A Brief History of the Marque
Manufactured by VIS Aktiengesellschaft of Munich, 1923-1926
These were remarkable machines. The VIS Duplex had a 10hp 498cc twin-cylinder boxer two-stroke engine, and the VIS Simplex was fitted with a 249cc two-stroke; both had a three-speed gearbox. There was also a lightweight fitted with a horizontal engine of 1.5ps.
The firm marketed the lightweights fitted with the horizontal engine as Frimo, along with the Frimo Hilfsmotor fitted with the same engine mounted above the rear wheel of a bicycle.
Tragatsch states that the Frimo engine is a two-stroke of 246cc capacity.
N.B. There was also an Italian VIS marque built by Gazzi of Milan.
Sources: GTU Oldtimerservice, Tragatsch p140, motor-hist-foto.de, mvca.at