Yamaha MBK X-MAX 300 2017, Service Manual

Page: 218 / 462

CAMSHAFT
5-23
EAS30256
REMOVING THE CAMSHAFT
1. Remove:
• Camshaft assembly “1”
TIP
Screw the M6 bolts “2” into the threaded end of
the camshaft assembly, and then pull out the
camshaft.
EAS32364
CHECKING THE CAMSHAFT ASSEMBLY
1. Check:
• Camshaft lobes
Blue discoloration/pitting/scratches
→
Re-
place the camshaft assembly.
2. Measure:
• Camshaft lobe dimensions “a”
Out of specification
→
Replace the camshaft
assembly.
3. Measure:
• Camshaft runout
Out of specification
→
Replace the camshaft
assembly.
4. Check:
• Camshaft oil passage
Obstruction
→
Blow out with compressed air.
5. Check:
• Decompression system
TIP
• Check that the decompression lever moves
smoothly.
• Check that the operating range “a” of the de-
compression lever is the same as the range
shown in the illustration.
EAS30259
CHECKING THE ROCKER ARMS AND
ROCKER ARM SHAFTS
The following procedure applies to all of the
rocker arms and rocker arm shafts.
1. Check:
• Rocker arm
• Rocker arm roller “1”
Damage/wear
→
Replace.
Camshaft lobe dimensions
Lobe height (Intake)
40.017–40.117 mm (1.5755–
1.5794 in)
Limit
39.917 mm (1.5715 in)
Lobe height (Exhaust)
39.954–40.054 mm (1.5730–
1.5769 in)
Limit
39.854 mm (1.5691 in)
2
1
Camshaft runout limit
0.030 mm (0.0012 in)
a. 9.69°
a