BMW R 63

The first OHV opposed-twin 750cc BMW motorcycle: the 1928/1929 R63. In 1929, Ernst Henne's first motorcycle world speed record of 133.8 MPH (215 km/h) was set on an R63 fitted with a supercharger. However, the stock R63 was conservatively rated for a 75 MPH (120 km/h) top speed. In January 2002, the restored 1928 R63 shown below sold at auction in Las Vegas for $30,000.


BMW R 63
  Date 1928-1929

  Number sold 794

  Price 2,100.- RM

Engine

internal designation M 60
engine type four-stroke two-cylinder flat-twin
Bore/stroke 83 x 68 mm
Cubic capacity 735 cm3
Max power 24 PS at 4000 U /min
Compression ratio 6,2 : 1
Valves per cylinder ohv
Carburation system 1 carburettor, Typ BMW Spezial two-valve 24 mm
Engine lubrication forced-feed lubrication
oil pump gear pump

 
Power transmission

 
Clutch single discs, dry - from engine no. 75845: two discs
Number of gears 3
shifting manual
Gear ratios 2,83 / 1,55 / 1,08
Rear wheel ratio 1 : 4,07 (sidecar 1 : 4,75)
Bevel/crown wheel 14 / 57 teeth (sidecar 12 / 57)

 
Electrical system

Alternator magneto generator on request Bosch
Ignition Bosch high-voltage magneto ignition
Spark plugs Bosch W 175 or W 200

 
Suspension

designation F 56
Type of frame twin-loop steel tubular frame
Front suspension plate spring, 6 laminae
Rear suspension rigid
wheel rims deep-bed 19 x 3 or 21 x 2,5
Tyres front 26 x 3,5 on 19 x 3 or 27 x 2,75 on 21 x 2,5
Tyres rear 26 x 3,5 on 19 x 3 or 27 x 2,75 on 21 x 2,5
Brakes front drum brake Ø 200 mm
Brakes rear external shoe brake at gearing (on cardan shaft)

 
Dimensions and weights

Length x width x height 2100 x 800 x 950 mm
Wheel base 1400 mm
Tank capacity 12,5 l
Unladen weight, full tank 152 kg
load rating 210 kg
Fuel consumption ca. 5 l / 100 km
oil consumption ca. 1 - 2 l / 1000 km
Top speed 120 km/h