Removing The Clutch; Checking The Friction Plates; Checking The Clutch Plates; Checking The Clutch Springs - Yamaha WR450F 2021 Owner's Service Manual

EAM30108

REMOVING THE CLUTCH

1. Remove:
• Clutch boss nut "1"
• Lock washer "2"
• Clutch boss "3"
TIP
• Straighten the lock washer tab.
• While holding the clutch boss with the univer-
sal clutch holder "4", loosen the clutch boss
nut.
Universal clutch holder
90890-04086
Universal clutch holder
YM-91042
1 1 1
EAM30109

CHECKING THE FRICTION PLATES

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 1 thickness
2.92–3.08 mm (0.115–0.121 in)
Wear limit
2.82 mm (0.111 in)
Friction plate 2 thickness
2.92–3.08 mm (0.115–0.121 in)
Wear limit
2.82 mm (0.111 in)
EAM30110

CHECKING THE CLUTCH PLATES

1. Check:
• Clutch plate
Damage  Replace the clutch plates as a
2 2
3 3
4 4
5-49
set.
2. Measure:
• Clutch plate warpage
(with a surface plate and thickness gauge)
Out of specification  Replace the clutch
plates as a set.
Thickness gauge
90890-03268
Feeler gauge set
YU-26900-9
Warpage limit
0.10 mm (0.004 in)
EAM30111

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)
Clutch spring free length limit
45.60 mm (1.80 in)
EAM30112

CHECKING THE CLUTCH HOUSING

1. Check:
• Clutch housing dogs "1"
Damage/pitting/wear  Deburr the clutch
housing dogs or replace the clutch housing.
TIP
Pitting on the clutch housing dogs will cause er-
ratic clutch operation.
EAM30113

CHECKING THE CLUTCH BOSS

1. Check:
• Clutch boss splines
CLUTCH
1 1 1