1922 Gnom (Horex) Cycle Attachment Engine 62.5cc 4-stroke on torpedo cycle. It's very rare german ‘Hilfsmotor”, restored and in running order.
Gnom was designed in 1920. The engine was well built and had a very good reputation. Manufactured in Oberursel, Germany by Horex-Columbia between 1921 and 1923 (see also: Horex Regina motorcycle).