John Surtees, a Formula One great who won the 1964 championship with Ferrari and remains the only man to win world titles on two wheels and four, has died at the age of 83, his family said in a statement.
The Briton won his four 500cc and three 350cc motorcycling world titles with Italian marque MV Agusta between 1956 and 1960.
Surtees was admitted to hospital in London last month with a respiratory condition and passed away on Friday after a short period in intensive care, the family said.
The statement was released through the Henry Surtees Foundation, established after the driver's son was killed by a bouncing wheel that hit his head during a Formula Two race at Brands Hatch in 2009.
Tributes poured in for a man who excelled at a time when motorcycling and grand prix racing was at its most deadly, with Ferrari hailing a 'motorsport legend" with a black and white photograph of Surtees and team founder Enzo Ferrari.
"Today the F1 family lost one of its all-time greats," said the official F1 website.
Surtees, whose father Jack was a national motorcycle sidecar champion, raced in both Formula One and motorcycling in 1960, when he also won the Isle of Man TT.
Known in his later years for forthright opinions on motorsport and an equally direct gaze, the Briton later fell out with Ferrari.
"Mr Ferrari agreed with me at the end, just before he died actually, that we'd both made a bit of a mistake in that we'd lost probably championships together with the parting that we did in 1966," he told Reuters in a 2014 interview.
In 1960 Lotus boss Colin Chapman wanted Surtees as his No.1 driver but the place ultimately went to compatriot Jim Clark, for some the greatest driver of all time.
Clark would go on to win the championship in 1963 and 1965 while Surtees beat Graham Hill by a single point in 1964 thanks to a scoring system that counted only the best six results.
