1946 Harley Davidson knucklehead
__________________ Production of the Knucklehead continued into World War II. In 1942, Harley-Davidson began to fit improved crankcases, or long-rib cases, since dealers had reported breakage problems with the earlier short-rib cases. Typically a crack would form on the left-hand crankcase, unfortunately, the same side that carried the serial number. Harley-Davidson even built a few experimental 3-wheelers fitted with the Knucklehead engine. Civilian production began again in 1944 with a few models designated for crucial positions. If you were a…