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 InspectionWindshield
Windshield Removal
Remove:
Bolts [A] and Washers
Windshield [B]
Windshield Installation
Be sure to install the wellnuts [A] and the washers.
Tighten:
Torque - Windshield Mounting Bolts: 1.2 N·m (0.12 kgf·m,
11 in·lb)
...
Sidestand Removal
Raise the rear wheel off the ground with the stand [A].
Remove:
Sidestand Switch Bolt [A]
Sidestand Switch [B]
Remove:
Spring [A]
Sidestand Nut [B]
Sidestand Bolt [C]
Sidestand [D]
...
Crankcase Splitting
Remove the engine (see Engine Removal in the Engine
Removal/Installation chapter).
Set the engine on a clean surface and hold the engine
steady while parts are being removed.
Remove:
Cylinder Head (see Cylinder Head Removal in the Engine
Top End chapter)
Starter Motor (see Starter M ...