Adjust the engine idle speed periodically on the engine at normal operating temperature.
To adjust the idle speed:

Engine oil and filter change
Throtile cable playThrotile cable play
This motorcycle has a twin throttle
cable system. Cable A is for pulling
cable and cable B is for
returning.
To adjust the cable play:
Loosen the lock nut 1.
Turn the adjuster 2 so that the
throttle grip has 2.0 - 4.0 Mm
(0.08- 0.16 In) play.Tighten the lock nut 1.
...
DTC “c31” (p0705): gp switch circuit
malfunction
Detected condition and possible cause
Detected condition
Possible cause
No gear position switch voltage
Gp switch voltage is not within the following range.
Gp switch voltage > 0.6 V
Gp switch circuit open or short.
Gp switch malfunction.
...
Cylinder head related parts inspection
Refer to “cylinder head disassembly and assembly” .
Cylinder head distortion
Decarbonize the combustion chambers.
Check the gasket surface of the cylinder head for
distortion. Use a straightedge and thickness gauge.
Take clearance readings at several places. If
readings exceed the ...