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 TestRegulator/Rectifier Inspection
Remove:
Upper Fairing Assembly (see Upper Fairing Assembly
Removal in the Frame chapter)
Right Inner Fairing (see Inner Fairing Removal in the
Frame chapter)
Bolts [A]
Regulator/Rectifier [B]
Set the hand tester to the × 1 kΩ range and make the
measurements show ...
Vehicle-down Sensor Installation
Be sure to install the rubber dampers [A] and collars [B]
on the bracket.
The UP mark [A] of the sensor should face upward.
WARNINGIncorrect installation of the vehicle-down
sensor
could cause sudden loss of engine power. The
rider could lose balance during certain ...
Exhaust Pipe Installation
Replace the exhaust pipe gaskets [A] and premuffler
chamber gasket [B] with new ones.
Install the premuffler chamber gasket to the premuffler
chamber [C] until it is bottomed so that the chamfer side
faces exhaust pipe [D].
Install the exhaust pipe clamp [E] as shown in the figure.
I ...