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 WearSpecifications
Connecting Rod Big End Bearing Insert Selection
Crankshaft Main Bearing Insert Selection
*: The bearing inserts for Nos. 2 and 4 journals have an oil groove,
respectively. ...
Rear Wheel Removal
Raise the rear wheel off the ground with the stand [A].
Remove:
Cotter Pin [A]
Rear Axle Nut [B]
Washer [C]
Rear Axle [D] (from Right Side)
Remove the rear wheel rotation sensor from the caliper
bracket (see Rear Wheel Rotation Sensor Removal in the
Brakes chapter).
...
Upper Crankcase Assembly
When installing the breather plate, replace the gasket [A]
with a new one.
Apply a non-permanent locking agent to the threads of
the bolts [A] and tighten them.
Torque - Breather Plate Bolts: 9.8 N·m (1.0 kgf·m, 87 in·lb)
Install the fitting [A] until it is bottomed ...