Professional motorsports is such a competitive trade that it's a big deal anytime a racer can string together more than a few victories, let alone a world championship. Occasionally there are drivers like Mario Andretti, Nigel Mansell, or Sebastian Loeb who can transition from one series to another, and find success in both.
But nobody else in the world has ever replicated the accomplishments of John Surtees. He is the only person in the world to have won World Championships in both cars and motorcycles.
Surtees grew up surrounded by motorcycles. His father was a motorcycle dealer. His first professional outing was in the sidecar of his father's Vincent motorcycle. They won that first race, but were later disqualified when officials discovered John was underage. In 1950 when Surtees was 16 years old, he went to work at the Vincent motorcycle factory as an apprentice.
One year later, he made headlines by nearly beating Norton's top driver Geoff Duke at the Thruxton Circuit. Four years later, at age 21, the Norton team gave Surtees a factory sponsored ride. He validated their faith in him by defeating Duke, then the reigning world champion, at Silverstone and Brands Hatch.
Going into the 1956 season, Norton's future in racing was uncertain. MV Agusta had already made an offer to Surtees, which he then accepted. In that very first season with the team, he immediately went on to win the 500 cc world championship.
Surtees proceeded to win 32 out of the next 39 races he entered in 1958, 1959, and 1960, claiming the 500 cc World Championships in all three of those years.
In 1959, in the midst of his motorcycle dominance at the age of 25, Surtees had been given test drives in F3 cars. In his first race at Goodwood, he finish in a close second place to none other than Jim Clark. Colin Chapman was persuaded by this performance to hire Surtees for the last four races of the 1960 Formula One season. In those four races, he managed second place in the British Grand Prix and nearly won in Portugal. His success convinced Surtees to focus his energy on Formula One. He immediately had several offers from various teams to consider.
Although he had an offer from Chapman to partner with Clark at Lotus, he instead opted to drive with Cooper in 1961 and Lola in 1962. Neither of those produced very desirable results for Surtees.
Despite those less desirable seasons, Enzo Ferrari had been watching closely. Being a former MV Agusta star made Surtees a favorite son of Italy. Ferrari hired Surtees to be the team's number one driver for 1963. In a close-fought battle with Clark at the Nürnburgring that year, Surtees got his first Formula One victory. In 1964, he won yet again at the Nürburgring, beating Graham Hill in his BRM. He also picked up another victory at Monza. The season climax in Mexico came down to Hill, Clark, and Surtees, all of which had two victories each leading up to the race that would determine the season's champion. Clark's Lotus suffered a mechanical failure and Hill's BRM was involved in an accident. With his second place finish, Surtees secured the 1964 Formula One World Championship.
Surtees had a reputation by those close to him for being a bit hard-headed. That embodied itself when tensions rose with the Ferrari Team Manager. So when Ferrari seemed like they would ultimately be less competitive in the 1965 Formula One season, Surtees ran his own Lola in the Class 7 (predecessor to the Can-Am series) Sports Racing Series.
Late in the 1965 season at Mosport in Canada, his car had suspension failure, resulting in a heavy crash. Surtees was heavily injured, but forced himself back to health for the return to the next year's Formula One season.
The next season at the Belgian Grand Prix at Spa, in a heavy, pouring rain, he won – to this day, one of his most well-known victories. Despite his success at Spa, it ended up being his last race with Ferrari. He and the team manager's relationship had become so contentious, it had come to a head.
Meanwhile, like many other formula drivers, Surtees was also simultaneously running back and forth to the inaugural 1966 Can-Am Series. Surtees, in his Lola T70, won 3 races of the 6 race series, becoming Can-Am's first champion over drivers such as Gurney, Donohue, McLaren, Amon, and Phil Hill.
He continued to work with Honda in 1967, giving them their second victory in F1. He finished 4th in the 1967 driver's championship.
In his eight years of Grand Prix Motorcycle Racing from 1952 to 1960, Surtees had 49 starts, with 38 wins, and was on the podium in all but four of those races. He won 4 world championships.
In his 111 starts in Formula One, he had 6 victories and 24 podiums, with one championship.
Either one of those two outcomes is an incredible career in itself. That they both were accomplished by the same person is practically unfathomable.