Start of Production

1932

Click to View Available Literature

End of Production

1932

Number Produced:

1,101

Price:

1,250 RM

Engine


Internal Designation

M 69 S 1

Motor Type

Four Stroke single cylinder vertical

Bore x Stroke

84 x 78 mm (3.30 x 3.07 in)

Displacement

398 cc

Maximum Power

12hp at 4,000 rpm

Compression Ratio

5.7 : 1

Valves

OHV

Carburation System

1 x carburettor type SUM CK 3/500 Fr

Engine Lubricating System

Forced Feed Lubrication

Oil Pump

Gear Pump



Power Transmission


Clutch

Single plate dry clutch

Number of Gears

3

Gear Shift

Manual

Gearbox Ratios

2.9 / 1.5 / 1

Rear Wheel Ratio

1 : 5.11 (1 : 5.63 with sidecar)

Bevel / Crownwheel

9 / 46 teeth (8 / 45 with sidecar)



Electrical System


Ignition System

Battery ignition

Generator

Bosch 6V/30W

Spark Plugs

Bosch DM 175/1






Chassis


Designation

F 69 S 1

Frame

Pressed steel duplex frame

Front Suspension

Plate spring, 9 laminae, from July with friction shock absorber

Rear Suspension

Rigid

Wheel Rims

26 x 3.5

Front Tyre

26 x 3.5 SS

Rear Tyre

26 x 3.5 SS

Front Brakes

Drum brake 180 mm / 7.08 in diameter

Rear Brake

Drum brake 180 mm / 7.08 in diameter




Dimensions/Weights


Length x Width x Height

1980 x 850 x 950 mm (77.95 x 33.46 x 37.40 in)

Wheel Base

1300 mm / 5.11 in

Fuel Tank Capacity

10 litres / 2.19 gal / 2.64 gal US

Unladen Weight with full tank

137 kg / 301 lb

Permitted Weight Limit

200 kg / 440 lb

Fuel Consumption

3.5 litres per 100 kilometres approx / 80 mpg / 67 mpg US

Oil Consumption

1 - 2 litres per 1,000 kilometres

Top Speed

100  kph / 62 mph

Information kindly supplied by P.Hawksley

www.bmbikes.co.uk