DKW racing engine of the 1930s I remember reading about a DKW racing motorcycle engine with three cylinders but one combustion chamber In essence the two outside cylinders were mounted vertically and formed a Twingle or split single unit while the middle cylinder was mounted horizontally facing forward in the frame had a larger bore and a smaller stroke and was essentially a supercharger for the other cylinders Does anyone have any documentation for this engine I think the motorcycles it powered were successful racers at the time