OR engines were very popular on model airplanes for a number of years. I've got a .45, a .60 and a .90 in my old stuff. The fuel had to have castor oil for lubrication on these old timers otherwise the cylinder would score. Think they quit making them in the early '50's.
Didn't know they had made the bigger engines.
Mike
Didn't know they had made the bigger engines.
Mike