2002 Moves to MotoGP with the Pramac Honda team on an NSR500. A difficult season as the new four-strokes dominate. Retires at the end of the year.
2001 Continues with MS Aprilia Racing but changes back to the 250cc class. Finishes second in the championship with 273 points.
2000 16th in the 500cc World Championship with 38 points.
1999 Made 500cc World Championship debut (MAL). Classified 10th in the overall standings.
1998 Third in the 250cc World Championship. Was favourite to win second title after five wins, until knocked off on last corner of last race by teammate and rival Loris Capirossi.
1997 Third in the 250cc World Championship.
1996 Seventh in the 250cc World Championship.
1995 Second in the 250cc World Championship.
1994 Seventh in the 250cc World Championship. Year ruined by injuries.
1993 Won 250cc World Championship title in his first full year. Claimed first 250cc win, podium and fastest lap (AUS) and first pole (JPN).
1992 Won All-Japan 250cc Championship.
1991 2nd in All-Japan 250cc Championship.
1990 Second in the All-Japan 250cc Championship.
1988 Won Japanese Junior 125cc Championship.