He was the 1997 F.I.M. world champion in the 125cc class on a Yamaha. The following year he switched to the Husqvarna factory racing team and repeated as 125cc world champion. In 1999, Chiodi won his third consecutive 125cc world championship, also on a Husqvarna. Chiodi moved to America in 2000 to compete in the AMA national championships without success. Afterwards, he returned to Europe to compete in the world championships before switching to the four-stroke world championships. Chiodi was a member of the winning Italian teams in the 1999 and 2002 Motocross des Nations.