2004 Official factory service manual for Yamaha YFZ450S ATV Quad., Page 288Get this manual
FRONT ARMS AND FRONT SHOCK ABSORBER ASSEMBLIES EBS00472
CHECKING THE BALL JOINTS The following procedure applies to both of the front arm ball joints1Check: ball joint (upper front arm) Damagepitting Replace the upper front armFree play Replace the front armTurns roughly Replace the upper front arm2Check: ball joint (lower front arm) Damagepitting Replace the ball jointFree play Replace the ball jointTurns roughly Replace the ball jointMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM