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BMW R25 Specifications

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Start of Production

1950

BMW R25

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End of Production

1951

Numbers Produced

23,400

Price

1,750 DM

Engine

 

Internal Designation

224/2

Motor Type

Four-stroke single cylinder vertical

Bore x Stroke

68 x 68 mm (2.67 x 2.67 in)

Displacement

247 cc

Max Power

12 hp at 5,600 rpm

Compression Ratio

6.5 : 1

Valves

OHV

Carburation System

1 x Bing type 1/22/28

Engine Lubricating System

Forced feed lubrication

Oil Pump

Gear pump

Power Transmission

 

Clutch

Single plate, dry

Number of Gears

4

Shifting

Foot switching (+ auxiliary manual switch on gearing block)

Gearbox Ratios

6.1 / 3.0 / 2.04 / 1.54

Rear Wheel Ratio

4.5 : 1 (with sidecar 5.14 : 1)

Bevel/Crownwheel

6 / 27 teeth (with sidecar 7 / 36)

Electrical System

 

Ignition System

Battery ignition

Generator

Bosch 6V/45-60W

Spark Plugs

Bosch W 240 T1 or Bosch W 240 T1 A

Chassis

 

Designation

225/1

Frame

Closed steel twin loop frame, bolted

Front wheel suspension

Telescopic fork

Rear wheel suspension

Pushrod suspension

Wheel rims

3 x 19 deep bed

Tyres, Front

3.25 x 19

Tyres, Rear

3.25 x 19

Brakes, Front

Drum brake 160 mm / 6.29 in diameter

Brakes, Rear

Drum brake 160 mm / 6.29 in diameter

Dimensions/Weights

 

Length x Width x Height

2073 x 750 x 710 mm (81.61 x 29.52 x 27.95 in)

Fuel Tank Capacity

12 litres / 2.63 gal / 3.17 gal US

Unladen Weight with Full Tank

140 Kg / 308 lb

Permitted Weight Limit

290 Kg / 290 lb (with sidecar 365 Kg / 803 lb)

Clearance

108 mm / 4.25 in

Fuel Consumption

Approx. 3.5 litres per 100 Km / 80 mpg / 67 mpg US

Oil Consumption

Approx. 1 litres per 1,000 Km

Top Speed

95 Kph  / 59 mph (with original sidecar 80 Kph / 49 mph)