Fritz Neuser had a mostly national career as a track cyclist. He was German champion in the tandem sprint in 1952, 1954, and 1955, in the individual pursuit in 1954, and added a German road title in the 1951 team time trial. He was also second in the German tandem sprint championship in 1953, 1956, and 1957, adding silvers on the road in the 1954 and 1956 team time trial. Neuser did have a bronze medal in the 1954 German road championship, also placing third in the 1951 German individual pursuit championship.
After his retirement as a cyclist, Neuser switched to four wheels and took part in many car races, particularly hill climbs and circuits. He also became one of Germany’s most successful car dealers, specializing in renovating classic Italian sports cars.