Checking The Big End Bearings - Yamaha YZF-R1 98 Service Manual

CONNECTING RODS AND PISTONS
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4. Calculate:
• piston-pin-to-piston-pin-bore clear-
ance
Out of specification → Replace the pis-
ton pin.
Piston-pin-to-piston-pin-bore clearance =
Piston pin bore diameter (in the
piston) –
Piston pin outside diameter
Piston-pin-to-piston-pin-bore
clearance
0.002 ~ 0.022 mm
<Limit>: 0.072 mm

CHECKING THE BIG END BEARINGS

1. M easure:
• crankshaft-pin-to-big-end-bearing
clearance
Out of specification → Replace the big
end bearings.
Crankshaft-pin-to-big-end-
bearing clearance
0.016 ~ 0.040 mm
The follow ing procedure applies to all of
the connecting rods.
CAUTION:
ACHTUNG:
Do not interchange the big end bearings
and connecting rods. To obtain the cor-
rect crankshaft-pin-to-big-end-bearing
clearance and prevent engine damage,
the big end bearings must be installed
in their original positions.
a. Clean the big end bearings, crank-
shaft pins, and bearing portions of
the connecting rods.
b. Install the big end upper bearing into
the connecting rod and the big end
low er bearing into the connecting rod
cap.
NOTE:
Align the projections a on the big end
bearings w ith the notches b in the con-
necting rod and connecting rod cap.
ENG