Checking The Camshaft Sprockets - Yamaha YZF-R25 Service Manual

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)
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a. Install the camshafts into the cylinder head
(without the camshaft caps).
b. Position a strip of Plastigauge® "1" onto the
camshaft journal as shown.
c. Install the dowel pins and camshaft caps.
TIP
• Tighten the camshaft cap bolts in the tighten-
ing sequence as shown.
• Do not turn the camshaft when measuring the
camshaft journal-to-camshaft cap clearance
with the Plastigauge®.
Camshaft cap bolt
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
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3
5
3
5
d. Remove the camshaft caps, and then mea-
sure the width of the Plastigauge® "1".
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5. Measure:
• Camshaft journal diameter "a"
Out of specification → Replace the camshaft.
Within specification → Replace the cylinder
head and camshaft caps as a set.
EAS30936

CHECKING THE CAMSHAFT SPROCKETS

1. Check:
• Camshaft sprocket
More than 1/4 tooth wear "a" → Replace the
camshaft sprockets and timing chain as a set.
5-15
CAMSHAFTS
1 6
4
2
1 6
2 4
1
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Camshaft journal diameter
22.459–22.472 mm (0.8842–
0.8847 in)
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