Founded at the height of WWI to manufacture armaments, Zündapp found a new role post-war as a producer of motorcycles under the direction of new owner, Dr Fritz Neumeyer, building its first machine in 1921.

The firm began making its own engines in 1924, selling more than 10,000 machines that year, and at the Berlin Motor Show in 1933 introduced the first of the horizontally opposed, four-stroke twins that it is best remembered for.

Among the models premiered were the K400 (398cc) and K500 (496cc) sidevalve twins, both of which employed designer Richard Küchen's unconventional all-chain four-speed 'gearbox' and shaft final drive.

Introduced at the same time was another Küchen design: a horizontally opposed four made in 598cc (K600) and 798cc (K800) capacities.

Common to all the larger models and eminently suited to withstanding the stresses and strains imposed by travel on unmade roads, the robust frame and girder forks were made of pressed steel, an advanced feature at the time.

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