BMW R 51/2

The BMW R 51/2 was the first boxer motorcycle that BMW built after the Second World War. It was made only in 1950 and 1951 in a small run of 5000, and its successor, the R 51/3, was built in far larger numbers from 1951. BMW presented it on 18 October 1949 at the Bayerischer Hof hotel in Munich. Its predecessor was the R 51 of 1938 to 1940, with essentially the same chassis, telescopic fork and straight-line rear suspension. The engine is the last of the pre-war two-cylinder design with two camshafts over the crankshaft driven by a timing chain, and it has a single oil fill in circulation rather than separate fills for each head. The welded tubular frame has ball heads for sidecar use.