KTM 450 SX-F, 450cc , 2021, Orange. The championship winning KTM 450 SX-F is a proven formula that is the industry benchmark. For 2021, this machine continues to deliver superior performance and easy handling. It features an extremely compact, single overhead camshaft cylinder head and together with the efficient electronic fuel injection, it pushes out an unrivalled 63hp in the most effective way possible. The KTM 450 SX-F is simply the fastest Motocross bike out on the track.