Replace the wheel rotation sensor if it is cracked, bent, or otherwise damaged.

Rear Wheel Rotation Sensor Installation
Wheel Rotation Sensor Air Gap InspectionSwingarm Installation
Visually inspect the chain guide [A].
Replace the chain guide if it shows any signs of abnormal
wear or damage.
Apply a non-permanent locking agent to the threads of
the chain guide bolt [B].
Apply plenty of grease to the lip of the oil seals [A].
Be sure to install the oil seals ...
Idle Speed Control Valve Actuator Input Voltage Inspection
NOTE
Be sure the battery is fully charged.
Turn the ignition switch to OFF.
Disconnect the idle speed control valve actuator connector
and connect a suitable measuring leads [A] between
these connectors as shown in the figure.
Main Harness [B]
Idle Speed Control Valve Actua ...
Transmission Assy Removal
Remove:
Engine Sprocket (see Engine Sprocket Removal in the
Final Drive chapter)
Gear Position Switch (see Gear Position Switch Removal
in the Electrical System chapter)
Collar [A]
O-ring [B]
Remove:
Clutch (see Clutch Removal in the Clutch chapter)
Shift Shaft Assembly ...