A Non-friction bicycle lights generator (dynamo)

This is somewhat disingenuous. It is like saying windage on a bicycle is not friction.

-- Ferme le Bush

I remember "frictionless" dynamos on bikes in UK more than 50 years ago: they were incorporated into the hub of the wheel. I'm assuming that the windings were in the stationary part and that the hub had permanent magnets in it.

Perce

On 11/09/05 07:01 pm snipped-for-privacy@yahoo.com tossed the following ingredients into the ever-growing pot of cybersoup:

LED's require little power- that is why you may not feel a "drag" However, you, as the person pushing the pedals, do supply all the energy and losses involved in this device. If tumbling the magnets takes no energy, the output will be the same- zilch, zero, nada.

No free ride (or light).

IMHO, this is the main advantage of this system - it only generates enough power to flash some LEDs and thus, mechanically, imposes an insignificant load - compared to a normal generator.

The main load will be an aerodynamic one. The magnet is fixed to the spokes and rotated with the wheel and is generating drag continuously. Whereas the generator will only impose a load as the magnet passes by. As a generating system, its efficiency will be very low.

Now, if they had fitted the magnet into the centre of a plastic reflector, which all road bikes should have at night, then it would have been a complete night safety lighting system..

u need gassin boy!

------------- I agree with your points.

My beef is the "no friction, no drag" claim. negligible drag-OK- (also negligable power). A battery powered setup might be cheaper overall and pulse rate is independent of wheel speed. Note the little Christmas Brooches with several flashing LED's

insignificant

i hear the Polish version uses solar power :)