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 InspectionStarter Motor Disassembly
Remove the starter motor (see Starter Motor Removal).
Take off the starter motor through bolts [A] and remove
the both end covers [B].
Pull out the armature [A] out of the yoke [B].
NOTE
Do not remove the circlip [C] from the shaft.
Remove the starter motor terminal lock ...
Exhaust Butterfly Valve Actuator Installation
Install the pulley [A] on the actuator so that the hole side
[B] align with the groove [C] on the shaft.
Make sure that the groove on the shaft is pointing toward
the center of the screw [D].
If the shaft position is incorrect, refer to the following
NOTE and procedures to electrically ad ...
Handlebar Removal
Remove:
Steering Damper (see Steering Damper Removal)
Clutch Lever Clamp Bolts [A]
Clutch Lever Assembly [B]
Left Switch Housing [C]
Handlebar Weight [D]
Left Handlebar Grip [E]
Remove:
Front Master Cylinder [A] (see Front Master Cylinder Removal
in the Brakes chapter)
...