In fact, the manufacturer had an entire line of head-themed engines, including the Knucklehead, Panhead, and Shovelhead, with some featuring in the rarest Harley-Davidson motorcycles ever built.

In the 1960s, Harley-Davidson introduced another entry into its "head" series of engines, the Shovelhead, given its name because of its shovel-shaped rocker covers. Though the Shovelhead had its ...

Harley-Davidson Jaw Bone put together by Hog Killers went under the hammer earlier this month but failed to sell despite $30k ...