Seeley Motorcycles, produced in the United Kingdom from 1966 to 1979, was a motorcycle manufacturer founded by former racer and designer Colin Seeley in Belvedere, Kent. The company became renowned for its lightweight racing chassis and hand-built performance motorcycles, initially using AJS 7R and Matchless G50 engines before adapting power units from manufacturers such as Yamaha, Suzuki, Honda, and Norton. Notable models included the Seeley G50, Condor 500, Yamsel, and Seeley Honda CB750 conversions. Characterized by advanced frame design, racing success, and exceptional handling, Seeley motorcycles became highly respected among privateer racers and remain iconic examples of British competition engineering.