Cylinder/Piston Specifications - DAELIM HISTORY 125 Service Manual

10. CYLINDER / PISTON
SERVICE INFORMATION · · · · · · 10-1
TROUBLESHOOTING· · · · · · · · 10-1
CYLINDER· · · · · · · · · · · · · · · · · · 10-2
SERVICE INFORMATION
GENERAL SAFETY
● Be careful not to damage the mating surfaces by using a screwdriver when disassembling the cylinder. Do not strike the
cylinder too hard during disassembly, even with a rubber or plastic mallet, to prevent the possibility of damage to the
cylinder fins.
● Take care not to damage the cylinder wall and piston.
● Check parts after disassembling, and clean and dry with an air hose prior to taking measurements.
SPECIFICATIONS
CYLINDER
PISTON SKIRT OUTER DIAMETER
PISTON PIN HOLE INNER DIAMETER
PISTON,
PISTON-TO-PISTON PIN CLEARANCE
PISTON PIN,
PISTON RING-TO-
PISTON RING
GROOVE CLEARANCE
PISTON RING
JOINT GAP
CYLINDER-TO-PISTON CLEARANCE
CONNECTING ROD SMALL END INNER DIAMETER
GAP BETWEEN CONNECTING ROD SMALL END AND PISTON PIN
TROUBLESHOOTING
Comperssion too low
● Worn piston
● Worn, damaged piston ring
● Worn cylinder
Excessive smoke
● Worn cylinder, piston or piston rings
● Improper installation of piston ring
● Scored or scratched piston or cylinder wall
ITEM
INNER DIAMETER
TAPER
OUT-OF-ROUND
HEAD CONTACT WARPAGE
PISTON PIN OUTER DIAMETER
SECOND
TOP / SECOND
OIL RING (SIDE RAIL)
PISTON / PISTON RING · · · · 10-3
CYLINDER INSTALLATION · · 10-5
STANDARD VALUE
56.000-56.010 mm
55.925-55.945 mm
15.002-15.008 mm
14.994-15.000 mm
0.002-0.014 mm
0.040-0.067 mm
TOP
0.025-0.052 mm
0.10-0.25 mm
0.20-0.70 mm
0.055-0.090 mm
15.010-15.028 mm
0.010-0.034 mm
Overheating
● Excessive carbon build-up on top of piston
Abnormal noise
● Worn cylinder and piston
● Worn connecting rod small end bearing or piston pin
● Damaged piston ring
● Excessive carbon build-up on top of piston
Unit : mm
SERVICE LIMIT
56.100 mm
- 0.050 mm
- 0.005 mm
- 0.020 mm
58.825 mm
15.040 mm
14.960 mm
0.020 mm
0.110 mm
0.080 mm
0.50 mm
1.10 mm
0.200 mm
15.060 mm
0.040 mm
10
10-1