I have a '06 WR450 and am having a problem with the headlight. The bulb was burned out so I replaced it. It worked when at idle, but quickly burned out when I went for a ride around the block. I checked the voltage going to the light and it was ~ 15V at idle, but goes up above 20V with engine rpms. I'm guessing I have a problem with the regulator? Anyone had a similar issue?