Yamaha YZFR1Y(C) 2009, Руководство по обслуживанию

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CONNECTING RODS AND PISTONS
5-79
4. Calculate:
• Piston-pin-to-piston-pin-bore clearance
Out of specification
→
Replace the piston
pin and piston as a set.
EAS14B1023
CHECKING THE CONNECTING RODS
1. Measure:
• Crankshaft-pin-to-big-end-bearing clear-
ance
Out of specification
→
Replace the big
end bearings.
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The following procedure applies to all of the
connecting rods.
ECA13930
Do not interchange the big end bearings
and connecting rods. To obtain the correct
crankshaft-pin-to-big-end-bearing clear-
ance and prevent engine damage, the big
end bearings must be installed in their orig-
inal positions.
a. Clean the big end bearings, crankshaft
pins, and the inside of the connecting rods
halves.
b. Install the big end upper bearing into the
connecting rod and the big end lower bear-
ing into the connecting rod cap.
TIP
Align the projections “a” on the big end bear-
ings with the notches “b” in the connecting rod
and connecting rod cap.
c. Put a piece of Plastigauge® “1” on the
crankshaft pin.
d. Assemble the connecting rod halves.
TIP
• Do not move the connecting rod or crank-
shaft until the clearance measurement has
been completed.
• Lubricate the bolt threads with molybdenum
disulfide oil.
• Make sure that the “Y” mark “c” on the con-
necting rod faces towards the left side of the
crankshaft.
• Make sure that the characters “d” on both the
connecting rod and connecting rod cap are
aligned.
Piston-pin-to-piston-pin-bore clearance = Pis-
ton pin bore inside diameter “b” - Piston pin
outside diameter “a”
Piston-pin-to-piston-pin-bore
clearance
0.002–0.022 mm (0.0001–
0.0009 in)
Limit
0.072 mm (0.0028 in)
Crankshaft-pin-to-big-end-bear-
ing clearance
0.034–0.058 mm
(0.0013–0.0023 in)
Limit
0.09 mm (0.0035 in)