If a master cylinder or piston shows any damage, replace them.

If a cup is worn, damaged softened (rotted), or swollen, the piston assembly should be replaced to renew the cups.
If fluid leakage is noted at the brake lever, the piston assembly should be replaced to renew the cups.
If they are damaged, replace them.
If the springs are damaged, replace them.
If the relief port becomes plugged, the brake pads will drag on the disc. Blow the ports clean with compressed air.
Front Master Cylinder [I] Rear Master Cylinder [J]

Rear Master Cylinder Installation
Brake DiscParking
WARNINGOperating or parking the vehicle
near flammable materials can
cause a fire, and can result in
property damage or severe personal
injury.
Do not idle or park your vehicle
in an area where tall or dry vegetation,
or other flammable materials
could come into cont ...
Exhaust Butterfly Valve Actuator Sensor Input Voltage Inspection
NOTE
Be sure the battery is fully charged.
Turn the ignition switch to OFF.
Remove the front seat (see Front Seat Removal in the
Frame chapter).
Remove the screws [A] and the exhaust butterfly valve
actuator temporarily with the cables installed.
Disconnect the exhaust butterf ...
Rocker Arm Removal
Squeeze the brake lever slowly and hold it with a band.
Remove the front footpeg bracket bolts.
Raise the rear wheel off the ground with the jack (see
Rear Shock Absorber Removal).
Special Tools - Jack: 57001-1238
Jack Attachment: 57001-1608
Remove:
Lower Rear Shock Absorber B ...