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 InspectionStator Coil Installation
Apply a non-permanent locking agent to the threads of
the stator coil bolts and tighten them.
Torque - Stator Coil Bolts: 12 N·m (1.2 kgf·m, 106 in·lb)
Using a high flash-point solvent, clean off any oil or dirt
that may be on the silicone sealant coating area. Dry
them with a clea ...
Air Switching Valve
Air Switching Valve Operation Test
Refer to the Air Suction System Damage Inspection in the
Periodic Maintenance chapter.
Air Switching Valve Unit Test
Remove the air switching valve (see Air Switching Valve
Removal in the Engine Top End chapter).
Set the hand tester [A] to the × 1 ...
Amplifier Input Voltage Inspection
NOTE
Be sure the battery is fully charged.
Turn the ignition switch to OFF.
Remove the upper fairing (see Upper Fairing Removal in
the Frame chapter).
Do not disconnect the connectors.
Connect a digital meter to the amplifier connector [A] with
needle adapter set.
Special To ...