Yamaha 2011 WR250FA, Owner'S Service Manual

Page: 98 / 316

3-23
ENGINE
In order to be sure that the piston is at Top
Dead Center, the punch mark "c" on the ex-
haust camshaft and the punch mark "d" on the
intake camshaft must align with the cylinder
head surface, as shown in the illustration.
c. Measure the valve clearance "e" using a
feeler gauge "1".
Record the measured reading if the clearance
is incorrect.
6. Adjust:
• Valve clearance
Adjustment steps:
a. Remove the camshaft (intake and exhaust).
Refer to "CAMSHAFTS" section in the
CHAPTER 5.
b. Remove the valve lifters "1" and the pads
"2".
• Place a rag in the timing chain space to pre-
vent pads from falling into the crankcase.
• Identity each valve lifter and pad position very
carefully so that they can be reinstalled in
their original place.
c. Select the proper pad using the pad select-
ing table.
The thickness "a" of each pad is indicated in
hundredths of millimeters on the pad upper sur-
face.
d. Round off the last digit of the installed pad
number to the nearest increment.
Pad range
Pad Availability: 25
increments
No. 120–
No. 240
1.20 mm–
2.40 mm
Pads are available in
0.05 mm increments