2005 Raced in the AMA 125cc West Region Supercross series, best result a sixth-place at San Diego, Calif... Contested the AMA 125cc Motocross Championship, best result fifthplace overall at San Bernardino, Calif... Raced with Monster Energy Kawasaki team.

2004 Carpenter earned podium finishes at the St. Louis and Indianapolis rounds of the AMA 125cc East Region Supercross series... Raced in the AMA 125cc Motocross Championship, taking third-place overall at Washougal, Wash... Raced with Team Chevy Trucks Kawasaki.

2003 Carpenter raced a limited AMA 250cc Supercross season, taking his season best finish of ninth-place at San Diego, Calif... He returned to race in the AMA 250cc U.S. Motocross Championship, earning his season-best, seventh-place finish in moto #1 at Washougal, Wash... Raced with White Bros. Honda team.