BMW R 25

BMW R 25 Date 1950 - 1951

Number sold 23.400

Price 1.750,- DM

Engine

internal designation 224/2
engine type four-stroke two-cylinder flat-twin
Bore/stroke 68 x 68 mm
Cubic capacity 247 cm3
Max power 12 PS at 5600 U /min
Compression ratio 6,5 : 1
Valves per cylinder ohv
Carburation system 1 Bing type 1 / 22 / 28
Engine lubrication forced-feed lubrication
oil pump gear pump

 
Power transmission

Clutch single discs, dry
Number of gears 4
shifting foot shifting (+ auxiliary manual switch on gearing block)
Gear ratios 6,1 / 3,0 / 2,04 / 1,54
Rear wheel ratio 4,5 : 1 (with sidecar 5,14 : 1)
Bevel/crown wheel 6 / 27 teeth (with sidecar 7 : 36)

 
Electrical system

Alternator Noris 6 V / 45-60 W
Ignition battery ignition
Spark plugs Bosch DM 240 T 1or Bosch W 240 T 1 A

 
Suspension

designation 225/1
Type of frame closed steel twin-loop frame, welded
Front suspension telescopic fork
Rear suspension Geradwegfederung
wheel rims 3 x 19
Tyres front 3,25 x 19
Tyres rear 3,25 x 19
Brakes front drum brake 160 mm
Brakes rear drum brake 160 mm

 
Dimensions and weights

Length x width x height 2073 x 750 x 710 mm
Ground clearance 108 mm
Tank capacity 12 l
Unladen weight, full tank 140 kg
permitted loading 290 kg (with sidecar 365 kg)
Fuel consumption ca. 3,5 l / 100 km
oil consumption ca. 1 l / 1000 km
Top speed 95 km/h (with sidecar 80 km/h)