R51


Production Model Years
   1938 - 1940

Frame and Engine Numbers

   Frame numbers
    505001 - 515164
    ———
   Engine numbers
    503001 - 506172

Model Specifications
Drivetrain
Displacement494cc
Cylinders2
Bore x Stroke (mm)68 x 68
HP @ RPM24 @ 5600
Compression Ratio6.7:1
ValvesOHV, 2 per cylinder
ClutchDry, single plate, cable operated
Transmission4 speed, foot shifted
Final DriveDriveshaft
Running Gear
FrameTubular steel double cradle
Front SuspensionHydraulically damped telescopic fork
Rear SuspensionPlunger
Front Brakes200mm drum, single leading shoe
Rear Brakes200mm drum, single leading shoe
Electrical
IgnitionBattery/coil
Spark PlugsBosch W225
GeneratorBosch RD 45/6 6V 45/70W (early) RD 50/6 6V 50/75W (late)
Capacities & Measurements
Weight182kg
Fuel14l
Wheelbase1400mm
Top Speed140kph
Number Produced3172

The information provided here was obtained from a variety of public sources and may not reflect official BMW archival data.
Please contact the BMW Archives for official data regarding models.