Joyner TROOPER T2 Owner's Manual page 95

4.2.6. Check the clearance of piston ring
ends
4.2.6.1. Put the piston ring i n the position
which is 45 mm under the cylinder hole
top surface, in order to make the piston
ring keep flattened, you can press the
piston ring with piston top surface, then
use a piston gauge to measure the open
clearance.
Benchmark(mm)
Primary ring
0.25-0.40
Secondary ring 0.35~0.50
Oil ring 0.20~0.70
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.
Limit (mm)
0.65
0.65
1.00
Inside diameter
Measure position
95
Outside diameter
Measure position