A performance car for the masses.
This was the goal for BMW R47 at the end of 1920. And to learn from everything that went into the construction of the previous generation R37-a powerful but complicated and expensive mechanical engineers of the German company failed.
The key is to keep an eye on production costs. Starting with a 500cc overhead valve engine from the R37, engineers added a simple frame and suspension, and took the necessary electronics. The end result was a bike that cost 36 percent less than the previous one, but she was still sporting ambitions, thanks to the engine. The boxer engine overhead valve was similar to the version used for the side-valve R42 tourer, but it pumped out 50 percent more horsepower, making 18 hp and a maximum speed of 70 mph. It was what the performance-minded drivers wanted, and the company sold 1,720 R47s-10 times more than R37-many of them to drivers of the German club. This is because BMW has not only suggest the use of R47 as a racebike, the company has encouraged. In fact, the street-legal electric components, a generator, horn and lights were an option. And the company offered a rapid secondary fuel tank that could be used for several trips or assigned to sprint competitions. But the R47 has also seen the competition at the highest level. A campaign team highly modified factory BMW R47s, hopped-up with compressors, beefier transmission and light frames. The R47 also shares another distinction with other BMW of his era. She was among the first truly modern motorcycles, with such elements as forward-looking roller bearings in the rocker valves, replaceable bushes throughout and a modern control layout (with the exception of the shift by hand). The R47 was sold for two years, and served as the basis for the R57 that followed. The machine's performance third-generation integrated with a more powerful front brake and transmission more robust in the proven design of the R47. This piece of history of BMW is currently on display in the "BMW: Mastery of Speed" exhibit at the Motorcycle Hall of Fame Museum in Pickerington, Ohio.
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