Jasen Betts wrote in a message to MIKE ROSS:

 MR> I've read that the brightness of white leds is getting to the
 MR> point that headlights will be next. I'll believe it when I see it
 MR> but I was thinking of bundling up a few and try them out on my
 MR> bicycle light. It uses about 3 Watts right now (6Vac 0.5A) but if
 MR> I can reduce this by a factor of 10 (6 leds at 50mW each) my legs
 MR> will definitely thank me!

 JB> I've not seen a constant voltage dynamo used on a bicycle...
 JB> (actually I've not seen an dynamo on a bicycle for many years) My
 JB> dad had used to burn out lights by riding too fast, until he got
 JB> higher voltage bulbs...

Another easy fix for that is to use a current-regulator.  Something like an
LM317 (?) and a resistor,  in line with the lamps...

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