BMW R 4 series 5

BMW R 4 series 5 Date 1936 - 1937

Number sold 5.033

Price 1.150,- RM

Engine

internal designation M 69 S 5
engine type four-stroke two-cylinder flat-twin
Bore/stroke 84 x 78 mm
Cubic capacity 398 cm3
Max power 14 PS at 4000 U /min
Compression ratio 5,7 : 1
Valves per cylinder ohv
Carburation system 1 carburettor Typ SUM CK 3/500 Fr
Engine lubrication forced-feed lubrication
oil pump gear pump

 
Power transmission

Clutch single discs, dry
Number of gears 4
shifting manual (Tankkulisse)
Gear ratios 3,6 / 2,18 / 1,35 / 1,1
Rear wheel ratio 1 : 5,11 (with sidecar 1: 5,63)
Bevel/crown wheel 9 / 46 teeth (with sidecar (8 / 45)

 
Electrical system

Alternator Bosch, 45 W / 6 V
Ignition battery ignition
Spark plugs Bosch DM 175/1

 
Suspension

designation F 69 S 5
Type of frame pressed steel duplex frame
Front suspension plate spring, 9 laminae mit 2 Stoßdämpfern
Rear suspension rigid
wheel rims 26 x 3,5
Tyres front 26 x 3,5 SS
Tyres rear 26 x 3,5 SS
Brakes front drum brake Ø 180 mm
Brakes rear drum brake Ø 180 mm

 
Dimensions and weights

Length x width x height 1980 x 850 x 950 mm
Wheel base 1300 mm
Tank capacity 12 l
Unladen weight, full tank 137 kg
permitted loading 200 kg
Fuel consumption ca. 3,5 l / 100 km
oil consumption ca. 1 - 2 l / 1000 km
Top speed 100 km/h