Cylinder/Piston - KYMCO AGILITY 125 Service Manual

8

. CYLINDER/PISTON

SERVICE INFORMATION.......................8-1
TROUBLESHOOTING..............................8-1
CYLINDER REMOVAL ...........................8-2
SERVICE INFORMATION
GENERAL INSTRUCTIONS
The cylinder and piston can be serviced with the engine installed in the frame.
After disassembly, clean the removed parts and dry them with compressed air before inspection.
SPECIFICATIONS
Item
I.D.
Warpage
Cylinder
Cylindricity
True roundness
Ring-to-
clearance
Ring end gap
Piston,
piston ring
Piston O.D.
Piston O.D. measuring
Piston-to-cylinder clearance
Piston pin hole I.D.
Piston pin O.D
Piston-to-piston pin clearance
Connecting rod small end I.D. bore
TROUBLESHOOTING
When hard starting or poor performance at low speed occurs, check the crankcase breather for
white smoke. If white smoke is found, it means that the piston rings are worn, stuck or broken.
Compression too low or uneven
compression
Worn, stuck or broken piston rings
Worn or damaged cylinder and piston
Compression too high
Excessive carbon build-up in combustion
chamber or on piston head
8-1
Top
Second
Top
Second
Oil side rail
9mm from bottom of skirt
PISTON REMOVAL................................. 8-2
PISTON INSTALLATION........................ 8-6
CYLINDER INSTALLATION ................. 8-6
Standard (mm)
50.00-50.01
0.015-0.050
0.015-0.050
0.08-0.20
0.05-0.20
0.20-0.70
49.97-49.990
0.010-0.040
13.002-13.008
12.994-13.000
0.002-0.014
13.016-13.034
Excessive smoke from exhaust muffler
Worn or damaged piston rings
Worn or damaged cylinder and piston
Abnormal noisy piston
Worn cylinder, piston and piston rings
Worn piston pin hole and piston pin
AGILITY 50
Service Limit (mm)
0.05
0.05
0.05
0.09
0.09
0.45
0.45
49.9
0.1
13.04
12.96
13.06