Yamaha WR450F Owner's Service Manual page 274

2. Install:
• Primary driven gear "1"
• Thrust washer "2"
• Clutch boss "3"
TIP
Apply the engine oil on the primary driven gear
inner circumference.
3. Install:
• Conical washer "1"
• Clutch boss nut "2"
Clutch boss nut
75 Nm (7.5 m·kgf, 54 ft·lbf)
ECA1DX1020
NOTICE
Make sure to tighten to specification; other-
wise, it may damage the other part that is
fastened together.
TIP
• Install the conical washer with its convex sur-
face "a" outward.
• Apply engine oil to the threads and contact
surface of the clutch boss nut.
• Apply engine oil to the contact surfaces of the
conical washer.
• Use the clutch holding tool "3" to hold the
clutch boss.
Universal clutch holder
90890-04086
Universal clutch holder
YM-91042
New
4. Install:
• Friction plate 1 "1"
• Clutch plate 2 "2"
• Cushion spring "3"
• Friction plate 2 "4"
• Clutch plate 1 "5"
TIP
• Install the clutch plates and friction plates al-
ternately on the clutch boss, starting with a
friction plate and ending with a friction plate.
• From the clutch boss side, install the friction
plates in order: friction plate 1  2, friction
plate 2 (identification color: purple)  5, and
friction plate 1  1.
• From the clutch boss side, the clutch plate in
order: clutch plate 2 (thickness: 1.6 mm)  3,
and clutch plate 1 (thickness: 2.0 mm)  4.
• Apply the engine oil on the friction plates and
clutch plates.
1
4
5
1
4
a. Identification color
6-47
CLUTCH
a 2
3
1
2
4 1
2
5 2 3
2
a
1
3
4
5