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 InspectionPressure Testing
Remove:
Upper Fairing Assembly (see Upper Fairing Assembly
Removal in the Frame chapter)
Radiator Cap [A]
Remove the radiator cap in two steps. First turn the cap
counterclockwise to the first stop. Then push and turn it
further in the same direction and remove the cap.
Install the ...
Wiring Diagram (Other than US, CA and CAL with KIBS Models)
ZX1000KC
ZX1000KD
...
Parts Removal/Installation
WARNINGGasoline is extremely flammable and can be
explosive
under certain conditions. Turn the ignition
switch OFF. Do not smoke. Make sure the area is
well-ventilated and free from any source of flame
or sparks; this includes any appliance with a pilot
light.
NOTICE
...