Replace it if necessary.

Inner Tube Inspection
Spring Tension InspectionCrankshaft Sensor Peak Voltage Inspection
Refer to the Crankshaft Sensor Peak Voltage Inspection
in the Electrical System chapter.
If the reading is within the standard, remove the ECU and
check the wiring for continuity between harness connectors.
Special Tool - Hand Tester: 57001-1394
Disconnect the ECU and sensor connector ...
Subthrottle Sensor Output Voltage Inspection
Measure the output voltage at the subthrottle sensor in
the same way as input voltage inspection, note the following.
Disconnect the subthrottle sensor connector and connect
the setting adapter [A] between these connectors.
Special Tool - Throttle Sensor Setting Adapter: 57001
-1538
...
Crankcase Splitting
Remove the engine (see Engine Removal in the Engine
Removal/Installation chapter).
Set the engine on a clean surface and hold the engine
steady while parts are being removed.
Remove:
Cylinder Head (see Cylinder Head Removal in the Engine
Top End chapter)
Starter Motor (see Starter M ...