If any is worn down to the service limit, replace the brush assy.
Starter Motor Brush Length [B] Standard: 12.05 mm (0.4744 in.) Service Limit: 6.55 mm (0.258 in.)

Starter Motor Assembly
Commutator Cleaning and InspectionCheck 3-6: Neutral Indicator Light (LED) Inspection
Connect the leads in the same circuit as Check 3-2.
Connect the terminal [8] to the battery (–) terminal.
Check that the neutral indicator light (LED) [A] goes on.
If the indicator light does not go on, replace the meter unit.
...
ESD (Electronic Steering Damper) ECU Communication Error (Service Code 3C,
ZX1000JD/KD)
ESD ECU Communication Line Inspection
When the data (for status of ESD system) is not sent from
the ESD ECU to the meter unit and ECU, the service code
3C is displayed.
The data is sent through the CAN communication line.
The service code 3C is detected with the meter unit.
The FI symbol does ...
Swingarm Removal
Remove:
Rear Wheel (see Rear Wheel Removal in the
Wheels/Tires chapter)
Mud Guard with Rear Brake Hose (see Mud Guard Removal
in the Frame chapter)
Rocker Arm (see Rocker Arm Removal)
Remove:
Brake Hose Clamp Bolt [A]
Unscrew the swingarm pivot shaft nut [A].
Usi ...