2004 Official factory service manual for Yamaha YFZ450S ATV Quad., Page 135Get this manual
REPLACING HEADLIGHT BULB a 1
6Install: bulb holder headlight bulb holder cover NOTE: After installing the bulb holder cover, make sure that the "TOP" mark is in the position shown7 Connect: headlight lead coupler Install: headlight Refer to "SEAT, FENDERS AND FUEL TANK"