Kleines Kettenkrad HK 101 (SdKfz 2)
A half-track vehicle with a motorcycle front end which NSU produced for the Wehrmacht from 1940 to 1945. Designed by Praxl Ewald and Ernst Schmidt, the Kettenkrad basically consists of a self-supporting sheet steel tub with dual caterpillar drives. The centrally mounted, water cooled, four cylinder in-line OHV engine was manufactured by Opel and produced 36 bhp at 3400 rpm: top speed was 70 km/h (44mph).
The driver sits on a standard motorcycle saddle mounted above the forward gearbox and two rear facing passenger seats were installed behind the engine, although this proved to be somewhat of a disadvantage in combat situations as the passengers had no emergency access to the steering. The steering itself is unique in that the front motorcycle wheel was generally used for light turns but a sharper turn actually engaged the track brakes to turn like a traditional tank. In fact it was recommended to remove the front wheel altogether in especially heavy terrain.