hi A colleague of mine has an 07 wr450f, his coils burned out.. the yamaha dealer said it was because he never replaced the headlight bulb, read post below and tell me if you agree, cause now im worried about the same thing.. "Apparantly it has to do with the light, I was at Cyclelec today in joburg they are rewinding my coil for R480.00. The 2007/early 2008 models had a problem which has been sorted out. The light forms part of the electrical circuit (check your manual shows clearly) when the bulb blows it cuases the battery to overcharge cooking the regulator which in turn pops the coil / then drains your battery. If you cook the coils they cost R1050.00 from Yamaha or R480.00 to repair. The same story has been confirmed with three other Yamaha mechanics " does this make sense. or anyone have similar issues?