68 TECHNICAL DATA
Engine:
Ignition:
360cc
SOlce
12:1
Two-stroke. single
-:::isplacement:
Compression
ratio:
ruel:
Lubrication:
cylinder
engine
250cc
~OOcc
247cc
386cc
12,3:1
12:1
Regular petrol
Petroleum type racing oil,
e.g. Castrol GP 50 wt. mixing
ratio of
20:1 (5\)
Appt. magneto separate high-tension coil.
Timing: 250=2.98TDC, 400=3.6 BTDC,
501=3.6 BTDC
Contact breaker gap: .014-.018"(0.35-0.45)
Spark plug: Champion L3G=250, L2G=400,
N2G=501
Frame:
Power transmission:
Oil-damped telescopic fork. 7 inches
movement. Oil capacity: 60z (0.2 litre)
per fork leg. Oil recommendation: Engine
oil SAE 20-50 depending on temperature,
rider and course.
Frame
is
welded chromemolybdenum steel.
Pivoting rear arm in rubber bushings.
front: 3.0OX 21" with moto •.cross tyre.
Rear: 4.0OxlS" with moto-cross tyre for 250
4.SOX18" with moto-cross tyre for 400&501
Wheels:
Front fork:
400 - l3T front -
52! rear
250 - 11T front - 52T rear
501 - l3T front - 52T rear
400 -
l3T front - 59T
rear
250 - 11T front
-
59T
rear
501 - l3T front
-
59T
rear
;earbox:
Seven disc mote-cross type clutch.
Primary transmission
by
dual row primary
chain 19T x
39r
(1.86 to 1)
-Secondary transmission
by
chain drive
5/8"
x
114
ft).
12 teeth
on gearbox sprocket
]nd 53 teeth on rear wheel.
"SII Transmission
T" Transmission
Transmission
4-Speed Heavy Duty
"Til
"S"
Brakes:
1st
2nd
3rd
4th
Mota Cross
1.99 to 1
1. 52
1. 23
1.0
Cross Country
2.78
to
1
1.79
1.29
1.0
rear: diam. 160x30 mm (6 5/16
11
xl 3/16")
front: diam. 14Ox30 mm (5 1/2"xl 3/16")
Saddle:
Oil
capacity:
1
quart
-;11
recommendation: Transmission oil SAE 40wt.
for 2S0, SAE 90wt. gear
oil for 400
&
501.
Moto-cross type.
Footrests:
FOlding footrests at a 45° angle.
;arhurettor:
250
400
501
Moto-eross type with paper element.
~ir filter:
listen
&
Flywheel data:
Wheelbase: 54" (1315
1mI)
Saddle height: 31.5" (SOO
rrrn)
Ground clearance: 7" (180 mm)
Dry weight: 250cc: 102 kg (224 lb.)
400cC: 105 kg (231 lb.)
50lcc: 107 kg (239 lb.)
Fiberglass fuel tank
Capacity: 7 liter (1.9 Gals)
rueltank:
Dimensions:
180
35
280
3
1 1/2
185
35
285
3
1 1/2
1/36/101
180
35
280
3
1 1/2
Jing:
Main jet:
.dling jet:
leedle jet:
leedle position:
Air screw opening:
Flywheel assembly.
Side play of connecting
-rod shall be .019-.020. Replace .023 or
;reater.
listance across flywheels outside to outside
2.475. Reference only.
Run out when supported on bearing area ,
-leasured at extreme end of magneto taper
.hall not exceed .002 inch •
•'iming side bearing - up
&
down play .010
inch max.
~iston ring end gap - .003 per inch of
iameter.
~ylinder sleeve to cylinder new .013
interference when replacing turn sleeve
-.0 -
.004-.006 interference.
iston to cylinder clearance .002 inch
or 250 & 400. 501 shall be .0025 inch.
Screwed joints:
Nut for magneto: 10 lb.ft. (1.7kpm)
Nut for output chainsprocket:50 Ib.ft.(7kpm)
Nuts which hold the cylinder head to the
cylinder: 15 lb.ft.(2.5kpm) for 250
&
400;
25 lb.ft. 13.5kpm) for 501
Engine mounting bolts:25 lb.ft.{3.Skpm) Bmm bolts
35 lb.ft. (5.2kpm) for 10m bolts
Nuts which hold the bearing bolts for the rear
wheel
pivot arm: 25 Ib.ft. (3.5kpm)
Clutch nut • 30 foot lbs.
Engine sprocket nut. 35-45 foot Ibs.
Counter shaft nut - 40-50 foot lbs.
