[3] Knudsen won the 1980 Individual Speedway Junior European Championship[4] and recorded a 8.10 average for Coventry during the 1980 British League season.

Knudsen also raced in Australia during the 1980s, winning the "Mr Melbourne" title at the Melbourne Showgrounds in January 1987, and a week later finished third behind fellow Dane Hans Nielsen and American Rick Miller in the West End Speedway International at the Wayville Showground in Adelaide.

[5] Unfortunately for Knudsen, two fellow Danish riders Erik Gundersen and Hans Nielsen emerged and becam ethe world's leading riders, which arguably denied Knudsen his chance of becoming a world individual champion.

At the 1985 Final held in Los Angeles, Knudsen was undefeated on the night, famously holding out US team captain Bobby Schwartz in the penultimate heat to ensure Denmark could not be beaten.

[7] He announced his retirement at the end of August 1990 after a crash in Australia but returned to racing the following year.