Use a vernier caliper at several points around the piston.
Piston Ring Groove Width Standard:
Top [A] 0.82
0.84 mm (0.0323
0.0331 in.)
Second [B] 0.82
0.84 mm
(0.0323
0.0331 in.)
Service Limit:
0.92 mm (0.036 in.)
Second 0.92 mm (0.036 in.)

If the width of any of the two grooves is wider than the service limit at any point, replace the piston.
Piston Ring, Piston Ring Groove Wear Inspection
Piston Ring Thickness InspectionSprocket Wear Inspection
Visually inspect the engine and rear sprocket teeth for
wear and damage.
If the teeth are worn as illustrated, replace the sprocket,
and inspect the drive chain wear (see Drive Chain Wear
Inspection in the Periodic Maintenance chapter).
Worn Tooth (Engine Sprocket) [A]
Worn Tooth (Rear ...
Clutch Installation
Apply engine oil to the needle bearing [A] and the sleeve
[B].
Install:
Needle Bearing
Sleeve
Install the clutch housing [A].
Fit the holes [B] and projections [C].
Engage the clutch housing gear and the crankshaft primary
gear.
Install the spacer [A] and the clutch ...
Oil Level Inspection
Check that the engine oil level is between the upper [A]
and lower [B] levels in the gauge.
NOTE
Situate the motorcycle so that it is perpendicular to the
ground.
If the motorcycle has just been used, wait several minutes
for all the oil to drain down.
If the oil has just been changed, ...