Vincent Black Shadow and C bikes having 1⅛" Amal 289 carburettors and Series D bikes having 1⅛" Amal Type 389/10 units. While other contemporary motorcycles tended to be polished and chromed, founder Philip Conrad Vincent (PCV) decreed that the Black Shadow engine itself be black. The engine's signature colour was achieved by applying a "pyluminising" coating of chromate anti-corrosion primer over which a layer of Pinchin & Johnson black enamel was added. The part was then baked in an oven for 2 hours at . Although some have claimed that the black finish increased the rate of heat rejection from the engine, its
Black Prince (rocket) Aerospace author C.N Hill wrote that this declaration had been made: "Mainly, I suspect, to minimise the political damage that ensued from the [Blue Streak] decision". The 1957 concept design for a combined Blue Streak-Black Knight launcher was put forward once again, and this time received a favourable appraisal; the project was assigned the rainbow code of "Black Prince". In official documentation, the platform was referred to as the "Blue Streak Satellite Launch Vehicle" (BSSLV). The development of Black Prince was driven by the conjunction of the RAE and two private firms, aerospace manufacturer Saunders Roe and engine firm Bristol