The rings should fit perfectly parallel to groove surfaces.
If not, replace the piston and all the piston rings.

Piston Ring/Groove Clearance Standard:
Top 0.03
0.07 mm (0.0012
0.0028 in.)
Second 0.03
0.06 mm (0.0012
0.0024 in.)
Service Limit:
Top 0.17 mm (0.0067 in.)
Second 0.16 mm (0.0063 in.)
Piston Wear Inspection
Piston Ring Groove Width InspectionClutch 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 ...
Front Wheel Installation
NOTE
The direction of the wheel rotation [A] is shown by an
arrow [B] on the wheel spoke.
Check the wheel rotation mark on the front wheel and
install it.
Apply high-temperature grease to the grease seal lips.
Fit the collars [A] on the both sides of the hub.
The collars are i ...
Valve Installation
NOTICE
Do not lap the valve to the valve seat, using the
grinding compound. It will come off oxide film
treated surface of the valve.
Replace the oil seal with a new one.
Apply a thin coat of molybdenum disulfide grease to the
valve stem before valve installation.
Install the springs so ...