See also Vincent-HRD.
The Vincent Black Prince was 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. Phil Vincent described it as a 'two-wheeled Bentley' and the enclosed Vincents got a lot of attention at the 1955 Earls Court show. Problems with production of the glass fibre mouldings eventually led to financial difficulties and the last Black Prince left the Vincent production line on Friday, 16 December 1955.
Falling sales of the Series C Vincent motorcycles during 1952 and 1953 was partly attibuted to dated styling, so Phil Vincent sought to update the range and development began what were to become the Series D machines. The main change was innovative full enclosure and weather protection, with glass fibre panels that included leg shields and a handlebar fairing. This was not about streamlining for speed, as the Vincent was already powerful enough for riders of the day - it was instead about the idea that the rider could travel to work in a suit rather than full motorcycle kit. Care was taken to ensure that the engines were still easily accessible for general maintenance and the rear enclosure was hinged providing access to the rear wheel and drive chain.
Vincent also tried to make it easier for the rider to get the motorcycle on to its stand by adding a huge lever on the left of the machine that could be operated from the saddle. The frame was also modified with a single tubular strut bolted to the steering head and a single damper replaced the twin rear shocks.
The Black Prince was launched at the 1954 Earls Court motorcycle show, together with the 998cc Vincent Black Knight and the 500cc Vincent Victor (which never went into production as only the prototype was ever built). There was a lot of interest but much of it was critical, and the Black Prince was termed the motorcycle you either love or hate. The Motor Cycle road tested a Black Prince and concluded that it handled as well as the Vincent Black Shadow with improved fuel consumption.
Production of the Black Prince began in the spring of 1955. Lucas components replaced the less reliable Miller electrical system and ignition was upgraded to coil and distributor. [[The rear enclosure, which incorporated the oil tank, was hinged allowing access to the rear wheel and final drive chain.Amal Monobloc carburettors improved starting. The centre stand was operated by a lever accessible from the saddle and the lower front mudguard stay served as an emergency front stand to facilitate the removal of the front wheel. Delay in delivery of the fibre glass components from subcontractors held back the availability of the first production bikes until spring 1955. Approximately 200 of the enclosed models were built.
Increasingly affluent customers may have encouraged Vincent to go for a 'high end' luxury touring model, but at the same time high volume and very affordable small cars were flooding the market. Vincent's accountants suddenly realised that they were losing money on every Black Prince sold, so the last example of both the model and the marque left the production line on Friday, 16 December 1955.