Piston Ring End Gap Standard:
Top 0.20
0.30 mm (0.0079
0.0118 in.)
Second 0.35
0.50 mm (0.0138
0.0197 in.)
Service Limit: Top 0.6 mm (0.024 in.)
Second 0.8 mm (0.031 in.)
If the end gap of either ring is greater than the service limit, replace all the rings.

Piston Ring Thickness Inspection
BalancerCylinder (Upper Crankcase) Wear Inspection
Split the crankcase (see Crankcase Splitting).
Remove the pistons (see Piston Removal).
Assemble the cylinder (upper crankcase) [A], the cylinder
head [B] and the cylinder head gasket [C].
Tighten the cylinder head bolts (see Cylinder Head Installation
in the Engine Top End chapter).
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Handlebar Installation
Apply a non-permanent locking agent to the threads of
the handlebar positioning bolts and tighten them.
Torque - Handlebar Positioning Bolts: 9.8 N·m (1.0 kgf·m,
87 in·lb)
Install the steering stem head with handlebars.
Install the washer [A] and steering stem head nut [B].
Tighten:
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Seat Cutter Operation Care
1. This valve seat cutter is developed to grind the valve for
repair. Therefore the cutter must not be used for other
purposes than seat repair.
2. Do not drop or shock the valve seat cutter, or the diamond
particles may fall off.
3. Do not fail to apply engine oil to the valve seat cutter
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