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 InspectionFront Fender Removal
Remove:
Bolts [A] with Washers (Both Sides)
Reflectors (Both Sides, US, CA, CAL and AU Models)
Front Fender [B]
Take the brake hose off the clamp [C] (both sides).
Front Fender Installation
Apply a non-permanent locking agent to the front fender
mounting bolts.
Tighten:
...
Spark Plug Replacement
Remove the stick coils (see Stick Coil Removal in the
Electrical System chapter).
Remove the spark plugs using the 16 mm (0.63 in.) plug
wrench [A] vertically.
Replace the spark plug with new ones.
Standard Spark Plug
Type: NGK CR9EIA-9
Insert the spark plug vertically into the sp ...
Brakes
Brake Wear Inspection
Inspect the brakes for wear. For each
front and rear disc brake caliper, if the
thickness of either pad is less than
1 mm (0.04 in.), replace both pads
in the caliper as a set. Pad replacement
should be done by an authorized
Kawasaki dealer.
A. Lining Thickness
B. ...