A
A Muzi
Guest
> On 26 Jan 2007 17:35:19 -0800, [email protected] wrote:
>> The advantages of a good hub generator are usually lack of slippage,
>> and efficiency - at least, while the lights are on. (Some Shimanos are
>> draggy with lights off.)
Andrew Price wrote:
> How noticeable is that?
The only hard data we have is that at 15kph, an XT hub drags at 80g/cm,
a Sanyo Dynohub at 116g/cm with the lamp off and 150g/cm with the lamp
lit. (newer hubs seem if anything more free. Surely not more drag)
Spin an XT hub. Pretty free, eh? About double that, or -
short answer = 6v 2.4W is "not enough to notice when riding"
With a black plastic bag over the lamp and switch, I tried reaching
across to another rider's bike in daylight flipping the covered switch
as he tried to tell when the covered lamp was on or off. Can't tell
riding. My own bikes have no switch (just another corrosion magnet)
lamps always on.
You may confuse a rough feeling when spinning the axle in your fingers
with a real-world rim and tire moving the thing smoothly and briskly.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
>> The advantages of a good hub generator are usually lack of slippage,
>> and efficiency - at least, while the lights are on. (Some Shimanos are
>> draggy with lights off.)
Andrew Price wrote:
> How noticeable is that?
The only hard data we have is that at 15kph, an XT hub drags at 80g/cm,
a Sanyo Dynohub at 116g/cm with the lamp off and 150g/cm with the lamp
lit. (newer hubs seem if anything more free. Surely not more drag)
Spin an XT hub. Pretty free, eh? About double that, or -
short answer = 6v 2.4W is "not enough to notice when riding"
With a black plastic bag over the lamp and switch, I tried reaching
across to another rider's bike in daylight flipping the covered switch
as he tried to tell when the covered lamp was on or off. Can't tell
riding. My own bikes have no switch (just another corrosion magnet)
lamps always on.
You may confuse a rough feeling when spinning the axle in your fingers
with a real-world rim and tire moving the thing smoothly and briskly.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971