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 InspectionCrankshaft Sensor Removal
Remove:
Fuel Tank (see Fuel Tank Removal in the Fuel System
(DFI) chapter)
Crankshaft Sensor Lead Connector [A]
Remove:
Right Lower Fairing (see Lower Fairing Removal in the
Frame chapter)
Bolts [A]
Crankshaft Sensor Cover [B] and Gasket
Oil Pressure Switch Terminal [C]
...
Lubrication
It is important to lubricate rotating or sliding parts during
assembly to minimize wear during initial operation. Lubrication
points are called out throughout this manual, apply
the specific oil or grease as specified.
Direction of Engine Rotation
When rotating the crankshaft by hand, the fre ...
Water Temperature Sensor Resistance Inspection
Refer to the Water Temperature Sensor Inspection in the
Electrical System chapter.
If the reading is within the standard, but the problem still
exists, replace the ECU (see ECU Removal/Installation in
the Fuel System (DFI) chapter).
Water Temperature Sensor Circuit
1. ECU
2. Water T ...