Yamaha MX360 - Installing the Crankcase Cover; Checking the Cylinder and Piston

PISTON, CAMSHAFT, CRANKCASE, AND CRANKSHAFT
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ENGINE
INSTALLING THE CRANKCASE COVER
1.
Install:
• Crankcase cover
• Crankcase cover bolts “1” to “8”
TIP
Tighten the bolts to the specified torque in two steps and in
order from “1” to “8”.
CHECKING THE CYLINDER AND PISTON
1.
Check:
• Piston wall
• Cylinder wall
Vertical scratches  Replace the cylinder, and
replace the piston and piston rings as a set.
2.
Measure:
• Cylinder warpage
TIP
Measure the warpage on the contact surface of the cylin-
der head at six points using a straight edge and thickness
gauge.
Out of specification  Replace the crankcase
assembly.
3.
Measure:
• Piston-to-cylinder clearance
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Measure cylinder bore “C” with the cylinder bore
gauge.
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Crankcase cover bolt:
1st: 12 N·m (1.2 kgf·m, 8.9 lb·ft)
2nd: 30 N·m (3.0 kgf·m, 22 lb·ft)
T
R
.
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Thickness gauge:
90890-03268
Feeler gauge set:
YU-26900-9
Warpage limit:
0.05 mm (0.002 in)