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 DiscRelay Circuit Inspection
Remove the relay box (see Relay Box Removal).
Check conductivity of the following numbered terminals
by connecting the hand tester and one 12 V battery to the
relay box as shown in the figure (see Relay Box Internal
Circuit in this section).
If the tester does not read as specified, re ...
Exhaust Device
This motorcycle is equipped with a
exhaust device system. This system
controls the valve in the exhaust pipe
and produces stable engine power at
low and middle engine speed. This exhaust
device is controlled by the ECU,
and adjustment or maintenance should
be done only by a competent mechanic ...
KIBS Servicing Precautions
There are a number of important precautions that should
be followed servicing the KIBS.
This KIBS is designed to be used with a 12 V sealed battery
as its power source. Do not use any other battery
except for a 12 V sealed battery as a power source.
Do not reverse the battery cable connec ...