Hendee Indian Rotary 7 Engine - -This is one of two rotary type engines built by the Hendee Manufacturing Company of Springfield, Massachusetts, manufacturers of the Indian Motorcycle.

Although George Hendee led the business, his fellow former bicycle racer Oscar Hedstrom was the principal engineer, and responsible for the company's brief entry into aviation. Several features of the French Gnome "Omega" engine were incorporated into its design, particularly the inlet valves which are similar to the Monosaupape engine

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