John Ephraim Sibbit (Jack Sibbit) (3 April 1895 – 5 August 1950 (or November) was a British track cyclist who won a silver medal at the 1928 Summer Olympics.By 41 he had held 12 national titles including tandem sprints, with Dennis Horn.Jack Sibbit built, rode and sold his own 'Jack E Sibbit' bicycles from premises at 475 Stockport Road, Manchester.