like:

Hey! I use a Gamnin!
-----
You do? So do I.
----
Wow! I use one too.
---
Doesn't everybody use a Garmin?
---
So cheap they ought to.
---
:-)

:-) And it would require so little technical thinking! Win
- win!



Well, someone could always very precisely measure some
aspect another guy cares nothing about and call it 'data'.

I don't think it's better to give no measurements, nothing but a
vague "mine is better" opinion, and say "data doesn't matter."

What do you use for lights? How well do they work for you? Why?

- Frank Krygowski


Exactly. You and I have chosen no-switch always-on dynamos
with which we are satisfied based on convenience and
dependability with virtually zero maintenance. Heated
discussions of amp hours, megalumens and optic patterns may
be vaguely interesting but not relevant to my (our?) cycling.

Regarding the topic, braking, ditto. No one disputes that
big fluid discs have better peak braking power and heat
dissipation for sustained braking power. One might chart
those factors impressively in comparison to rim brakes. For
the bike I ride this time of year, a simple sidepull front
with fixed gear is perfectly adequate and I've never wanted
for more braking power[1] on that bike given the way I use
it. I'm not Jay, nor Joerg, who have different needs and taste.

[1] what that bike really needs is a heater!
--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

I am quite aware that friction losses from a hub generator are minor but
that isn't so for a sidewall generator because it has to be pressed very
tightly against the sidewall to keep it was slipping. So it takes
probably two to three times the frictional losses as the light output.

Er... Tommy, frictional losses in mechanical devices is: " Friction
occurs when two bodies are in contact with each other and have
relative motion".

However you say " pressed very tightly against the sidewall to keep it
was slipping" and if there is no slipping than obviously there is no
relative motion and thus no friction.



Call it frictional losses or rolling resistance, but power is lost rolling
a bottle generator against a sidewall beyond that which a hub generator
would incur.


Of course there is a power loss but it is not the friction between the
generator roller and the tire wall.


No, but unless you are making a point of being pedantic (which seems to
happen a lot around here), you could say that the hysteresis losses in the
tire sidewalk that occur when it is deformed and then released are due to
friction like effects within the bulk of the rubber.


AND ONCE AGAIN THE INDOMONIBLE TOMMIE PROVES TO THE WORLD that he
doesn't know what he is talking about.


When Frank is telling us that he only lost on mph at a speed where he is
generating almost his entire output capacity my eyes are rolling and so must everyone's.

No Tommy, the eyes are rolling because you don't know what you are
talking about.
--
cheers,

John B.




--
cheers,

John B.





  #305  
Old February 18th 20, 08:00 PM posted to rec.bicycles.tech
Frank Krygowski[_4_]
external usenet poster
 
Posts: 10,538
Default Better Braking?

On 2/18/2020 11:08 AM, Ralph Barone wrote:
John B. wrote:
On Tue, 18 Feb 2020 04:48:17 +0000 (UTC), Ralph Barone
wrote:

John B. wrote:

However you say " pressed very tightly against the sidewall to keep it
was slipping" and if there is no slipping than obviously there is no
relative motion and thus no friction.


Call it frictional losses or rolling resistance, but power is lost rolling
a bottle generator against a sidewall beyond that which a hub generator
would incur.


Of course there is a power loss but it is not the friction between the
generator roller and the tire wall.


No, but unless you are making a point of being pedantic (which seems to
happen a lot around here), you could say that the hysteresis losses in the
tire sidewalk that occur when it is deformed and then released are due to
friction like effects within the bulk of the rubber.


It does get a bit complicated.

With a sidewall dynamo, the contact patch between the dyno and the tire
is fairly rectangular. (You can check that using carbon paper, if you
can still find some.) The tire's surface velocity at the largest radius
of that rectangle is greater than at the smallest radius of that
rectangle. If the roller is cylindrical (as on old Union dynos), there
has to be some scrubbing. (I have one obscure Japanese dyno with a
somewhat conical roller, and I wonder if that's the reason for its shape.)

As I've said before, on a couple bikes I've lathe-turned an O-ring
groove into the dyno roller and I run the O-ring on the braking surface
of the rim. This should minimize that source of friction, but I can't
say how much. It certainly makes the dyno quieter.

