In the 1930s, BMW were producing a number of popular and highly effective motorcycles. However it was quickly found necessary to design an all-new OHV 750cc engine for the R75 unit. In August 1942, Zündapp and BMW, on the urging of the Army, agreed upon standardization of parts for both machines, with a view of eventually creating a Zündapp-BMW hybrid (designated the BW43), in which a BMW 286/1 side-car would be grafted onto a Zündapp KS750 motorcycle.
