What is a Knucklehead?
The knucklehead is a retronym used by enthusiasts to refer to a Harley-Davidson motorcycle engine, so named because of the distinct shape of the rocker boxes. The engine is a two-cylinder, 45 degree, pushrod actuated overhead valve V-twin engine with two valves per cylinder.
What is a Panhead?
The panhead was an ohv Harley-Davidson motorcycle engine, so nicknamed because the rocker covers resembled cooking pans. … The engine replaced the Knucklehead engine in 1948 and was manufactured until 1965 when it was replaced by the Shovelhead.
What is a Shovelhead?
The Shovelhead engine is a motorcycle engine that was produced by Harley-Davidson from 1966 to 1984, built as a successor to the previous Panhead engine.
What is a Flathead?
A flathead engine, otherwise side valve engine, is an internal combustion engine with its poppet valves contained within the engine block, instead of in the cylinder head, as in an overhead valve engine.
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