Joyner JNSZ1100SV Owner's Manual page 82

4.2.7. Check the clearance between the
piston and the cylinder wall The
positions for measuring the inner
diameter of the cylinder and the
piston skirt are as shown in the right
figure. Replace and repair the piston
or the cylinder body, or bore the
cylinder if the measured results
exceed the limits
[Benchmark] 0.018～0.03
[Limit] 0.10
[Reference] The clearance between the
piston and the cylinder hole is subject to
the innermost diameter of cylinder in
vertical direction minus the maximum outer
diameter of the piston.
4.2.7.1. After the replacement of the piston
or the cylinder body, it is needed to
confirm the clearance of the
replaced cylinder once again.
Datum: 0.018～0.030
4.3. Crankshaft
4.3.1. Check the coaxiality of the main
shaft diameter
4.3.1.1. Use the centimeter to measure the
coaxiality.
Replace the crankshaft if the measurement
result exceeds t he limit.
[Limit] 0.03mm
Attention: The bending value should be
1/2 of the fluctuation for one circle of
turning the crankshaft.
4.3.2. Check the tears and wears of the
crankshaft
4.3.2.1. Use a caliper to measure the shaft
diameter, and work out the
circularity and cylindricity.
[Limit] 0.005mm
4.3.2.2. Use a caliper to measure the
connecting rod diameter, and work
out the circularity and cylindricity.
[Limit] 0.004mm
the measuring position is shown as the
figure,
Inside diameter
Measure position
Outside diameter
Measure position