When the engine is running, the air intake valve is lifting up.
If the valve does not operate properly, check the air intake solenoid valve hoses for leak.
If there are no leaks, check the air intake solenoid valve.

Air Intake Solenoid Valve Unit TestPremuffler 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 ...
Daily Checks
Check the following items each day before you ride. The time required is
minimal,
and habitual performance of these checks will help ensure you a safe, reliable
ride.
If any irregularities are found during these checks, refer to the Maintenance
and
Adjustment chapter or see your dealer fo ...
Gear Position Switch Inspection
NOTE
Be sure the transmission and external shift mechanism
are good condition.
Remove the fuel tank (see Fuel Tank Removal in the Fuel
System (DFI) chapter).
Disconnect the connector [A].
Set the hand tester [A] to the × 1 kΩ or × 100 Ω range
and connect i ...