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12
Main parts fit clearances
No.
Description
Prescribed dimensions (mm)
Type of fit
Assembly
tolerance (mm)
1
Exhaust valve seat
insert/exhaust valve
Φ44.5
025
.
0
0
/Φ44.5
095
.
0
070
.
0
interference 0.045
~
0.095
2
Intake
valve
seat
insert/exhaust seat
Φ48.5
025
.
0
0
/Φ48.5
139
.
0
114
.
0
interference 0.089
~
0.139
3
Valve guide/cylinder
head valve guide hole
Φ16
018
.
0
0
/Φ16
046
.
0
028
.
0
interference 0.010
~
0.046
4
Valve guide/exhaust
valve stem
Φ9.5
019
.
0
0
/Φ9.5
04
.
0
062
.
0
radial
clearance
0.040
~
0.081
5
Valve
guide/intake
valve stem
Φ9.5
019
.
0
0
/Φ9.5
025
.
0
047
.
0
radial
clearance
0.025
~
0.066
6
Rocker arm bush/
rocker arm shaft
Φ25
021
.
0
0
/Φ25
02
.
0
041
.
0
radial
clearance
0.020±0.062
7
Cylinder
bore/diameter of the
lower part of the
piston skirt
Φ108
022
.
0
0
/Φ107.86±0.01
radial
clearance
0.130
~
0.172
8
Valve tappet/cylinder
block tappet hole
Φ28
052
.
0
0
/Φ28
02
.
0
041
.
0
radial
clearance
0.020
~
0.093