Checking The Camshafts - Yamaha TMAX XP530E-A 2017 Service Manual

3
EAS30257

CHECKING THE CAMSHAFTS

1. Check:
• Camshaft lobes
Blue discoloration/pitting/scratches  Re-
place the camshaft.
2. Measure:
• Camshaft lobe dimensions "a"
Out of specification  Replace the camshaft.
Camshaft lobe dimensions
Lobe height (Intake)
32.490–32.590 mm (1.2791–
1.2831 in)
Limit
32.390 mm (1.2752 in)
Lobe height (Exhaust)
32.690–32.790 mm (1.2870–
1.2909 in)
Limit
32.590 mm (1.2831 in)
3. Measure:
• Camshaft runout
Out of specification  Replace.
Camshaft runout limit
0.030 mm (0.0012 in)
4. Measure:
• Camshaft-journal-to-camshaft-cap clearance
Out of specification  Measure the camshaft
journal diameter.
Camshaft-journal-to-camshaft-
cap clearance
0.028–0.062 mm (0.0011–0.0024
in)
Limit
0.080 mm (0.0032 in)
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a. Install the camshaft into the cylinder head
(without the dowel pins and camshaft caps).
b. Position a strip of Plastigauge® "1" onto the
camshaft journal as shown.
c. Install the dowel pins and camshaft caps.
TIP
• When tightening the camshaft cap, tighten the
four bolts on the both ends of the cap tempo-
rarily to lower the entire cap, while paying at-
tention not to twist the dowel pins and camshaft
journal. After the camshaft cap touches the cyl-
inder head, tighten the two bolts in the middle
to the specified torque and then the remaining
four bolts to the specified torque.
• To prevent the camshaft cap from cracking,
tighten the camshaft cap carefully by tapping
the camshaft using a soft-face hammer (both
for temporary and final tightening).
• Do not turn the camshaft when measuring the
camshaft journal-to-camshaft cap clearance
5-10
CAMSHAFTS
1