Yamaha XT550J - Page 59

Crankshaft
1. Check crankshaft components per chart.
Check connecting rod axial play at
Small end play should not exceed 2
If small end play exceeds 2 mm
small end (to determine the amount
mm (0.079in).
(0.079 in)
disassemble crankshaft,
of wear of crank pin and bearing at
check connecting
rod, crank pin
big end).
and big end bearing.
Replace defective parts. Play after
reassembly should be within 0.8 -
1.0 mm (0.031 - 0.039 in).
Check the
connecting rod side Move the connecting rod to one
If excessive axial play is present,
clearance at big end.
side and insert a
feeler gauge. Big 0.7 mm (0.028
in)
or
more,
end axial play should be within 0.35
disassemble
the crankshaft and
-
0.65 mm (0.014 - 0.026 in).
replace any worn parts.
Check crankshaft assembly runout. Dial gauge readings should be
Correct any misalignment by tapp-
(Misalignment of crankshaft parts.) within 0.03 mm (0.00118 in).
ing the
flywheel with a brass ham-
mer and by using a wedge.
Crankshaft Specifications
Unit: mm (in)
Rod clearance
Runout limit
Assembly
width
C A
Min.
0.03
74.95 - 75.00
0.8
(0.0012)
(2.951 - 2.953)
(0.03)
F
2. In disassembling and reassembling the
crank, follow the illustration.
NOTE: ___________ _
Make sure oil passages of crank and crank pin
are
lined up during assembly.
3-22
Axial "F" Side "0"
Max.
Min.
Max.
2.0
0.3 0.65
(0.08)
(0.0118) (0.0256)
The crankshaft oil passage and the crank pin oil
passage MUST be properly alined. The deviation
of one center line from the other must be
LESS THAN 1 mm.
1. Cran k assembly
2. Crank pin