1990-2004 Yamaha YFM350X Warrior Factory Service Manual, Page 136Get this manual
IIANOSJP -HEADLIGHT BULB REPLACEMENT
Avoid touching glass part of bulbAlso keep it free from oil otherwise, transparency of glass, bulb life and iIIuminous flux will be adversely affectedIf oil gets on bulb, clean it with cloth moistened thoroughly with alcohol or lacquer thinner