- For the 1970s 750 cc motorcycle see BMW R75/5
The
BMW R75 is a
World War IIWorld War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
-era
motorcycleA motorcycle is a single-track, two-wheeled motor vehicle. Motorcycles vary considerably depending on the task for which they are designed, such as long distance travel, navigating congested urban traffic, cruising, sport and racing, or off-road conditions.Motorcycles are one of the most...
and
sidecarA sidecar is a one-wheeled device attached to the side of a motorcycle, scooter, or bicycle, producing a three-wheeled vehicle.-History:A sidecar appeared in a cartoon by George Moore in the January 7, 1903, issue of the British newspaper Motor Cycling. Three weeks later, a provisional patent was...
combination produced by the German company
BMWBayerische Motoren Werke AG is a German automobile, motorcycle and engine manufacturing company founded in 1916. It also owns and produces the Mini marque, and is the parent company of Rolls-Royce Motor Cars. BMW produces motorcycles under BMW Motorrad and Husqvarna brands...
.
In the 1930s BMW were producing a number of popular and highly effective motorcycles. In 1938 development of the R75 started in response to a request from the German Army.
Preproduction models of the R75 were powered by a 750 cc side valve engine, which was based on the proven R12 engine. However it was quickly found necessary to design an all new OHV 750 cc engine for the R75 unit. This OHV engine later proved to be the basis for subsequent post-war twin BMW engines like the R51/3, R67 and R68.
The third side-car wheel was driven with an axle connected to the rear wheel of the motorcycle, effectively making it a
three-wheeled vehicleA tricycle is a three-wheeled vehicle. While tricycles are often associated with the small three-wheeled vehicles used by pre-school-age children, they are also used by adults for a variety of purposes. In the United States and Canada, adult-sized tricycles are used primarily by older persons for...
. These were fitted with a
locking differentialA locking differential, diff-lock or locker is a variation on the standard automotive differential. A locking differential may provide increased traction compared to a standard, or "open" differential by restricting each of the two wheels on an axle to the same rotational speed without regard to...
and selectable road and off-road
gear ratioThe gear ratio of a gear train is the ratio of the angular velocity of the input gear to the angular velocity of the output gear, also known as the speed ratio of the gear train. The gear ratio can be computed directly from the numbers of teeth of the various gears that engage to form the gear...
s through which all four and reverse gears worked. This made the R75 highly manoeuvrable and capable of negotiating most surfaces. A few other motorcycle manufactures, like FN and Norton, provided an optional drive to sidecars but with very limited success.
The BMW and its rival
ZündappZündapp was a major German motorcycle manufacturer. The company was founded in 1917 in Nuremberg by Fritz Neumeyer, together with the Friedrich Krupp AG and the machine tool manufacturer Thiel under the name "Zünder- und Apparatebau G.m.b.H." as a producer of detonators...
were both widely used by the
WehrmachtThe Wehrmacht – from , to defend and , the might/power) were the unified armed forces of Nazi Germany from 1935 to 1945. It consisted of the Heer , the Kriegsmarine and the Luftwaffe .-Origin and use of the term:...
in the
Eastern FrontThe Eastern Front of World War II was a theatre of World War II between the European Axis powers and co-belligerent Finland against the Soviet Union, Poland, and some other Allies which encompassed Northern, Southern and Eastern Europe from 22 June 1941 to 9 May 1945...
and
North African CampaignDuring the Second World War, the North African Campaign took place in North Africa from 10 June 1940 to 13 May 1943. It included campaigns fought in the Libyan and Egyptian deserts and in Morocco and Algeria and Tunisia .The campaign was fought between the Allies and Axis powers, many of whom had...
.
Zündapp and BMW, on the urging of the Army, agreed upon standardisation of parts for both machines. The standardisation programme meant that machines that were produced by BMW and Zündapp used almost 70% of the same components.
This simplifies the supply of spare parts for these vehicles, many of which are still in the hands of historic motorcycle enthusiasts. These vehicles are desirable as collector's items because of their complex and durable technology. A well-restored R75 can be still used for everyday purposes, on or off-road without problems.
In 1954 a small number of modified R75 models were produced at Eisenach (then in Soviet-controlled East Germany) for testing under the designation AWO 700, but were not put into full production.
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