High Quality Content by WIKIPEDIA articles! The Velocette MAC (WD) was a British military motorcycle made by Velocette and was Velocette's first military machine produced for the Second World War. A reliable single cylinder, the MDD could cope well with the challenging battlefield conditions but Velocette's limited production facilities meant that it was a difficult to keep up production and by September 1942 the MDD order was cancelled and the factory turned over to other War work.