It takes brave riders to race on those narrow 2-lane country roads, with no runoff room like for a modern racetrack. Here is a little history for the Isle of Man TT racing, from Wikipedia:
Giacomo Agostini is the all-time leader in victories in motorcycle Grand Prix history, with 122 Grand Prix wins and 15 World Championships titles.
At the end of the 1965 season, Mike the Bike Hailwood left to join Honda as he had tired of working for the difficult Count Agusta. With Agostini now the top MV Agusta rider, he responded by winning the 500cc title seven years in succession for the Italian factory. He would also win the 350cc title seven times in succession and won 10 Isle of Man TTs.
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 his boycott of the event and by 1977, the event was struck from the Grand Prix schedule.
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