Zündapp KS 600

The Zündapp KS 600 was the heavy boxer twin that carried Zündapp through the late 1930s, a shaft-driven machine of the K-series, whose letter refers to the Kardanantrieb, an enclosed driveshaft with two universal joints. First released in 1938 according to the Wikipedia article on the marque, it had a horizontally opposed twin cylinder overhead valve engine of 597 cc rated at 28 hp. It was often coupled with a Steib sidecar, the BW38, which was built from 1938 to 1941 and supplied exclusively to the Wehrmacht. The KS 600 was discontinued and replaced by the purpose-built KS 750, but its engine was the only part to live beyond the destruction of the war, because Zündapp reused it with few modifications in the postwar KS 601.