Vincent Black Knight Vincent Black Knight The Vincent Black Knight is a British motorcycle made between 1954 and 1955 by Vincent Motorcycles. A year before the factory closed in 1955, Vincent produced the enclosed range of "Black Knight" and "Black Prince". Known as the 'Series D', the Black Knight was an upgraded Vincent Rapide which was fully enclosed to keep the rain and dirt from the rider. As well as allowing Vincent to reduce production costs, the enclosure actually improved performance by directing more air to the rear cylinder. Phil Vincent described it as a 'two-wheeled Bentley' and the enclosed Vincents got a
Vincent Black Shadow engine's ports. Early Black Shadows have a third inner valve spring not shared with the Rapide, but this feature was dropped from later bikes. Due to the low-octane 'Pool' petrol that was all that was available in the early post-war years, bikes of the period could have only low compression ratios. Although the prototype Black Shadow was built with a compression ratio lower than the Rapide's nominal 6.8:1, production Shadows have a ratio of 7.3:1 due to having different pistons from the Rapide, although still supplied by Specialloid. The Black Shadows have different carburettors than the Rapides, with Series B