Replace any damaged gears or gears with excessively worn dogs or dog holes.

Shift Fork Guide Pin/Drum Groove Wear InspectionWater Pump Impeller Disassembly/Assembly
Remove the water pump impeller (see Oil Pump Removal
in the Engine Lubrication System chapter).
The sealing seat and rubber seal may be removed easily
by hand.
Apply coolant around the surfaces of the rubber seal and
sealing seat.
Install the rubber seal [A] and sealing seat [B] into ...
Mode-switching
Depress the S-KTRC button on the left handlebar switch
to change the mode. The mode can be changed only when
the throttle grip is closed completely.
The S-KTRC OFF can be selected only when the motorcycle
is at a stop. Changing to mode 1 from S-KTRC OFF
is possible while riding.
NOTE
...
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
...