Yamaha YZ450F(S), Owner'S Service Manual

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4 - 31
ENG
CYLINDER HEAD
ASSEMBLY AND INSTALLATION
1. Install:
●
Timing chain guide (front) 1
●
Dowel pin 2
●
Cylinder head gasket 3
●
Cylinder head 4
NOTE:
While pulling up the timing chain, install the
timing chain guide (front) and cylinder head.
New
2. Install:
●
Plain washer 1
●
Bolt [L=160 mm (6.30 in)] 2
●
Bolt [L=150 mm (5.91 in)] 3
Installation steps:
CAUTION:
Tighten the cylinder head using the rota-
tion angle procedure to obtain uniform
tightening torque.
●
Wash the threads and contact surfaces of
the bolts, the contact surfaces of the plain
washers, the contact surface of the cylin-
der head, and the threads of the crank-
case.
●
Apply the molybdenum disulfide grease on
the threads and contact surfaces of the
bolts and on both contact surfaces of the
plain washers.
●
Install the plain washers and bolts.
●
Tighten the bolts to the specified torque in
two or three steps in the proper tightening
sequence as shown.
T
R
.
.
Bolts (cylinder head):
1st:
30 Nm (3.0 m • kg, 22 ft • lb)