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 InspectionPiston Removal
Remove:
Crankshaft (see Crankshaft Removal)
Remove the piston together with the connecting rod to the
cylinder head side.
NOTICE
Discard the connecting rod bolts and nuts. To prevent
damage to the crankpin surfaces, do not allow
the connecting rod bolts to bump against the
crankpins. ...
Parking
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 ...
Check 2-1: Speedometer Inspection
Using the suitable stand, raise the rear wheel off the
ground.
Rotate the rear wheel by hand or start the engine.
Check that the display changes speedometer.
If the display function does not work, check the following
parts.
Rear Wheel Rotation Sensor (see Wheel Rotation Sensor
Inspe ...