1935 - 1955
Legend says that Phil Irving, the Vincent chief-engineer, accidentally placed a wrong side up tracing of the Vincent 500 motor on top of an equally sized drawing of the same motor in such a manner that it formed a V-Twin. Moving it so that it would fit, resulted in the 47.5 degrees V-twin, which produced 45HP. Produced between 1935-1955, the 998cc Series A Rapide Vincent was capable of 110 miles per hour.
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