Part I Introduction
3
1-3 Service standards
Gasoline engine
Part
Item
Standard
Service limit
Gasoline engine
Maximum no-load speed
Cylinder pressure
3180-3800 rpm
1.25MPa/1400rpm
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Cylinder
Cylinder bore diameter
82mm
82.195mm
Cylinder head
cover
Warping
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0.10mm
Piston
Outer diameter of piston skirt
Piston-cylinder clearance
Inner diameter of piston pinhole
Outer diameter of piston pin
Piston pin-piston pinhole clearance
81.962~81.98mm
0.02~0.058mm
17.004~17.01mm
16.992~16.998mm
0.006~0.018mm
81.86mm
0.12mm
17.048mm
16.954mm
0.08mm
Piston ring
Piston ring side clearance: top ring/ring 2
Oil ring
Piston ring closing clearance: top ring/ring 2
Oil ring
Piston ring width: top ring/ring 2/oil ring
0.03~0.05/0.02~0.04mm
0.04~0.11mm
0.2~0.35/0.35~0.5mm
0.2~0.7mm
1.17~1.19mm
1.91~1.97mm
0.135mm
0.31mm
1.0mm
1.5mm
0.77mm
1.46mm
Connecting rod
Inner diameter of small end
Inner diameter of big end
Big end oil film clearance
Small end side clearance
17.005~17.016mm
40.01~40.022mm
0.03~0.054mm
0.2~0.6mm
17.052mm
40.066mm
0.12mm
1.0mm
Crankshaft
Outer diameter of main journal
39.968~39.98mm
39.92mm
Air valve
Valve clearance
Outer diameter of valve
stem
Conduit inner diameter
Tappet clearance
Valve seat contact width
Free length of spring
Intake
Exhaust
Intake
Exhaust
Intake/exhaust
Intake
Exhaust
0.1~0.15mm
0.15~0.2mm
6.466~6.475mm
6.451~6.46mm
6.5~6.515mm
0.025~0.049mm
0.04~0.064mm
0.7~1.0mm
39.4mm
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6.318mm
6.275mm
6.562mm
0.10mm
0.12mm
2.0mm
38mm
Camshaft
Cam height Intake
Exhaust
Outer diameter of journal
4.64~4.80mm
4.64~4.80mm
15.959~15.977mm
4.35mm
4.35mm
15.916mm
Crankcase cover Inner diameter of camshaft bore
16~16.018mm
16.048mm
Carburetor
Float height
13.2mm
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Spark plug
Clearance
0.7~0.8mm
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Spark plug cap
Resistance
9~11kΩ
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Ignition coil
Resistance
Ignition coil clearance
Primary side
Secondary side
0.8-1.0Ω
5.9-7.1kΩ
0.35~0.45mm
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