But the dyno I used in the event I described was a bottom bracket or
roller design, installed behind the crankset. The roller is larger than
that of a bottle dyno, so it sees less force; and it rotates in the same
plane as the tire. I've measured higher efficiency for those, compared
to bottle dynos. So have others in their lab tests.

But any time a rubber surface is used to drive rotation, some friction
loss must occur because of flexibility of the rubber, hysteresis losses,
and velocity differences like those above. Similarly, your bike's wheel
rotation speed is not computed precisely by V=r*omega. There's always
microscopic "slippage" due to the tire flexing. Tires also flex
laterally when asked to steer, so your front wheel doesn't go precisely
where it's pointed in a curve. This is true for cars as well as bikes.

There's no doubt a hub dyno has less loss than both the above designs.
I've got them on a couple of bikes, and will probably get more.


--
- Frank Krygowski
  #306  
Old February 18th 20, 11:53 PM posted to rec.bicycles.tech
jOHN b.
external usenet poster
 
Posts: 2,421
Default Better Braking?

On Tue, 18 Feb 2020 16:08:29 +0000 (UTC), Ralph Barone
wrote:

John B. wrote:
On Tue, 18 Feb 2020 04:48:17 +0000 (UTC), Ralph Barone
wrote:

John B. wrote:
On Mon, 17 Feb 2020 06:17:01 -0800 (PST), Tom Kunich
wrote:

On Saturday, February 15, 2020 at 6:50:46 AM UTC-8, AMuzi wrote:
On 2/14/2020 10:18 PM, Frank Krygowski wrote:
On Friday, February 14, 2020 at 6:34:47 PM UTC-5, AMuzi wrote:
On 2/14/2020 5:05 PM, Frank Krygowski wrote:
On 2/14/2020 5:47 PM, John B. wrote:
On Fri, 14 Feb 2020 21:35:18 -0000 (UTC), Duane
wrote:

jbeattie wrote:
On Friday, February 14, 2020 at 11:35:46 AM UTC-8, Duane
wrote:
On 2/14/2020 2:23 PM, Sir Ridesalot wrote:
On Friday, 14 February 2020 12:00:11 UTC-5, Frank
Krygowski wrote:
On 2/13/2020 5:47 PM, Tom Kunich wrote:
On Thursday, February 13, 2020 at 2:36:58 PM UTC-8,
John B. Slocomb wrote:

Own Data? You mean like your assertions that a
cheap Chinese
flashlight is a perfect bicycle head light? ...

I have taken Steven's word at the effectiveness of
"cheap Chinese
flashlights as bicycle lights" and he was completely
correct. Sorry
if you seem to think that you know anything about
anything but you
have shown yourself to be a great deal heavier on
opinion than knowledge of anything.

You say Mr. Scharf was completely correct when he
touted cheap Chinese
flashlights as bike headlights. That was when he said
dyno powered
headlights were terrible and foolish.

Problem is, Mr. Scharf is now using dyno powered
headlights on his
bikes, and no longer seems to say cheap Chinese
flashlights are perfect.

My first question is, was he completely correct back
then? Or is he
completely correct now?

My second question regards specific details. My dyno
powered LED
headlights illuminate the entire width of the lane,
and simultaneously
illuminate stop signs up to a quarter mile away from
me, all without
blinding oncoming riders.

The Chinese flashlight I tried could not do that, no
matter how I
adjusted the tilt and the focus. It was a truly
crappy headlight. What,
specifically, does yours do? What's its brand and model?



--
- Frank Krygowski

Some people use flashlights that have a narrow beam
but good range.
Those lights might be okay as a be seen light but they
don't light up
much of the road. Others use flashlights with
adjustable focus that
spread the beams to light of more of the road. the
trouble is that when
they do that they lose the range they need if riding
in totally dark
conditions with no city lights.

I really like my CygoLite Rover II light as it does
light up the two
lanes of the country roads around here and it does so
no matter what
speed I'm riding at. Also, I can move the battery and
light unit from
bike to bike easily. I do wish it had a bit more
range. For that reason
I was considering getting the Centauri or Trident.
Dynamo lights simply
don't meet my needs.

Cheers


I imagine it depends on what you want. I use a Planet
Bike 2w when I'm
doing club rides in the evening because it's dark on my
ride back home
from the start. But I'm not out in the country, only
the burbs. I
don't need a lot of distance but I need something to
show me the
potholes in enough time to avoid them. My guess is
that a flashlight
would probably work in that case.

