It was a low-RPM machine, and only fired every other stroke due to the Otto cycle, also designed by Otto. The Otto engine was a large stationary single-cylinder internal combustion four-stroke engine designed by the German Nicolaus Otto. This is a video montage of the Otto engines running at the Western Minnesota Steam Threshers Reunion ( WMSTR), in Rollag, Minnesota. JSTOR ( December 2009) ( Learn how and when to remove this template message).
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