Information kindly supplied by P.Hawksley

www.bmbikes.co.uk

Start of Production

1930

Click to View Available Literature

End of Production

1931

Number Produced:

7,500 (All Series)

Price:

1.750 RM

Engine

 

Internal Designation

M 56 S 2

Motor Type

Four Stroke two cylinder flat twin

Bore x Stroke

78 x 78 mm (3.07 x 3.07 in)

Displacement

745 cc

Maximum Power

18 hp at 3,400 rpm

Compression Ratio

5.5 : 1

Valves

Side Valve

Carburation System

Single carb. Type BMW 24 mm

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

2.83 / 1.55 / 1.08

Rear Wheel Ratio

1 : 4.07  (1 : 4.75 with sidecar)

Bevel / Crownwheel

14 / 57  (12 / 57 with sidecar)



Electrical System

 

Ignition System

Magneto ignition

Generator

Bosch Magneto generator D2L or Magneto Ignition FF2

Spark Plugs

Bosch W 175 T1






Chassis

 

Designation

F 66 S 2

Frame

Twin loop pressed steel frame

Front Suspension

Plate spring 9 laminae

Rear Suspension

Rigid

Wheel Rims

26 x 3.5 safety rims

Front Tyre

26 x 3.5 low pressure or 26 x 3.25 high pressure

Rear Tyre

26 x 3.5 low pressure or 26 x 3.25 high pressure

Front Brakes

Drum brake 200 mm / 7.87 in diameter

Rear Brake

Cardan brake, 55 mm / 2.16 in width




Dimensions/Weights

 

Length x Width x Height

2100 x 890 x 940 mm (82.67 x 35.03 x 37 in)

Wheel Base

1380 mm / 54.33 in

Fuel Tank Capacity

14 litres / 3.07 gal / 3.69 gal US

Unladen Weight with full tank

162 kg / 356 lb

Load Rating

210 kg / 462 lb

Fuel Consumption per 1,00 kilometres

4 - 4.5 litres approx / 70 - 62 mpg / 58 - 52 mpg US

Oil Consumption

1 - 2 litres per 1,000 kilometres

Top Speed

95 - 100 kph / 59 - 62 mph