Intro

C70 dimensions, torque specifications, model history and more.

Specifications

Honda C70 Specifications
English
Metric
Dimensions Overall Length
71.1 in.
1805 mm
Overall Width
26.2 in.
685 mm
Overall Height
39.2 in.
995 mm
Wheelbase
46.5 in.
1180 mm
Seat Height
29.9 in.
760 mm
Min. Ground Clearance
5.1 in.
130 mm
Dry Weight
184 lbs.
83.5 kg
Frame Type Pressed & tube steel type
F suspension, travel Leading link, travel 2.2 in. (55 mm)
R suspension, travel Swing arm, travel 2.4 in. (60 mm)
F tire size, pressure 2.25x17-4PR, 28 psi 2.25x17-4PR, 2.0 kg/cm2
R tire size, pressure 2.50x17-6PR, 28 psi (40 psi when laden) 2.50x17-6PR, 2.0 kg/cm2 (2.8 when laden)
F brake, lining area Cable, Internal expanding shoes, area 13.4 sq-in. (86.4 sq-cm)
R brake, lining area Rod, Internal expanding shoes, area 13.4 sq-in. (86.4 sq-cm)
Fuel capacity
1.05 US gal./4.0 l.
Fuel reserve capacity
0.21 US gal./0.8 l.
Caster angle 64 deg.
Trail length
2.8 in./ 70 mm
Engine Type Air cooled, 4 stroke OHC engine
Cylinder arrangement Single cylinder 80 deg inclined from vertical
Bore and stroke 1.850 x 1.630 in. 47.0 x 41.4 mm
Displacement 4.4 cu-in. 72cc
Compression Ratio 8.8 : 1
Valve train Chain driven overhead camshaft
Maximum horsepower
5.0 BHP at 7000 rpm
Maximum torque 3.9 lb/ft at 5500 rpm 0.56 kg-m at 5500 rpm
Oil capacity
0.74 US qt.
0.7 l
Lubrication system Forced and wet sump
Cylinder head compression pressure 178 +/-7 psi at 1000 rpm 12.5 +/-0.5 kg/cm2 at 1000 rpm
Intake valve opens 0 deg BTDC
Intake valve closes 20 deg ABDC
Exhaust valve opens 25 deg BBDC
Exhaust valve closes 5 deg ATDC
Valve tappet clearance
IN-EX 0.0002 in.
IN-EX 0.05mm
Idle speed 1500 +/-100 rpm
Carburation Carburettor Type Piston valve (slide), 14mm (0.55") venturi bore
ID. Number 1980 model: PB32A 1981 model: PB32C
Float Level
0.42"
10.7mm
Drive Train Clutch Wet, multi plate, semi-auto centrifugal type
Transmisson 3 speed constant mesh
Primary reduction 4.058
Gear Ratio 1 3.272
Gear Ratio 2 1.722
Gear Ratio 3 1.190
Final reduction 2.571, drive sprocket XXT, driven sprocket XXT
Gear shift pattern Left foot operated return system, N-1-2-3
Electrical Ignition Flywheel magneto
Points Gap
0.012 - 0.016"
0.3 - 0.4 mm
Ignition Timing "F" Mark
15o BTDC, Static
Advance Start 1875 rpm
Full Advance
30o BTDC, at 2900 rpm
Starting System Kick starter and/or starter motor
Generator Flywheel AC generator, 57W at 5000 rpm
Battery Capacity 6 V, 11 Ah
Spark plug (normal) NGK C7HS or ND U22FS
Spark plug (cold climates) NGK C6H or ND U20FS
Spark plug (high speeds) NGK C9H or ND U24FB
Spark Plug Gap 0.024 - 0.028" / 0.6 - 0.7 mm
Fuse Capacity 10 A

Torque Specifications

Torque Specifications
Torque
Item
Quantity
Thread dia. (mm)
kg-m
ft-lb
Engine Cylinder Head Cover
4
6
0.9 - 1.2
7 - 9
Camshaft Sprocket
3
5
0.5 - 0.9
4 - 7
Clutch Locknut
1
14
3.8 - 4.5
28 - 33
Final Drive Sprocket
2
6
1.0 - 1.4
7 - 10
Flywheel
1
10
5.5 - 6.5
40 - 47
Spark Advancer
1
6
0.9 - 1.2
7 - 9
Frame Steering Stem Nut
1
22
6. 0 - 9.0
43 - 65
Handlebar Setting Nut
2
8
2.0 - 3.0
14 - 22
Steering Lock
2
6
0.6 -1.3
4 - 9
Front Axle Nut
1
10
3.0 - 4.0
22 - 29
Engine Hanger Bolt
2
8
2.5 - 3.5
18 - 25
Rear Axle Nut
1
12
4. 0 - 5.0
29 - 36
Final Driven sprocket
4
8
2.0 - 2.5
14 - 18
Rear Brake Torque Link
2
8
1.0 - 2.0
7 - 14
Rear Shock Absorber
4
10
2.0 - 3.0
14 - 22
Foot Peg
4
8
2.0 - 2.5
14 - 18
Swing Arm Pivot Bolt
1
10
3.0 - 4.0
22 - 29
Front Suspension Pivot Bolt
2
8
1.0 - 2.0
7 - 14
Front Suspension Pivot Bolt
2
8
2.0 - 3.0
14 - 22
Front Shock Absorber Upper Bolt
2
8
2.5 - 3.5
18 - 25
Front Turn Signal Stay
4
0.35 - 0.5
2.5 - 3.6
General 5 mm bolt/nut
0.45 - 0.6
3.3 - 4.3
6 mm bolt/nut
0.8 - 1.2
6 - 9
8 mm bolt/nut
1.8 - 2.5
13 - 18
10 mm bolt/nut
3.0 - 4.0
22 - 29
12mm bolt/nut
5.0 - 6.0
36 - 43
5 mm screw
0.35 - 0.5
2.5 - 3.6
6 mm screw
0.7 - 1.1
5 - 8
6 mm flange bolt/nut
1.0 - 1.4
7 - 10
8 mm flange bolt/nut
2.4 - 3.0
17 - 22
10 mm flange bolt/nut
3.0 - 4.0
22 - 29

Manuals

These will open as PDFs

Parts Catalog  Service Manual