HYOSUNG RX 125 Service Manual page 48

PISTON-CYLINDER CLEARANCE
As a result of the above measurement, if the piston
to cylinder clearance exceeds the limit shown in the
table below, overhaul the cylinder and use an over-
size piston, or replace both cylinder and piston.
Piston cylinder clearance
PISTON RING-GROOVE CLEARANCE
Using a thickness gauge, measure the side clearance
of the 1st and 2nd rings. If any of the clearances
exceeds the limit, replace both piston and piston rings.
Thickness gauge : 09900-20803
Piston ring-groove clearance
1st
2nd
Piston ring-groove width
1st
2nd
Oil
PISTON RING FREE END GAP AND
PISTON RING END GAP
Before installing piston rings, measure the free end
gap of each ring using vernier calipers.
Next, fit the ring in the cylinder, and measure each
ring end gap using a thickness gauge.
If any ring has an excess end gap, replace the ring.
Piston ring free end gap(Free condition)
Piston ring free end gap
1st R
2nd RN
Vernier calipers : 09900-20101
Piston ring free end gap(Assembly condition)
Piston ring free end gap
1st and 2nd
Thickness gauge : 09900-20803
Piston ring thickness
Piston ring thickness
1st
2nd
Service limit 0.120 mm
Service limit
0.180 mm
0.150 mm
Standard
1.01~1.03 mm
1.01~1.03 mm
2.01~2.03 mm
R : (RIKEN)
Service limit
5.7 mm
4.6 mm
Service limit
0.50 mm
Standard
0.970~0.990 mm
0.970~0.990 mm
ENGINE 3-18