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 TestUpper Fairing Assembly Disassembly
Remove:
Upper Fairing Assembly (see Upper Fairing Assembly
Removal)
Headlight (see Headlight Removal/Installation in the
Electrical System chapter)
City Light (LED) (see City Light (LED) Removal/Installation
in the Electrical System chapter)
Remove the screws [A], and separate each ...
Radiator and Radiator Fan Installation
If the radiator bracket [A] was removed, install it.
Install the radiator fan to the radiator
Tighten the radiator fan mounting bolts.
When installing the pad [B], install it so that the upper end
of the pad aligns with the corner top [C].
When install the pad [D], install it so that the ...
Air Switching Valve Installation
Install the air switching valve [A] with hose [B] as shown
in the figure.
Front [C]
Left Side View [D]
White Paint [E]
Air Switching Valve Operation Test
Refer to the Air Suction System Damage Inspection in the
Periodic Maintenance chapter.
Air Switching Valve Unit Test ...