68 TECHNICAL DATA
Engine:
Ignition:
360cc
SOlce
12:1
Two-stroke. single
-:::isplacement:
Compression
ratio:
ruel:
Lubrication:
cylinder
engine
250cc
~OOcc
247cc
386cc
12,3:1
12:1
Regular petrol
Petroleum type racing oil,
e.g. Castrol GP 50 wt. mixing
ratio of
20:1 (5\)
Appt. magneto separate high-tension coil.
Timing: 250=2.98TDC, 400=3.6 BTDC,
501=3.6 BTDC
Contact breaker gap: .014-.018"(0.35-0.45)
Spark plug: Champion L3G=250, L2G=400,
N2G=501
Frame:
Power transmission:
Oil-damped telescopic fork. 7 inches
movement. Oil capacity: 60z (0.2 litre)
per fork leg. Oil recommendation: Engine
oil SAE 20-50 depending on temperature,
rider and course.
Frame
is
welded chromemolybdenum steel.
Pivoting rear arm in rubber bushings.
front: 3.0OX 21" with moto •.cross tyre.
Rear: 4.0OxlS" with moto-cross tyre for 250
4.SOX18" with moto-cross tyre for 400&501
Wheels:
Front fork:
400 - l3T front -
52! rear
250 - 11T front - 52T rear
501 - l3T front - 52T rear
400 -
l3T front - 59T
rear
250 - 11T front
-
59T
rear
501 - l3T front
-
59T
rear
;earbox:
Seven disc mote-cross type clutch.
Primary transmission
by
dual row primary
chain 19T x
39r
(1.86 to 1)
-Secondary transmission
by
chain drive
5/8"
x
114
ft).
12 teeth
on gearbox sprocket
]nd 53 teeth on rear wheel.
"SII Transmission
T" Transmission
Transmission
4-Speed Heavy Duty
"Til
"S"
Brakes:
1st
2nd
3rd
4th
Mota Cross
1.99 to 1
1. 52
1. 23
1.0
Cross Country
2.78
to
1
1.79
1.29
1.0
rear: diam. 160x30 mm (6 5/16
11
xl 3/16")
front: diam. 14Ox30 mm (5 1/2"xl 3/16")
Saddle:
Oil
capacity:
1
quart
-;11
recommendation: Transmission oil SAE 40wt.
for 2S0, SAE 90wt. gear
oil for 400
&
501.
Moto-cross type.
Footrests:
FOlding footrests at a 45° angle.
;arhurettor:
250
400
501
Moto-eross type with paper element.
~ir filter:
listen
&
Flywheel data:
Wheelbase: 54" (1315
1mI)
Saddle height: 31.5" (SOO
rrrn)
Ground clearance: 7" (180 mm)
Dry weight: 250cc: 102 kg (224 lb.)
400cC: 105 kg (231 lb.)
50lcc: 107 kg (239 lb.)
Fiberglass fuel tank
Capacity: 7 liter (1.9 Gals)
rueltank:
Dimensions:
180
35
280
3
1 1/2
185
35
285
3
1 1/2
1/36/101
180
35
280
3
1 1/2
Jing:
Main jet:
.dling jet:
leedle jet:
leedle position:
Air screw opening:
Flywheel assembly.
Side play of connecting
-rod shall be .019-.020. Replace .023 or
;reater.
listance across flywheels outside to outside
2.475. Reference only.
Run out when supported on bearing area ,
-leasured at extreme end of magneto taper
.hall not exceed .002 inch •
•'iming side bearing - up
&
down play .010
inch max.
~iston ring end gap - .003 per inch of
iameter.
~ylinder sleeve to cylinder new .013
interference when replacing turn sleeve
-.0 -
.004-.006 interference.
iston to cylinder clearance .002 inch
or 250 & 400. 501 shall be .0025 inch.
Screwed joints:
Nut for magneto: 10 lb.ft. (1.7kpm)
Nut for output chainsprocket:50 Ib.ft.(7kpm)
Nuts which hold the cylinder head to the
cylinder: 15 lb.ft.(2.5kpm) for 250
&
400;
25 lb.ft. 13.5kpm) for 501
Engine mounting bolts:25 lb.ft.{3.Skpm) Bmm bolts
35 lb.ft. (5.2kpm) for 10m bolts
Nuts which hold the bearing bolts for the rear
wheel
pivot arm: 25 Ib.ft. (3.5kpm)
Clutch nut • 30 foot lbs.
Engine sprocket nut. 35-45 foot Ibs.
Counter shaft nut - 40-50 foot lbs.
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Square Barrel Engine Manual Service Manual
