After wins in Denver and Oklahoma, Manxman David Knight could win a bonus of 50,000 US dollars if he wins the final round of the 2007 American Endurocross Series.
The prize is only paid if a rider completes a triple crown of victories.
He has already enjoyed a superb season in the United States of America by clinching the Grand National Cross-Country title at his first attempt.
Final day to give views on future of sidecar racing
Class was suspended at TT and S100 this year over safety concerns
Cummins and Sayle take podiums at Tandragee
Manx riders well represented in Northern Ireland
Cycling: Matthew Bostock takes victory at British championships
Top-ten elsewhere for Nicola Quaye during racing in Wales
Football: Isle of Man beaten in 2026 Cherry Godfrey Cup final
Manx side lose out on penalties against Jersey at Victoria Park