Yamaha XZ550RJ 1982 Service Manual page 63

1. As shown in the photo, set the special tool
set, and using a hydraulic press, pull the
main bearing out to the outside of the
crankcase.
1. Special tool 2. Crankcase
4. Main bearing
2. Clean the counterbore in the crankcase
where the main bearing is fitted, and meas-
ure the diameter of the counter-bore. By re-
ferring to the table below, choose the proper
over-size main bearing.
3. Hydraulic press
CAUTION:
The diameter of counterbore should be meas-
ured at two places, and the average of the two
measurements should be used to choose the
bearing.
NOTE:
If the diameter of the counterbore in the crank-
case exceeds 49.020mm (1.9299 in), the crank-
case should be replaced with a new one. The new
crankcase is already fitted with main bearings, and
their inside diameters are normally 45.000 to
45.012mm (1.77147 -1.7721 in).
3. As shown in the photo, fit an over-size bear-
ing over the special tool.
1. Special tool 2. Main bearing
NOTE:
As shown in the photo, fit the key vertically to the
bearing, and align the straight cutaway of the plate
(special tool) with the key, then grip the bearing
with the tool set.
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