1931 DKW R1000 Stationary Engine

In 1919, Jorge Rasmussen and Hugo Ruppe began showcasing an 18cc 'toy' stationary motor nicknamed "the boy's wish" at industrial shows. Often described as a toy motor, there was scarcely a market for such an expensive frivolity in post-Great War Germany. The true purpose of this first 'DKW' was as a demonstrator stationary motor targeting the small business market.

In the years before the Second World War, DKW would become the world's biggest motorcycle company as well as a major German automobile manufacturer, but a gigantic part of the company's business was stationary and industrial engines. These ranged from small, air-cooled single cylinder two-stroke engines to eight cylinder four-stroke engines, air-cooled and water-cooled, for use in cars, tractors, mowers, draisons, boats, water-pumps, fire-hoses, sprayers, electrical generators, in two-stroke, four-stroke and diesel format.


The stationary motor division of DKW was actually at the forefront of engine development, trialing every possible format. In 1931 they presented a four-cylinder inline water-cooled two-stroke motor, designated the RVW. The engine came in 1000cc and 1200cc capacity, with the 1200cc version generating 29 PS. Sales however proved to be very disappointing and only 100 engines were built, serial numbers 299001 to 299100. The engine was still being advertised in the 1933 brochure above.

Given the small production numbers, survivors are few. A complete example is held in a German museum collection (see postcard at the top of the post). A second example was discovered by Roland Servais in a Belgian scrap yard. Serial number 299035 was largely intact but some parts were missing.




Roland restored the motor and mounted it on a steel chassis and connected it to a French dynamo built by "Ateliers de Constructions Electriques de Lyon et Dauphiné" around 1925. You can see the engine in action in the video below:

Roland has decided it's time to pass the engine to a new custodian, so if you are interested in purchasing this extremely rare piece of DKW history, you can contact him here: rolandser@gmail.com
The engine is located in Belgium. Roland has other stationary motors too.

So why did DKW abandon development of the four-cylinder two-stoke? This is an interesting question, given that in a few years time DKW would come to recognize that the 600cc and 700cc twin-cylinder had reached its developmental limits and would begin scrambling to develop a new engine for their automotive range. They would, of course, settle on the 900cc triple, which in its initial configuration generated approximately 26 PS. In the RVW engine they had a motor that could generate at least 29 PS. It cannot be that this format engine wasn't suitable for an automobile engine because a remarkably similar engine was powering a range of Czechoslovak cars at roughly the same time - and this is where the story becomes intriguing.

Zbrojovka Brno was a Czech armaments manufacturer that branched out into automobiles in the mid-1920s. After developing their own series of two-stroke budget cars, in 1932 they sought to enter a licensing partnership with DKW. Two engineers were dispatched to Zwickau to work on the project, but DKW's licensing fees were too high for Zbrojovka and they walked away from the deals. The engineers however had learned enough from their time in Zwickau to design their own car from scratch in a period of only 9 months. This would be the Zbrojovka Z-4 ("Strong Four"), which went on sale in January 1933. The Z-4 was powered by a four-cylinder water-cooled two-stroke motor of 908cc, generating 16 PS. Later series were upgraded to 980cc capacity. The engine is strikingly similar to the DKW RVW, so it seems entirely possible to me that Zbrojovka's engineers had inspected the RVW engine in detail, or purchased one and reverse engineered it. Of course, this is only speculation but it's a plausible theory. Zbrojovka also used twin-cylinder two-stroke engines, derived from DKW technology.

Zbrojovka weren't the only Czech concern to seek a licensing agreement with DKW at this time. Jawa would enter into a licensed arrangement to manufacture the DKW F2 in 1934. DKW two-stroke motor technology would go on to power both their automobile and motorcycle range well into the 1990s.

Jawa car history: https://dkwautounionproject.blogspot.com/2021/02/jawa-700.html 
Zbrojovka Z-6 brochure: https://dkwautounionproject.blogspot.com/2019/10/1935-zbrojovka-z-6.html

1949 Aero Minor II

Aero is not in any way related to Auto-Union, but there is a connection. The Aero Minor was actually designed and developed by the Jawa company, which got its start in the automobile business when they secured an exclusive license to manufacture the DKW F2 in Czechoslovakia in 1933. Shortly after production started in earnest in 1934 the relationship between Jawa and the newly founded Auto-Union soured and the two companies went their own ways. Jawa went on to develop their own range of cars, powered by a two-cylinder two-stroke engine derived from the 700cc DKW template. https://dkwautounionproject.blogspot.com/2021/02/jawa-700.html

In 1939, at the same time Auto-Union was working on the DKW F9 project, Jawa was working on a completely new vehicle with an in-house designed twin-cylinder two-stroke of 615cc. The new car, called the Minor II, featured a modern ponton body, making it a much roomier and more practical vehicle than the F9. When one of the DKW F9 pre-production cars broke down on a test drive through Czechoslovakia (Bohemia) in 1940, the car was towed to Jawa dealership for repairs. Jawa engineers managed to take a sneaky peek at their competitor and reported back to Prague that the Minor II was a far superior vehicle.

Of course, the Minor II could not go into production until after the war. Like Germany, Czechoslovakia's industries were stripped for reparations by the Soviets. The new socialist government recognized that the Minor II was a good, modern car but Jawa was in no position to begin manufacturing, being focused on motorcycles. Aero, which had started life as an aircraft company in 1919, had been manufacturing their own two-stroke engined cars since 1924. In 1947 they were still building the handsome Aero Type 30, but as the Minor II had better export potential, the government instructed Aero to take over production of the Minor.

The Aero Minor II proved to be a success domestically and in the export market, being sold all over Europe. It came in a variety of styles, including as a commercial. The model was even developed into a racer. The car was in production until 1952.

In the postwar period, Jawa became a specialized two-stroke motorcycle company which exported its products widely. https://heinkelscooter.blogspot.com/2022/07/1950-jawa-350-motorcycle.html

1939 Jawa Minor

1938 Jawa Minor Cabriolet

1938 Jawa Minor

The first Jawa cars were a license-built version of the DKW F2 model. As Jawa's relationship with Auto-Union became problematic from 1934, Jawa developed the Aero Minor as an independent design (although clearly based on DKW's two-stroke technology: https://dkwautounionproject.blogspot.com/2021/02/jawa-700.html

The postwar Aero Minor II was redesigned with a new body and an improved engine: https://dkwautounionproject.blogspot.com/2022/07/1949-aero-minor-ii.html