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a. Remove the mounting bolts (
Figure 72
) from
the bracket, and pull the assembly from the
crankcase.
b. Fit the new cam chain assembly into place.
Install the mounting bolts and torque them to
10 N•m (89 in.-lb.).
5. Replace any part that is worn or damaged.
VALVES AND VALVE COMPONENTS
Complete valve service requires a number of spe-
cial tools. The following procedures describe how
to check valve components and determine the
needed service.
A valve spring compressor (Yamaha part No.
YM-04019 or 90890-04019), or equivalent, is
needed to remove and install the valves.
Valve Removal
Refer to
Figure 73
.
CAUTION
Keep the components of each particu
lar valve assembly together. Do not
mix components from different valve
assemblies or excessive wear may oc
cur.
1. Remove the cylinder head as described in this
chapter.
110
CHAPTER FOUR
72
73
VALVE
ASSEMBLY
1. Valve keepers
2. Spring retainers
3. Valve spring
4. Oil seal
5. Spring seat
6. Valve
74
VALVE LIFTER BORE
PROTECTOR
5 mm
5 mm
15 mm
31 mm
Top view
25 mm outside diamter
(when compressed)
71