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 InspectionParts 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
...
Lower Fairing Removal
Remove the quick rivets [A].
Remove:
Quick Rivets [A]
Bolts [B]
Pull up the core by the flat-head screwdriver (–), and then
remove the quick rivet.
Clear the hook portions on the upper edges [C] from the
slots, and remove the left lower fairing [D].
While pulling down ...
Special Tools
Fork Oil Level Gauge:
57001-1290
Vacuum Gauge:
57001-1369
Hand Tester:
57001-1394
Throttle Sensor Setting Adapter #1:
57001-1400
Peak Voltage Adapter:
57001-1415
Needle Adapter Set:
57001-1457
Throttle Sensor Setting Adapter:
57001-1538
Measuring Adapter:
57001-1700
...