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 DiscAir Suction System Damage Inspection
Separate the air switching valve hose [A] from the lower
air cleaner housing [B] (see Air Cleaner Housing Removal
in the Fuel System (DFI) chapter).
Connect the following parts temporarily.
Fuel Pump Lead Connector [A]
Extension Tube [B]
Air Cleaner Housing (see Air Cleaner Hou ...
Rear Shock Absorber Scrapping
WARNINGPressurized nitrogen may explode when
heated.
The rear shock contains nitrogen gas. To avoid
an explosion, do not incinerate the shock body
without first releasing the nitrogen and removing
the shraeder valve.
Remove the rear shock absorber (see Rear Shock Ab ...
Flap and Rear Fender Rear Installation
Installation is the reverse of removal. Note the following.
Fit the tab [A] to the slot [B].
Run the seat lock cable [C] between the tool kit case and
the turn signal light as shown in the figure.
When installing the dampers [A] on the lower pipe [B],
install it as shown in the figure. ...