Yamaha YZ450F(E) 2014 - Checking the Camshaft

CAMSHAFT
5-14
EAS1SL1209
CHECKING THE CAMSHAFT
1. Check:
• Camshaft lobes
Blue discoloration/pitting/scratches  Re-
place the camshaft.
2. Measure:
• Camshaft lobe dimensions “A” and “B”
Out of specification  Replace the cam-
shaft.
3. Measure:
• Camshaft runout
Out of specification  Replace.
4. Measure:
• Camshaft-journal-to-camshaft-cap clear-
ance
Out of specification  Measure the cam-
shaft journal diameter.
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a. Install the camshaft into the cylinder head.
b. Position a strip of Plastigauge® “1” onto the
camshaft journal as shown.
Camshaft lobe dimensions
Intake A
37.730–37.830 mm (1.4854–
1.4894 in)
Limit
37.630 mm (1.4815 in)
Intake B
27.950–28.050 mm (1.1004–
1.1043 in)
Limit
27.850 mm (1.0965 in)
Exhaust A
33.540–33.640 mm (1.3205–
1.3244 in)
Limit
33.440 mm (1.3165 in)
Exhaust B
24.769–24.869 mm (0.9752–
0.9791 in)
Limit
24.669 mm (0.9712 in)
1
2
3
Camshaft runout limit
0.015 mm (0.0006 in)
Camshaft-journal-to-camshaft-
cap clearance
0.028–0.062 mm (0.0011–0.0024
in)
1