Giacomo Agostini 1967 he battled Hailwood in one of the most dramatic seasons in Grand Prix history. Each rider had 5 victories before the championship was decided in Agostini's favor at the last race of the season. Agostini dropped a bombshell on the Grand Prix world when he announced he would never again race at the Isle of Man TT, after the death of his close friend, Gilberto Parlotti during the 1972 TT. He considered the 37 mile circuit unsafe for world championship competition. At the time, the TT was the most prestigious race on the motorcycling calendar. Other top riders joined
Doug Hele The race win was repeated in 1967. At the 1969 Belgian Grand Prix on the Spa-Francorchamps circuit in the Ardennes, Triumph's factory tester Percy Tait led the world champion Giacomo Agostini for three laps and finished second at an average speed of 116 mph on Hele's Daytona racer. Hele had also started work on development of the three-cylinder Triumph Trident. "Motor Cycle"'s Technical Editor Vic Willoughby concluded his 1967 interview with Hele's confirmation that "...a high-performance seven-fifty parallel twin is not exactly at the top of the desirability stakes", and the triples were developed into the most successful race bikes