Then you have people riding in the rain, pitch dark,
pitch dark rain
down steep declines etc. etc. etc. I seriously doubt
that there's a one
for all solution.

In the latter circumstances, a dyno clearly is not the
solution. In
stormy weather, fast downhill or trail, a bright battery
light is best .
. . for me, and speaking as someone who owns a dyno and
battery lights. I
can A/B my dyno and my little all-in-on L&M Urban 800
every night since I
use both. The L&M produces far better light; it is one
fourth the total
price of my dyno set up and suffers only in that it
requires charging.

-- Jay Beattie.



Like I’ve said before most of times that I’m riding
at night it’s by
accident. The few planned times are as I described. So
a dyno doesn’t do
much for me.

Oddly, "riding at night by accident" is one of the main
reasons I settled on dyno lights. A big event for me was
being on a solo tour in Middle-Of-Nowhere Township, trying
to get to a particular state park. It was hillier than I
anticipated, dinner in a restaurant took extra long, and
surprise, I had to do the last few miles in the dark.

So I pulled out the battery light I'd brought and turned it
on. The batteries got me to, oh, 3 to 5 miles from the
campground. Then nothing. On a two lane country highway.

Fortunately, traffic was light. I finished by pulling way
off the side of the road whenever a car came. I then
installed a dyno on every bike.

Since then, there have been countless times I didn't plan on
riding in the dark, but had to - meetings that ran long,
extra work to get done, having too much fun to leave, etc.
It's no problem. My lights are just like those on my car. No
preparation needed, just turn them on and they work.

I can see that wouldn't be valuable for people who use their
bikes differently than I do.

As for charging, it’s pretty much routine. I have to
charge my phone, my
Garmin, my lights and even my watch. Pfft. Battery
charge is now an
issue. A Garmin and a phone that can last for a 175km
ride hS become a
thing.

Again, we all have different requirements. The fact that
we all ride bikes
is way cool. Too bad we can’t avoid the bull**** here.

and then a thread would look like:

Hey! I use a Gamnin!
-----
You do? So do I.
----
Wow! I use one too.
---
Doesn't everybody use a Garmin?
---
So cheap they ought to.
---
:-)

:-) And it would require so little technical thinking! Win
- win!



Well, someone could always very precisely measure some
aspect another guy cares nothing about and call it 'data'.

I don't think it's better to give no measurements, nothing but a
vague "mine is better" opinion, and say "data doesn't matter."

What do you use for lights? How well do they work for you? Why?

- Frank Krygowski


Exactly. You and I have chosen no-switch always-on dynamos
with which we are satisfied based on convenience and
dependability with virtually zero maintenance. Heated
discussions of amp hours, megalumens and optic patterns may
be vaguely interesting but not relevant to my (our?) cycling.

Regarding the topic, braking, ditto. No one disputes that
big fluid discs have better peak braking power and heat
dissipation for sustained braking power. One might chart
those factors impressively in comparison to rim brakes. For
the bike I ride this time of year, a simple sidepull front
with fixed gear is perfectly adequate and I've never wanted
for more braking power[1] on that bike given the way I use
it. I'm not Jay, nor Joerg, who have different needs and taste.

[1] what that bike really needs is a heater!
--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

I am quite aware that friction losses from a hub generator are minor but
that isn't so for a sidewall generator because it has to be pressed very
tightly against the sidewall to keep it was slipping. So it takes
probably two to three times the frictional losses as the light output.

Er... Tommy, frictional losses in mechanical devices is: " Friction
occurs when two bodies are in contact with each other and have
relative motion".

However you say " pressed very tightly against the sidewall to keep it
was slipping" and if there is no slipping than obviously there is no
relative motion and thus no friction.


Call it frictional losses or rolling resistance, but power is lost rolling
a bottle generator against a sidewall beyond that which a hub generator
would incur.


Of course there is a power loss but it is not the friction between the
generator roller and the tire wall.


No, but unless you are making a point of being pedantic (which seems to
happen a lot around here), you could say that the hysteresis losses in the
tire sidewalk that occur when it is deformed and then released are due to
friction like effects within the bulk of the rubber.


I was replying to Tom who said, "because it has to be pressed very
tightly against the sidewall to keep it was slipping. So it takes
probably two to three times the frictional losses as the light
output."

