Engine; Adjusting The Valve Clearance - Yamaha VMAX 2009 Service Manual

EAS20472

ENGINE

EAS20530

ADJUSTING THE VALVE CLEARANCE

The following procedure applies to all of the
valves.
TIP
• Valve clearance adjustment should be made
on a cold engine, at room temperature.
• When the valve clearance is to be measured or
adjusted, the piston must be at top dead center
(TDC) on the compression stroke.
1. Remove:
• Generator cover plate
Refer to "GENERATOR AND STARTER
CLUTCH" on page 5-37.
• Cylinder head covers
Refer to "CAMSHAFTS" on page 5-9.
2. Remove:
• Timing mark accessing screw "1"
• Crankshaft end cover "2"
1 2
3. Measure:
• Valve clearance
Out of specification → Adjust.
Valve clearance (cold)
Intake
0.10–0.17 mm (0.0039–0.0067 in)
Exhaust
0.22–0.29 mm (0.0087–0.0114 in)
TIP
• If the valve clearance is incorrect, record the
measured reading.
• Measure the valve clearance in the following
sequence.
Valve clearance measuring sequence
Cylinder #1 → #3 → #2 → #4
A. Front
M MMM M MMM M M MMM M
Piston #1 TDC
a. Position piston #1 at TDC by turning the
crankshaft counterclockwise until the "T1"
mark "a" on the generator rotor is aligned with
the stationary pointer "b" on the generator
cover.
b a
b. Check that the punch mark "c", punch mark
"d", and "1" mark "e" are aligned as shown.
e
c. Measure the valve clearance with a thickness
gauge.
Thickness gauge
90890-03180
Feeler gauge set
YU-26900-9
L LLL L LLL L L LLL L
M MMM M MMM M M MMM M
Piston #3 TDC
a. Position piston #1 at TDC.
3-4
ENGINE
M MMM M M MMM M M MMM M
d
c
L LLL L L LLL L L LLL L
M MMM M M MMM M M MMM M
MMM
LLL
MMM