Historic Motorcycle Brands
In 1916, Danish engineer Jørgen Skafte Rasmussen founded a factory in Zschopau, Saxony, Germany, to produce steam fittings. His initial vehicle efforts were with steam, hence the company name Dampf Kraft Wagen (steam motor vehicle) DKW, but later switched to combustion engine power.
1921 DKW ‘Auxiliary Bicycle’ – Audi
DKW motorcycle history had a weird start that began with a two-stroke, 18cc, stationary-toy engine, designed by engineer, Hugo Ruppe, in 1919. Like steam ‘donkey’ engines that were universally popular with mechanically-inclined children, the DKW toy was a success.
In 1921, Rasmussen put a 118cc version of this engine into what was converted bicycle, called Das Kleine Wunder (the little wonder) so that the initials were ‘DKW’.
1921 Slaby-Beringer Elektrowagen – Frank C Muller
DKW production motorcycles began with the 1922, 142cc model and subsequent editions became instantly popular. By the late 1920s, DKW was the world’s largest motorcycle manufacturer.
In September 1924, DKW bought Slaby-Beringer, who had developed a small one-person car, powered by an electric motor. This revolutionary development had a self-supporting body made of triplex plastic and was specially designed for war invalids who, however, usually did not have the necessary money for a vehicle.
Rudolf Slaby became chief engineer at DKW.
1927 DKW E206 – Lothar Spurzem
To improve the performance of its racing two-strokes, DKW tried several designs, including Ruppe’s ‘dummy piston’ designed that effectively supercharged crankcase induction. However, this designed retained a ‘deflector’ piston crown that didn’t result in an optimal combustion chamber shape.
DKW thought the porting design newly-developed by Adolf Schnurle was the way to go, thanks to its flat-top piston, but needed some supercharging effect as well. The company went for a ‘split piston’ design that had been around since 1912 and was further developed by DKW’s Arnold Zoller in 1931.
Previous split-piston two-strokes had synchronous, paired pistons sharing a common combustion chamber. One piston had induction porting and the other, exhaust.
Zoller’s combination of Schnurle porting and split-piston design used ‘timed’ pistons, with different strokes. In operation, the exhaust piston closed off its ports while the intakes ports still open, thus producing a supercharging effect.
That supercharging effect was done, initially, by a third piston either externally mounted or Ruppe-style, inside the crankcase. The final version had an engine driven, centrifugal supercharger.
1938 DKW SS 250 – Lothar Spurzem
The first Zoller racing engine was a split-twin 248cc, with a third, external supercharging piston. It was good for 24hp at launch and that increased to 30hp. Later models had increased engine capacity, up to 350cc and 48hp.
This engine design made DKW the dominant racing motorcycle in the Lightweight and Junior classes between the World Wars.
Racing success included off-road events, including the International Six Days Trial, where the marque scored considerable inter-War-year successes. Ewald Kluge’s victory in the 1938 Isle of Man Lightweight TT, at an average 78.48mph, was the first IoM win by a German rider.
1930 DKW Super Sport 500 – Matej Batha
In 1932, to help combat the Great Depression, DKW merged with Audi, Horch and Wanderer to form Auto Union.
One of the most famous DKW models was the RT 125 that was produced pre- , during- and post-World War II.
DKW NZ350 – LynneF
During Wold War II, DKW provided the German military with one of its most popular motorcycle types, the NZ350. Of conventional design, the model was powered by a single-cylinder, 346cc, two-stroke engine that provided a road speed of 62mph. It primarily served in the dispatch role and was noted for its cross-country capabilities.
After World War II, DKW moved to West Germany and the original factory in GDR became MZ, producing 175, 250 and 350 models. MZ models continued in production until the 1990s, when production of the two-stroke came to an end.
1950 DKW RT125W – Huhu
As part of the World War II reparations, the design drawings of the RT125 were given to Harley-Davidson in the US and BSA in the UK. The Harley-Davidson version was known loosely as the Hummer and BSA called its version the Bantam.
It’s also pretty clear that Yamaha ‘reverse-engineered’ the DKW engine in the 1950s.
1952 DKW RT200
The first post-War DKW RT125 were built in 1949. Rear suspension and telescopic front forks were later added and the model range grew to include a 350cc twin. Hobby and Luxus scooters joined the range in 1954 and continued until 1957.
1953 DKW RM 350 – Lothar Spurzem
The VS motorcycle range of RT175, 200 and 250 featured Earles-type front forks, but didn’t sell well. Effectively, DKW motorcycle production ended in 1959, although moped manufacture continued.