http://en.red-dot.org/index.php?id=1835

 

How much air resistance compared to a hubgenerator ?

Youre already pushing your torso through the air anyway, so I doubt you can measure any difference.

Hub generators are cool. I almost bought an REI Fusion city bike with one. It has automatic dual beam lights.



Thing is, a hub generator will cost you at least $150 to retrofit when all said is done.

$80 for the hub + spokes + labor.

and whats wrong with a good old dinamo rubbing against the wheel ?

It makes a sound and feels heavy to pedal but u can turn it off unlike the hub or fan though

Quote from: knightyand whats wrong with a good old dinamo rubbing against the wheel ?

Nothing for short trips, but both the Shimano and the wind thingie incorporate batteries, so youre really charging those and have a light at a stop. Plus they offer almost no rolling resistance or noise. Dynamos can also be hard to fit on some bike, and not everyone want to run tires with a dyno track.

If I think of any more reasons, Ill post again.

My preference would be for a hub dyno, really you can get high power LED lights that use well under a watt for a reasonable beam anyway so the stress shouldnt be that great.

they give 6 volt  3w I do not know how well they work with a low load.

They are constant current devices so dynamos and LEDs tend to be more expensive as LEDs do not like running at 50v.

Theyll supply 3w when correctly loaded. otherwise their voltage will go up like crazy.

Wind gennies seem pointless. big, more drag, and generally an eyesore.

Whats wrong with normal battery ones?

Quote from: sdpWhats wrong with normal battery ones?

I have to replace my batteries on my normal battery ones about once a week. Rechargable batts are great, but lights become unusable on roads well before its a good time to recharge them.

Dynamos make lighting a non issue, its as easy as flicking a switch and voomf! you have light.