2) ENGINE: Governed engines, 3650-RPM max. (No Load). Single-cylinder Over-
Head Valve Engines must be stock, complete, and not to exceed a factory rating of 17
horsepower.. After market consumable parts such as air filters and spark plugs may be
used as long as they are a direct stock replacement. Old style L-Head engines may still be
used.
2011 rules bumped it up to 17 hp