Production Model Years
   1925 - 1926

Frame and Engine Numbers

   Frame numbers
    8000 - 8900
   Engine numbers
    36000 - 36900


Model Documentation


Model Specifications

Bore x Stroke (mm)68 x 68
HP @ RPM6.5 @ 4000
Compression Ratio6.0:1
ValvesOHV, 2 per cylinder
ClutchDry, single plate, cable operated
Transmission3 speed, hand shifted
Final DriveDriveshaft
Running Gear
FrameTubular double loop, brazed
Front SuspensionUndamped, trailing link, dual leaf spring
Rear SuspensionRigid
Front Brakes150mm drum, single leading shoe
Rear BrakesContracting shoes on driveshaft mounted drum, heel operated
IgnitionBosch magneto
Spark PlugsBosch W175
GeneratorBosch magneto/generator, G 6V
Capacities & Measurements
Top Speed100kph
Number Produced855
BMW's first single. In order to attract buyers at the lower end of the price scale, BMW introduced the R39 single. Unfortunately, design problems with the single piece upper crankcase half/cylinder, which was alloy and had a shrunk in iron liner, meant that BMW had to remove the bike from the market after a short run.

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.