Checking The Crankshaft - Yamaha 2014 MT-07 Service Manual

B
For example, if the crankcase J
er shaft web J numbers are 6 and 5 respec-
1
tively, then the bearing size for J
J (crankcase) – J (balancer shaft web)
1 1
= 6 – 5 =
1 (blue)
Bearing color code
1.Blue 2.Black 3.Brown 4.Green
5. Yellow
EAS31075

CHECKING THE CRANKSHAFT

1. Check:
• Balancer drive gear
Damage/wear → Replace the balancer drive
gear and balancer shaft assembly as a set.
Excessive noise during operation → Replace
the balancer drive gear and balancer shaft
assembly as a set.
2. Measure:
• Crankshaft runout
Out of specification → Replace the crank-
shaft.
Runout limit
0.030 mm (0.0012 in)
3. Check:
• Crankshaft journal surfaces
• Crankshaft pin surfaces
• Bearing surfaces
Scratches/wear → Replace the crankshaft.
CRANKSHAFT AND BALANCER SHAFT
J1 J2 J3
and balanc-
1
is:
1
4. Measure:
• Crankshaft-journal-to-crankshaft-journal-
bearing clearance
Out of specification → Replace the crank-
shaft journal bearings.
Journal oil clearance
0.018–0.042 mm (0.0007–0.0017
in)
ECA13920
NOTICE
Do not interchange the crankshaft journal
bearings. To obtain the correct crankshaft-
journal-to-crankshaft-journal-bearing clear-
ance and prevent engine damage, the crank-
shaft journal bearings must be installed in
their original positions.
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a. Clean the crankshaft journal bearings, crank-
shaft journals, and bearing portions of the cyl-
inder and crankcase.
b. Install the crankshaft journal upper bearings
"1" and the crankshaft into the cylinder.
TIP
Align the projections "a" on the crankshaft jour-
nal upper bearings with the notches "b" in the
cylinder.
c. Put a piece of Plastigauge® "2" on each
crankshaft journal.
TIP
Do not put the Plastigauge® over the oil hole in
the crankshaft journal.
5-89
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a
b
1
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