Yamaha YZ250 2021 Owner's Manual

CLUTCH5-1EAM20111CLUTCHEAM30108REMOVING THE CLUTCH1. Remove:• Clutch boss nut “1”• Lock washer• Clutch boss “2”TIP• While holding the clutch boss with the univer-sal clutch holder “3”, loosen the clutch bossnut.• Do not use an impact wrench for removing theclutch boss nut.EAM30109CHECKING THE FRICTION PLATES1. Check:• Friction plateDamage/wear  Replace the friction platesas a set.2. Measure:• Friction plate thicknessOut of specification  Replace the frictionplates as a set.TIPMeasure it at four points on the friction plate.EAM30110CHECKING THE CLUTCH PLATES1. Check:• Clutch plateDamage  Replace the clutch plates as aset.2. Measure:• Clutch plate warpage(with a surface plate and thickness gauge)Out of specification  Replace the clutchplates as a set.EAM30111CHECKING THE CLUTCH SPRINGS1. Check:• Clutch springDamage  Replace the clutch springs as aset.2. Measure:• Clutch spring free lengthOut of specification  Replace the clutchsprings as a set.EAM30112CHECKING THE CLUTCH HOUSING1. Check:• Clutch housing dogsDamage/pitting/wear  Deburr the clutchhousing dogs or replace the clutch housing.TIPPitting on the clutch housing dogs will cause er-ratic clutch operation.Universal clutch holder90890-04086Universal clutch holderYM-91042Friction plate thickness2.90–3.10 mm (0.114–0.122 in)Wear limit2.80 mm (0.110 in)123G088993Thickness gauge90890-03268Feeler gauge setYU-26900-9Clutch plate thickness1.50–1.70 mm (0.059–0.067 in)Warpage limit0.20 mm (0.008 in)Clutch spring free length44.00 mm (1.73 in) (YZ250X)50.00 mm (1.97 in) (YZ250)Clutch spring free length limit41.80 mm (1.65 in) (YZ250X)48.00 mm (1.89 in) (YZ250)G088994