That simply isn't true.



AND ONCE AGAIN THE INDOMONIBLE TOMMIE PROVES TO THE WORLD that he
doesn't know what he is talking about.


When Frank is telling us that he only lost on mph at a speed where he is
generating almost his entire output capacity my eyes are rolling and so must everyone's.

No Tommy, the eyes are rolling because you don't know what you are
talking about.
--
cheers,

John B.




--
cheers,

John B.




--
cheers,

John B.

  #307  
Old February 19th 20, 09:45 AM posted to rec.bicycles.tech
Rolf Mantel[_2_]
external usenet poster
 
Posts: 267
Default Better Braking?

Am 18.02.2020 um 23:53 schrieb John B.:
I was replying to Tom who said, "because it has to be pressed very
tightly against the sidewall to keep it was slipping. So it takes
probably two to three times the frictional losses as the light
output."

That simply isn't true.


The order of magnitude is true; sidewall dynamos typically have 10W
braking power for 3W electrical power.
I believe the Sanyo Roller Dynamo had on the order of 6-7W braking poer
for 3W electrical power, (a hub dynamo is on the order of 3W for 3W).
  #308  
Old February 19th 20, 05:24 PM posted to rec.bicycles.tech
Tom Kunich[_2_]
external usenet poster
 
Posts: 1,318
Default Better Braking?

On Monday, February 17, 2020 at 8:48:19 PM UTC-8, Ralph Barone wrote:
On Mon, 17 Feb 2020 06:17:01 -0800 (PST), Tom Kunich
wrote:

I am quite aware that friction losses from a hub generator are minor but
that isn't so for a sidewall generator because it has to be pressed very
tightly against the sidewall to keep it was slipping. So it takes
probably two to three times the frictional losses as the light output.


Er... Tommy, frictional losses in mechanical devices is: " Friction
occurs when two bodies are in contact with each other and have
relative motion".

However you say " pressed very ti...


You seem to have a misunderstanding of frictional losses. The sidewall generator doesn't move relative to the tire but the tire and innertube are displaced because of the pressure of the generator to keep from slipping. There is relative motion but not any sort of slipping or rubbing.

You can also get frictional losses electro-magnetically such as in a hub generator where the magnetic field resists the coils moving through them and turning motion through the field into electrical power.
  #309  
Old February 19th 20, 05:27 PM posted to rec.bicycles.tech
Tom Kunich[_2_]
external usenet poster
 
Posts: 1,318
Default Better Braking?

On Tuesday, February 18, 2020 at 2:21:40 AM UTC-8, wrote:
On Tuesday, February 18, 2020 at 9:32:31 AM UTC+1, John B. wrote:

Of course there is a power loss but it is not the friction between the
generator roller and the tire wall.


Of course there is friction between the generator roller and the tire because the direction of the circumferential speed of the roller is not exactly aligned with that of the tire.

Lou


I suppose you're correct since you are on a tire that has a changing diameter while the roller on the generator has a fixed diameter. But I always had the idea that the real losses were from the displacement of the sidewall.
  #310  
Old February 19th 20, 05:38 PM posted to rec.bicycles.tech
Tom Kunich[_2_]
external usenet poster
 
Posts: 1,318
Default Better Braking?

On Wednesday, February 19, 2020 at 12:45:14 AM UTC-8, Rolf Mantel wrote:
Am 18.02.2020 um 23:53 schrieb John B.:
I was replying to Tom who said, "because it has to be pressed very
tightly against the sidewall to keep it was slipping. So it takes
probably two to three times the frictional losses as the light
output."

That simply isn't true.


The order of magnitude is true; sidewall dynamos typically have 10W
braking power for 3W electrical power.
I believe the Sanyo Roller Dynamo had on the order of 6-7W braking poer
for 3W electrical power, (a hub dynamo is on the order of 3W for 3W).


Lordy how I hate to say it but Frank had a moment of lucidity and pretty well described the problems with sidewall generators. Though I still believe that the majority of losses are from the deformation of he tire and innertube.

If you must have nighttime lighting, you there is simply no competition to a hub generator. Though they are a pain in the butt and usually are only useful on cargo-type bicycles.
 




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Thoughts on braking John Appleby General 76 August 11th 03 10:30 AM


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