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 TestCylinder Head Warp Inspection
Clean the cylinder head.
Lay a straightedge across the lower surface of the cylinder
head at several positions.
Use a thickness gauge [A] to measure the space between
the straightedge [B] and the head.
Cylinder Head Warp
Standard: – – –
Service Limit: 0.05 mm (0.0020 in.)
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Brake Fluid Level Inspection
Check that the brake fluid level in the front brake reservoir
[A] is above the lower level line [B].
NOTE
Hold the reservoir horizontal by turning the handlebar
when checking brake fluid level.
If the fluid level is lower than the lower level line, fill the
reservoir to the upper lev ...
Liquid Gasket, Non-permanent Locking Agent
For applications that require Liquid Gasket or a
Non-permanent Locking Agent, clean the surfaces so
that no oil residue remains before applying liquid gasket or
non-permanent locking agent. Do not apply them excessively.
Excessive application can clog oil passages and
cause serious damage.
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