Ashley began racing in 1966 when he took a course at the Jim Russell Racing School. He was fast but rather erratic, and soon earned the nickname "Crashley". He reached Formula 5000 in 1972 and was a front-runner in 1973. He made his debut in Formula One in 1974, and briefly drove for the Williams team the following year. His luck got worse over the mid-1970s in Formula One. He was to become a victim of two nasty accidents on circuits that were no longer used by Formula One soon after his two accidents. During 1975, at the German Grand Prix at the Nürburgring where during practice, he crashed severely at the tricky Pflanzgarten section and broke both his ankles, and during practice for the Canadian Grand Prix at Mosport Park in 1977, he went over a bump, flipped his Hesketh, vaulted the barrier and crashed into a television tower. He never raced in Formula One again.