2002

Before this season, 2-stroke engines were the dominant type in the 500cc class. From this year, however, the race was re-branded the "MotoGP," and the regulation was changed to accommodate machines with 4-stroke engines. Under the new regulation, 2-stroke engines were limited to under 500cc and 4-strokes to 990cc. In response to this gradual shift to 4-stroke machines, Yamaha entered four teams fielding a total of eight riders. Yamaha also brought in the new 4-stroke YZR-M1 to join the 2-stroke YZR500. YZR-M1 showed its speed by taking 11 podium finishes in the 16-round series, thanks to a great riding of Max Biaggi and Carlos Checa. Biaggi won two races this season and finished 2nd in the ranking, while Checa finished 5th on the season. Garry McCoy, John Hopkins, Norifumi Abe, Pere Riba, Olivier Jacque and Shinya Nakano rode on the YZR500. Out of them, Abe finished the season rankedd 6th, which was the highest rank for a 2-stroke machine.

The opening race at Suzuka was met by rain. It was Biaggi's first time racing on the YZR-M1 and he ended up slipping on the white line and crashing out of the race. He continued to struggle in the early part of the season, with mishaps like a bad start in round two that left him 9th at the finish. He was also unable to score any points in round three. In the 4th round in France, however, he battled nose-to-tail in the rain with Honda riders Valentino Rossi and Tohru's Ukawa. He finished the race in 3rd place, six tenths of a second behind the winner Rossi. That put Biaggi on the podium for the first time this season. His performance got even better in round five, where he took 2nd place after a battle with Rossi. Biaggi finished 4th in rounds six and seven, and took 2nd place for the second time in the season in round eight. In doing so he brought himself back into the championship hunt. His performance continued to improve as he took 2nd in the 9th round in Germany behind Rossi with only a 0.7 second deficit. In the 10th round in the Czech Republic, Yamaha introduced a new cowling. This update helped Biaggi take his first win of the season. He also won the 14th round in Malaysia, bringing him up to 2nd in the championship ranking.

Checa, on the other hand, made a good start by finishing 3rd in the opening race. He maintained good form in the 2nd round in South Africa and finished 5th. His good pace continued as he finished 3rd in the ensuing rounds in Catalunya and the Netherlands. Checa took his season's best result of 2nd place in the 11th round in Portugal. However, he crashed twice while leading the race in the 8th round in Britain and in the 12th round in Rio de Janeiro. Although his stronger performance showed him to be a viable championship contender, these accidents ultimately left him ranked 5th at the end of the season. Towards the end of the year, Shinya Nakano, Olivier Jacque, Norifumi Abe, and Wataru Yoshikawa also raced on the YZR-M1. Garry McCoy, despite having experienced victories in 500cc, had to withdraw from four races due to an injury early in the season and ultimately ended the year ranked 20th.

In the opening round in Japan at Suzuka, local rider Osamu Miyazaki won the race with the TZ250 production racer. It was the first time in 17 years for the TZ250 to win a GP race, ever since Carlos Lavado won the San Marino GP in 1985.

Sebastian Porto from Argentina was on good pace, winning the 12th round in Rio de Janeiro. Porto ultimately finished 5th in the ranking. Porto began his season well by finishing 5th in the opening race. He finished the following races in 7th and 8th places. In the seventh round in the Netherlands, he made a strong recovery to finish 4th despite having to start from the pit lane because of a tire change. In the ninth round in Germany, he took the first podium finish of his GP career, followed by a 2nd place finish in the 10th round in The Czech Republic, which brought him up to 5th in the championship ranking. In the 12th round, he came 3rd in a race where only 13 out of 24 riders were able to finish the race. In Rio de Janeiro, Porto led the race well ahead of his rivals from lap one, and finished ahead of Roberto Rolfo (Honda) by 14 seconds. Porto finished 3rd in round 15 in Australia, but machine trouble caused him to finish with no points in the final round in Valencia. Porto ended the season 5th in the ranking.