Yamaha FJR13AG, Service Manual

Page: 345 / 784

CAMSHAFTS
5-16
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.
3. Measure:
• Camshaft runout
Out of specification
→
Replace.
4. Measure:
• Camshaft-journal-to-camshaft-cap clearance
Out of specification
→
Measure the camshaft
journal diameter.
▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼▼▼
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
• Tighten the camshaft cap bolts in stages and in
a crisscross pattern, working from the inner
caps out.
• Do not turn the camshaft when measuring the
camshaft journal-to-camshaft cap clearance
with the Plastigauge®.
d. Remove the camshaft caps and then mea-
sure the width of the Plastigauge® “1”.
Camshaft lobe dimensions
Lobe height (Intake)
33.050–33.150 mm (1.3012–
1.3051 in)
Limit
32.950 mm (1.2972 in)
Lobe height (Exhaust)
33.050–33.150 mm (1.3012–
1.3051 in)
Limit
32.950 mm (1.2972 in)
Camshaft runout limit
0.030 mm (0.0012 in)
Camshaft-journal-to-camshaft-
cap clearance
0.028–0.062 mm (0.0011–0.0024
in)
T
R
.
.
Camshaft cap bolt
10 Nm (1.0 m·kgf, 7.2 ft·lbf)