LONCIN G250F User Manual

Section 1 Safety and General Information
1.6 Maintenance standards
Unspecified unit : mm
Part
Item
Standard
Service Limit
G250F(D)S
Engine
Maximum speed（rpm/min）
3300±100
cylinder
Sleeve(inside diameter)
75
75.17
piston
skirt outside diameter
74.97
74.82
Clearance to cylinder
0.015-0.05
0.12
Piston pin bore inside diameter
18.002
18.048
piston – pin clearance
0.002-0.014
0.06
piston pin
Outside diameter
18
17.954
piston ring
side gap
0.015-0.045
0.15
close gap
(top ring)
0.2-0.4
1.0
close gap
(the second ring)
0.3-0.5
1.0
close gap
(oil ring)
0.2-0.7
1.0
Width (top ring)
1.0
0.87
Width ( second ring)
1.2
1.07
connecting rod
small end inside diameter
18.006~18.017
18.07
big end inside diameter
30. 22~30.233
30.274
big end side clearance
0.25-0.65
1.1
crankshaft
neck diameter
29.975-29.99
29.915
valve
Clearance(cold) (intake)
0.10-0.15
－
Clearance(cold) (exhaust)
0. 15-0.20
－
Stem diameter (intake)
5.468~5.48
5.318
Stem diameter (exhaust)
5.428~5.44
5.275
Valve guide
Inside diameter (intake, exhaust)
5.50~5.512
5.572
Stem to guide clearance (intake)
0.02-0.044
0.10
Stem to guide clearance exhaust)
0.06-0.084
0.12
Valve seat
Seat width
0.8
2.0
Valve spring
free length
34~35
32.5
Cam shaft
height (intake)
28.52
28.27
height (exhaust)
28.56
28.31
Outside diameter (bearing)
13.966~13.984
13.916
crankcase cover
Camshaft hole diameter
14.0~14.018
14.048
spark plug
gap
0.7-0.8
－
igniter coils
resistance (primary)
1.0-1.2Ω
－
resistance (secondary)
5.1-6.1Ω
－
gap to flywheel
0.35-0.45
－
1-7

LONCIN G250F Specifications

General

Brand	LONCIN
Model	G250F
Category	Engine
Language	English