5. CYLINDER HEAD/CYLINDER/PISTON
5-2
Maintenance Information
Precautions In Operation
z
The inspection and maintenance of the cylinder head, cylinder and piston can be carried as
engine mounted on the body.
z
It should clean the engine to prevent dirt from entering into cylinder and crankcase before
removal.
z
Remove all washes from the interfaces of cylinder head, cylinder and crankcase.
z
Be careful do not damage cylinder head, cylinder and piston when removing.
z
Inspect the removed & cleaned parts thoroughly, and apply with oil onto the rotation surfaces
before installation.
Specification
JET 50 series
JET 100 series
Item
Standard value
(mm)
Limit (mm)
Standard value
(mm)
Limit (mm)
Cylinder
head
Deformation
- 0.100 - 0.100
Piston OD
39.030~39.045
38.935
51.030~39.045
50.935
Clearance between
cylinder and piston
0.040~0.050 0.100 0.040~0.050 0.100
Piston pin hole
12.002~12.008
12.030
14.002~14.008
14.030
Piston pin OD
11.994~12.000
11.970
13.994~14.000
13.970
Clearance between
piston and piston pin
0.002~0.014 0.030 0.002~0.014 0.030
Piston ring end gap
0.100~0.250
0.400
0.100~0.250
0.400
Piston
ID of connecting rod
small end
17.05~17.015 17.025 17.05~17.015 17.025
ID 39.000~39.015
39.050
51.000~51.015
51.050
Cylinder
Deformation -
0.100
-
0.100
ID: inner diameter
OD: outer diameter
Tighten torque value
Cylinder head
1.0 kgf-m
Exhaust pipe connection nut
1.2 kgf-m
Spark plug
1.4 kgf-m
Exhaust muffler mounting bolt
3.3 kgf-m
Troubleshooting
Compression Pressure Too Low/Difficult
To Start/Rough Idling
1. Cylinder head gasket leaking
2. Spark plug not tighten enough
3. Worn, seized or crack piston ring
4. Damaged, worn cylinder or piston
5. Poor reed
Compression Pressure Too
High/Overheat/Knock
1. Too much carbon deposit built up in
combustion chamber
Piston Noise
1. cylinder and piston worn out
2. piston pin or piston pin hole worn out
3. connecting rod small end bearing worn out
Piston Ring Noise
1. Worn, seized or crack piston ring
2. Cylinder worn out or damaged
Summary of Contents for Euro 100
Page 1: ...SERVICE MANUAL Forward Contents How To Use This Manual Mechanism Illustrations 50 100 50 100...
Page 7: ......
Page 25: ...1 GENERAL INFORMATION 1 18 Note This chapter Contents...
Page 45: ...3 LUBRICATION SYSTEM 3 6 NOTES This chapter Contents...
Page 81: ...8 FINAL DRIVING MECHANISM 8 6 Notes This chapter Contents...
Page 97: ...10 FUEL SYSTEM 10 10 Notes This chapter Contents...
Page 109: ...11 BRAKE SYSTEM 11 12 Notes This chapter Contents...
Page 121: ...12 BODY COVER 12 12 Note This chapter Contents...
Page 157: ...15 ELECTRICAL EQUIPMENT 15 22 Notes This chapter Contents...
Page 158: ...16 ELECTRICAL DIAGRAM 16 1 JET 50 ELECTRICAL DIAGRAM 16 Home page Contents...
Page 159: ...16 ELECTRICAL DIAGRAM 16 2 JET 50 EURO ELECTRICAL DIAGRAM Home page Contents...
Page 160: ...16 ELECTRICAL DIAGRAM 16 3 JET 100 ELECTRICAL DIAGRAM Home page Contents...
Page 161: ...16 ELECTRICAL DIAGRAM 16 4 Notes Home page Contents...