If the disc has worn past the service limit, replace it.
Measuring Area [B]

Brake Disc Thickness Standard:
Front 5.3
5.7 mm (0.21
0.22 in.)
Rear 4.8
5.2 mm (0.19
0.20 in.)
Service Limit:
Front 5.0 mm (0.20 in.)
Rear 4.5 mm (0.18 in.)
Brake Disc Installation
Brake Disc Warp InspectionRear Fender Front Removal
Remove:
Flap and Rear Fender Rear (see Flap and Rear Fender
Rear Removal)
Fuel Tank (see Fuel Tank Removal in the Fuel System
(DFI) chapter)
Battery (see Battery Removal in the Electrical System
chapter)
Exhaust Butterfly Valve Actuator (see Exhaust Butterfly
Valve Actuator Remova ...
Premuffler Chamber Removal
Remove:
Muffler Body (see Muffler Body Removal)
Right Lower Fairing (see Lower Fairing Removal in the
Frame chapter)
Front Seat (see Front Seat Removal in the Frame chapter)
Oxygen Sensor (Equipped Models) (see Oxygen Sensor
Removal (Equipped Models) in the Electrical System
chapter ...
Spark Plug Condition Inspection
Remove the spark plugs (see Spark Plug Replacement in
the Periodic Maintenance chapter).
Visually inspect the spark plugs.
If the spark plug center electrode [A] and/or side electrode
[B] are corroded or damaged, or if the insulator [C]
is cracked, replace the plug.
If the spark plug is ...