Carruthers, as the son of a motorcycle shop owner, learned how to work on bikes from a young age, started riding at 10, and entered his first race at 12.[2] By the early 1960s he had won the Australian 125 cc, 250 cc, 350 cc and 500 cc National Championships.[2]
In early 1966, he moved to Europe with his family to compete in British and International short-circuit races,[3] including Grand Prix World Championship events riding a Drixton Aermacchi,[4] and for early 1969 season riding bikes for the Aermacchi factory.[2] Halfway through the 1969 season, he was offered a ride with the Benelli factory and won the Isle of Man 250 cc TT race. After the Isle of Man TT, Aermacchi released him from their contract to continue as a factory rider with Benelli and, he went on to win the 1969 FIM 250cc road racing world championship after a tight points battle with Santiago Herrero and Kent Andersson.[1][2]
After the 1970 Grand Prix season, he accepted an offer from Yamaha to race in America.[2] By the 1973 season, Carruthers had taken on a wide array of responsibilities for the Yamaha team besides racing motorcycles.[5] He had also become team manager, crew chief, as well as a rider coach for his younger Yamaha teammates, Kenny Roberts, Don Castro and Gary Fisher.[5]
For the 1973 Daytona 200, Carruthers was responsible for preparing road racing machines for the entire Yamaha team, including the 250cc bikes to be run in the lightweight race. The Yamaha factory also asked him to prepare a motorcycle for the 1972 250cc World Champion, Jarno Saarinen.[5] Despite having such a full workload, Carruthers was able to place second to Saarinen in the Daytona 200, marking his best result in the race, which at the time was considered one of the most prestigious motorcycle races in the world.[5][6]
Carruthers stopped racing after the 1973 season to concentrate fully on his role as team manager and racing mentor for Roberts, who would win the 1973 and 1974 Grand National Championship for Yamaha.[2] When it became apparent that Yamaha didn't have a bike able to compete with the dominant Harley Davidson dirt track team, they decided to send Carruthers and Roberts to Europe to compete in the road racing world championships.[2][7] With Carruthers tuning the bikes and offering guidance, Roberts went on to win three consecutive world championships in 1978, 1979, and 1980. Carruthers also managed Eddie Lawson to a 500cc World Championship in 1984.
Carruthers went on to work for several Grand Prix teams through to the 1995. In 1996, he took a job with the Sea-Doowatercraft factory racing team, helping them win several national and world titles.[2] He returned to motorcycling in 1998 running a Yamaha satellite motocross team.[2]
^Motor Cycle 13 December 1964, p.45 Still on form. "As a final warm-up for his forthcoming European race debut, Australian star Kelvin Carruthers won four races on his two-fifty Honda four at the Victorian Grand Prix". Accessed 24 May 2014
^Motor Cyclist Illustrated, May 1968 pp.10, 12 Accessed 24 May 2014
