 It recommenced with the Manx Grand Prix in 1946 and the Isle of Man TT in 1947, with a greatly expanded format that included the new Clubman's TT races.The Isle of Man TT became part of the FIM Motor-cycle Grand Prix World Championship (now MotoGP) as the British round of the World Motor-Cycling Championship during the period 1949–1976.Following safety concerns with the Snaefell Mountain Course and problems over inadequate "start-money" for competitors, there was a boycott of the Isle of Man TT races from the early 1970s by many of the leading competitors, motorcycle manufacturers and national motorcycle sporting federations.