In 1938 NSU began the development of the 350 & 500cc RK bikes. Chief designer was ex-Norton engineer Walter Moore with Albert Roder (ex-Zundapp) as his assistant. The motor was a DOHC parallel twin with bevel drives to each camshaft. A supercharger was fitted behind the cylinders. Two 350s and a 500 were raced at the 1939 IOM but none finished. After the war supercharging was still allowed in German domestic racing up until the end of 1950. NSU returned to competition with revised versions of the RKs in '49 with Heinz Fleischmann as their main rider and BMW as their principal competitor. The 500cc bike made 98hp at the start of the '49 season with a top speed of 270kph. 110hp was available for record breaking attempts in 1951 & 1956 when a RK powered streamliner achieved 330kph. In 1966 Wilhelm Herz raised the 10k speed record to 309kph. This is one of the five RK500s built.
Fine photography by Phil Aynsley