Removing The Clutch; Checking The Friction Plates; Checking The Clutch Plates; Checking The Clutch Springs - Yamaha YZ450FF 1SL-28199-11 Owner's Service Manual

REMOVING THE CLUTCH

EAS1SL5235
1. Remove:
• Clutch boss nut "1"
• Conical washer "2"
• Clutch boss "3"
TIP
While holding the clutch boss with the clutch
holder "4", loosen the clutch boss nut.
Clutch holder
90890-04086
YM-91042
3

CHECKING THE FRICTION PLATES

EAS1SL5236
1. Check:
• Friction plate
Damage/wear  Replace the friction plates
as a set.
2. Measure:
• Friction plate thickness
Out of specification  Replace the friction
plates as a set.
TIP
Measure it at four points on the friction plate.
Friction plate thickness
2.92–3.08 mm (0.115–0.121 in)
Wear limit
2.85 mm (0.112 in)
1
4
5-41

CHECKING THE CLUTCH PLATES

EAS1SL5237
1. Check:
• Clutch plate
Damage  Replace the clutch plates as a
set.
2. Measure:
• Clutch plate warpage
(with a surface plate and thickness gauge
"1")
Out of specification  Replace the clutch
plates as a set.
Warpage limit
0.10 mm (0.0039 in)
EAS1SL5238

CHECKING THE CLUTCH SPRINGS

1. Check:
• Clutch spring
Damage  Replace the clutch springs as a
set.
2. Measure:
• Clutch spring free length
Out of specification  Replace the clutch
springs as a set.
Clutch spring free length
48.00 mm (1.89 in)
Minimum length
47.00 mm (1.85 in)
CLUTCH