Yamaha XP500 Service Manual page 133

ADJUSTING THE VALVE CLEARANCE
a
1
7. Measure:
• valve clearance
Out of specification → Adjust.
M MMM
b
a. Turn the crankshaft counterclockwise.
b. When piston #1 is at TDC on the compres-
sion stroke, align the "I" mark a on the A.C.
magneto rotor with the stationary pointer b
on the A.C. magneto cover.
NOTE:
• TDC on the compression stroke can be
found when the camshaft lobes are turned
away from each other.
• In order to be sure that the piston is at TDC,
the alignment mark c on the intake cam-
shaft sprocket and the alignment mark d on
the exhaust camshaft sprocket must align
with the cylinder head mating surface as
shown in the illustration.
c. Measure the valve clearance with a thick-
ness gauge 1.
NOTE:
• If the valve clearance is incorrect, record the
measured reading.
• Measure the valve clearance in the following
sequence.
d. Turn the crankshaft 360° counterclockwise
and check the valve clearance of piston #2.
L LLL
3 - 12
Valve clearance (cold)
Intake valve
0.15 ~ 0.20 mm
(0.0059 ~ 0.0079 in)
Exhaust valve
0.25 ~ 0.30 mm
(0.0098 ~ 0.0118 in)
M MMM M M MMM M M MMM M
Thickness gauge
90890-03079, YM-34483
L LLL L L LLL L L LLL L
CHK
ADJ
M MMM M M MMM M MMM
L LLL L L LLL L LLL