George Trimble, of Arizona, made his first engine in 1958. It’s an air-cooled, four-cycle single that burns gasoline on spark ignition. The ventilated crankcase is filled with oil for splash lubrication, but the exposed rockers required manual lubrication before operating the engine. The engine is 7”-long, 3”-wide, and 5”-high. 

George attributed its poor performance to his attempt to make his own piston rings. it had poor compression and burned a lot of oil, which led him in pursuit of a mathematical formula for making the “perfect piston ring.” the results of his efforts were published as a construction article in Strictly IC magazine entitled “How to Make Piston Rings.” This engine served as a test platform throughout his developmental trials to produce piston rings that would seat within minutes of starting an engine.

Exhibit added: July 1, 2009 - Last modified: March 16, 2023

Presented by The Joe Martin Foundation for Exceptional Craftsmanship