Yamaha 2007 XP500, Service Manual

Page: 108 / 450

ENGINE
3-4
●
In order to be sure that the piston is at TDC, the
alignment mark
“ c ” on the intake camshaft
sprocket and the alignment mark “ d ” on the ex-
haust camshaft sprocket must align with the
cylinder head mating surface as shown in the
illustration.
c. Measure the valve clearance with a thickness
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.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
8. Remove:
●
Intake camshaft
●
Exhaust camshaft
CAUTION:
ECA15B1015
Before removing the camshafts from the cyl-
inder head, tilt up the engine at least 25
°
.
NOTE:
●
Refer to “ CAMSHAFTS ” on page 5-6.
●
When removing the timing chain and cam-
shafts, fasten the timing chain with a wire to re-
trieve it if it falls into the crankcase.
9. Adjust:
●
Valve clearance
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Remove the valve lifter “ 1 ” and the valve pad
“ 2 ” with a valve lapper “ 3 ” .
NOTE:
●
Cover the timing chain opening with a rag to
prevent the valve pad from falling into the
crankcase.
●
Make a note of the position of each valve lifter
“ 1 ” and valve pad “ 2 ” so that they can be in-
stalled in the correct place.
b. Select the proper valve pad from the follow-
ing table.
Valve clearance measuring sequence
Cylinder #1
→
#2
→
#4
→
#3
Cylinder #2 180
°
Cylinder #4 360
°
Cylinder #3 540
°
c
d
1
Valve lapper
90890-04101
Valve lapping tool
YM-A8998
Valve pad range Nos. 120
–
240
1
2
2
1