Replace the caliper if the cylinder and piston are badly scores or rusty.
Front Caliper [C] Rear Caliper [D]


Rear Caliper Dust Boot and Friction Boot Damage
Rear Caliper Holder Shaft WearCoupling Bearing Removal
Remove:
Coupling
Grease Seal
Circlip [A]
Special Tool - Inside Circlip Pliers: 57001-143
Remove the bearing [A] by tapping from the wheel side.
Special Tool - Bearing Driver Set [B]: 57001-1129
...
Interlock Operation Inspection
Raise the rear wheel off the ground with the stand [A].
1st Check
Start the engine to the following conditions
Condition:
Transmission Gear → 1st Position
Clutch Lever → Release
Sidestand → Down or Up
Turn the ignition switch to ON and push the starter butto ...
Piston Installation
Apply molybdenum disulfide oil solution to the oil ring expander,
and install the oil ring expander [A] in the bottom
piston ring groove so the ends [B] not butt together
Applymolybdenum disulfide oil solution to the oil ring steel
rails, and install the oil ring steel rails, one above th ...