Yamaha YZ250F(S) Owner's Service Manual page 200

VALVE CLEARANCE INSPECTION AND ADJUSTMENT
Remove the valve lifters 1 and the pads
G
2.
NOTE:
Place a rag in the timing chain space to
G
prevent pads from falling into the crank-
case.
Identity each valve lifter and pad position
G
very carefully so that they can be rein-
stalled in their original place.
Select the proper pad using the pad
G
selecting table.
Pad range
No. 120 1.20 mm
~
No. 240 2.40 mm
NOTE:
The thickness a of each pad is indicated in
hundreths of millimeters on the pad upper
surface.
Round off the last digit of the installed pad
G
number to the nearest increment.
Last digit of pad
number
0, 1 or 2
4, 5 or 6
8 or 9
EXAMPLE:
Installed pad number = 148
Rounded off value = 150
NOTE:
Pads can only be selected in 0.05 mm incre-
ments.
Locate the rounded-off value and the mea-
G
sured valve clearance in the chart "PAD
SELECTION TABLE". The field where
these two coordinates intersect shows the
new pad number to use.
NOTE:
Use the new pad number only as a guide
when verifying the valve clearance adjust-
ment.
3 - 21
INSP
ADJ
Pad Availability:
25 increments
Pads are available in
~
0.05 mm increments
Rounded value
0
5
10