Built in 1924-1925 by Dr. Ing Otto Steinitz of Berlin, the Dringos consisted of a reinforced bicycle frame with a two-stroke engine. Production ceased after less than two years.
It thought that Otto Steinitz's business may have distributed lightweight motorcycle engines from "Cambra" "Motorette" and "GS" (Gustav Schulze), from which the Dringos two-stroke was possibly derived.
Otto Steinitz was the author of automotive technical books including the popular Der Motor-Mechaniker and Der Motorrad-Mechaniker.
He was also well-known for the propellor driven passenger trains (Dringos-Wagen) which he had been developing since shortly after the end of the Great War which achieved express train speeds. Others worked on similar projects, the most famous of which was the Schienen-Zeppelin (Rail Zeppelin) of 1930. It was far faster than conventional steam trains of the day, with an appearance not unlike the TGV of half a century later.
Sources: GTU Oldtimerservice; Motopedia.
