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 TestThrottle Body Assy Assembly
Before assembling, blow away dirt or dust from the throttle
body and delivery pipe assy by applying compressed air.
Replace the O-rings [A] of the joint pipe [B] with new ones.
Apply engine oil to the new O-rings, and insert it to the
delivery pipes [C].
Insert the joint pipe so th ...
Starter Motor Installation
NOTICE
Do not tap the starter motor shaft or body. Tapping
the shaft or body could damage the motor.
Clean the starter motor legs [A] and crankcase where the
starter motor is ground.
Replace the O-ring [A] with a new one.
Apply grease to the new O-ring.
Tighten:
Torque - Starter ...
Immobilizer Amplifier Replacement
Remove the upper fairing assembly (see Upper Fairing
Assembly Removal in the Frame chapter).
Disconnect the connector [A].
Pull out the immobilizer amplifier [B] together with the rubber
protector [C] from the air intake duct [D].
ECU Replacement
Refer to the ECU Removal/Instal ...