Doug Hele had a challenge – four months to get six bikes on the grid. And there was more... three of these would be Triumphs and the other three BSAS, to reflect the fiercely competitive rivalry between the two principal brands in the parent BSA Group, each of which had its own Competition Department. It had been Hele himself who designed the 741cc in-line three-cylinder ohv engine powering the BSA Rocket 3 and Triumph T150 Trident over the winter of 1963/64, in his own free time and completely unaided, working on a drawing board in his home. The decision of BSA Group management to fund a racing programme was the direct result of a change in the rules governing AMA Grand National championship racing in the US, the British firm’s largest market. Until 1969 there had been a differential formula, with ohv and ohc engines restricted to 500cc in capacity, while side-valve bikes (i.e. Harley-davidsons) were allowed to measure 750cc. That year the ohv/ohc limit was raised to 750cc for dirt-track races, although bizarrely the 500cc handicap was retained for road racing. But in 1970 the AMA removed this curious restriction, which had no other obvious function than to keep Harley competitive. Doing so also provided the British firm with a chance to counter Honda’s threat to its triples’ potential sales after it upped the Superbike ante with the 1969 debut of its CB750 four-cylinder hyperbike. With just four months to get ready for the 1970 season-opening Daytona 200, the factory concentrated on race developing the threecylinder engines, and delegated construction of purpose-built road racing frames to specialist fabricator Rob North, whose shop was just 10 miles from the Meriden factory. North had already built frames successfully for Triumph tester Percy Tait, including one powered by a three-cylinder motor that Tait was very pleased with. This formed the basis of the six factory F750 triples shipped to Daytona, three Triumphs all ridden by Americans; namely Gene Romero, Don Castro and Gary Nixon – a two-time AMA champion for Triumph who’d already won the Daytona 200 in 1967 on a factory-tuned 500cc twin, plus three BSAS for Dave Aldana, Jim Rice and the legendary Mike Hailwood, coaxed back to bikes via a large cheque after switching to cars, for what he declared would be his last-ever bike race. Hailwood would have been the only Brit aboard one of the triples, but Rob North managed to construct a seventh bike at the last moment for his mate Percy Tait, who’d
The author on his own BSA3 during TT F1 support race at the 1984 British GP, Silverstone.