If the measurement is under service limit, replace the piston.

Piston Diameter
Standard: 75.959
75.974 mm
(2.9905
2.9911 in.)
Service Limit: 75.81 mm (2.985 in.)
Cylinder (Upper Crankcase) Wear Inspection
Piston Ring, Piston Ring Groove Wear InspectionAxle Inspection
Remove the front and rear axles (see Front/Rear Wheel
Removal).
Visually inspect the front and rear axle for damages.
If the axle is damaged or bent, replace it.
Place the axle in V blocks that are 100 mm (3.94 in.) [A]
apart, and set a dial gauge [B] on the axle at a point
halfway ...
Front Fork Oil Change
Remove the front fork (see Front Fork Removal (Each
Fork Leg)).
Turn the spring preload adjuster fully counterclockwise for
removing the piston rod assy easily.
Hold the inner tube lower end in a vise.
Using the wrench [A], unscrew the top plug [B] out of the
outer tube.
Special Too ...
Break-in
The first 1 600 km (1 000 mi) that the motorcycle is ridden is designated
as the
break-in period. If the motorcycle is not used carefully during this period, you
may
very well end up with a “broken down” instead of a “broken in” motorcycle after
a
few thousand kilometers.
The fol ...