Floyd Landis plans to compete in the Teva Mountain Games in Colorado despite the ongoing doping inquiry which began after his 2006 Tour de France win.
Landis says he is confident his name will be cleared
The American tested positive for high levels of testosterone but has always vehemently denied any wrongdoing.
French anti-doping experts have begun analysing his B sample, and he faces a US anti-doping hearing on 14 May.
Landis will participate in road and mountain bike stages of the Ultimate Mountain Challenge on 2-3 June.
The event is a fundraiser for cancer research, and will mark his return to the saddle after a hip replacement operation last September.
Landis said on his website: "I am excited to put my new hip to the test racing in the Rockies.
"This is a wonderful opportunity to raise money for the Prostate Cancer Foundation at the same time."
Landis also plans to compete in Colorado's Leadville Trail 100, a 100-mile (160km) mountain bike race in August.
After his amazing stage 17 win in last year's Tour, Landis' urine sample was found to contain elevated testosterone levels.
The 31-year-old faces a two-year ban and would be the first Tour rider to be
stripped of the title if the doping allegations are upheld.