Yamaha MX775, Service Manual

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PERIOD
IC
CHECK
S AN
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JU
STMEN
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PERIODIC MAINTENANCE
6.
Adjust:
• Adjust to original set value
TIP
• When adjust valve clearance, record the measured read-
ing of current.
• Measure the valve clearance in the following sequence.
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a. Remove the rocker arm “1” and the adjusting pad
“2”.
(Refer to “CYLINDER HEAD COVERS, CYLINDER
HEADS” on page 3-20)
TIP
• Pay attention so that the push rod does not fall into the
cylinder head.
• Make a note of the position of each adjusting pad “3” so
that they can be installed in the correct place.
b. Calculate the difference between the specified
valve clearance and the measured valve clearance.
Example:
Specified valve clearance = 0.07–0.13 mm (0.003–
0.005 in)
Measured valve clearance = 0.18 mm (0.007 in)
0.18 mm (0.007 in)–0.13 mm (0.005 in) = 0.05 mm
(0.002 in)
Valve clearance (cold):
Normal ENG operation range (between
1000 hr periodic maintenance):
Intake: 0.02–0.2 mm (0.0008–0.01 in)
Exhaust: 0.02–0.2 mm (0.0008–0.01 in)
Original set value (adjust at 1000 hr peri-
odic maintenance):
Intake: 0.07–0.13 mm (0.003–0.005 in)
Exhaust: 0.07–0.13 mm (0.003–0.005 in)
#1
#2
Valve clearance measuring sequence
Cylinder #2

#1
1
2
2
3