Cox won his 17th from all cycling races for youngsters in which he participated, including the sprint at the World Championships for juniors. In the adult, he won the sprint championship ofNew South Wales and was fourth on the Australian sprint championship in 1948 and 2nd in 1949. In the 1950/1951 season, he became the national champion of Australia on the mile and 3rd in the Australian sprint championship. He managed to compete in the 1952 Olympics in Helsinki .
Helsinki Cox had with Rusell Mockridge tandem drive , even though he had never ridden a tandem race. Nevertheless, the Australian duo defeated the team of Hungary , Denmark , Italyand finally in the final South Africa . Cox also took part in the sprint, where he also reached the final, but was defeated by amateur world champion Enzo Sacchi . Cox remained an amateur and then in 1953 and third in 1955 at the Sprint Grand Prix for amateurs in Paris.