Oh! Something just occured to me. I'm not sure if you were informed of this or not, but most of those generator lights are completely un-regulated. In otherwords, the faster you go, the more power it generates, period. This has the undesirable side effect of speeds over 20mph overloading, and killing the light bulb. I used to have a generator set on my bike until I started working on "Project Dragonfly", and did preliminary speed calculations. Was originally going to build a regulator system for the lights, then decided it was too much hassle and simply switched to a battery-operated Blackburn light kit. One of my co-workers mentioned something about using a "Zeiner Diode" if you are interested, however. Voltage regulation might prove a workable solution if you have access to a Radio Shack, and don't mind a little soldering.
~DakotaLynx