# Grand Prix-wegrace van San Marino 1991

De Grand Prix-wegrace van San Marino 1991 was de twaalfde race van het wereldkampioenschap wegrace-seizoen 1991. De race werd verreden op 18 augustus 1991 op het Circuit Mugello nabij Barberino di Mugello, Italië.

## Uitslag
### 500 cc

| Pos | Nr | Rijder | Constructeur | Ronden | Tijd | Grid | Punten |
| 1 | 1 | Wayne Rainey | Yamaha | 24 | 46:08.566 | 3 | 20 |
| 2 | 34 | Kevin Schwantz | Suzuki | 24 | +2.946 | 1 | 17 |
| 3 | 3 | Mick Doohan | Honda | 24 | +6.066 | 2 | 15 |
| 4 | 5 | Wayne Gardner | Honda | 24 | +23.218 | 5 | 13 |
| 5 | 4 | Niall Mackenzie | Yamaha | 24 | +33.205 | 8 | 11 |
| 6 | 19 | John Kocinski | Yamaha | 24 | +37.614 | 4 | 10 |
| 7 | 6 | Juan Garriga | Yamaha | 24 | +39.280 | 9 | 9 |
| 8 | 27 | Didier de Radiguès | Suzuki | 24 | +39.566 | 7 | 8 |
| 9 | 21 | Doug Chandler | Yamaha | 24 | +52.121 | 6 | 7 |
| 10 | 8 | Jean-Philippe Ruggia | Yamaha | 24 | +1:15.609 | 10 | 6 |
| 11 | 17 | Eddie Laycock | Yamaha | 23 | +1 ronde | 14 | 5 |
| 12 | 11 | Marco Papa | Cagiva | 23 | +1 ronde | 15 | 4 |
| 13 | 16 | Cees Doorakkers | Honda | 23 | +1 ronde | 18 | 3 |
| 14 | 32 | Michael Rudroff | Honda | 23 | +1 ronde | 16 | 2 |
| 15 | 36 | Hans Becker | Yamaha | 23 | +1 ronde | 19 | 1 |
| 16 | 36 | Josef Doppler | Yamaha | 23 | +1 ronde | 22 | |
| 17 | | Romolo Balbi | Honda | 23 | +1 ronde | 20 | |
| 18 | 23 | Andreas Leuthe | Suzuki | 22 | +2 ronden | 21 | |
| 19 | 24 | Helmut Schütz | Honda | 22 | +2 ronden | 23 | |
| DNF | 39 | Michele Valdo | Paton | 14 | Uitgevallen | 17 | |
| DNF | 7 | Eddie Lawson | Cagiva | 14 | Uitgevallen | 11 | |
| DNF | 20 | Adrien Morillas | Yamaha | 12 | Uitgevallen | 13 | |
| DNF | 10 | Sito Pons | Honda | 7 | Uitgevallen | 12 | |
| DNQ | 13 | Nicholas Schmassman | Honda | 0 | Niet gekwalificeerd | | |
| DNQ | 29 | Larry Vacondio | Suzuki | 0 | Niet gekwalificeerd | | |

### 250 cc

| Pos | Nr | Rijder | Constructeur | Ronden | Tijd | Grid | Punten |
| 1 | 3 | Luca Cadalora | Honda | 20 | 39:49.345 | 3 | 20 |
| 2 | 2 | Carlos Cardús | Honda | 20 | +11.573 | 2 | 17 |
| 3 | 13 | Loris Reggiani | Aprilia | 20 | +19.913 | 4 | 15 |
| 4 | 7 | Masahiro Shimizu | Honda | 20 | +20.048 | 5 | 13 |
| 5 | 5 | Wilco Zeelenberg | Honda | 20 | +20.052 | 7 | 11 |
| 6 | 20 | Doriano Romboni | Honda | 20 | +22.956 | 10 | 10 |
| 7 | 15 | Carlos Lavado | Yamaha | 20 | +32.621 | 6 | 9 |
| 8 | 9 | Pierfrancesco Chili | Aprilia | 20 | +33.030 | | 8 |
| 9 | 6 | Martin Wimmer | Suzuki | 20 | +34.627 | 8 | 7 |
| 10 | 8 | Jochen Schmid | Honda | 20 | +41.643 | 13 | 6 |
| 11 | 72 | Herri Torrontegui | Suzuki | 20 | +43.033 | 20 | 5 |
| 12 | 46 | Max Biaggi | Aprilia | 20 | +43.039 | | 4 |
| 13 | 18 | Andreas Preining | Aprilia | 20 | +55.913 | 12 | 3 |
| 14 | 39 | Jurgen van den Goorbergh | Aprilia | 20 | +55.979 | | 2 |
| 15 | 33 | Stefan Prein | Honda | 20 | +56.103 | | 1 |
| 16 | 53 | Eskil Suter | Aprilia | 20 | +1:02.978 | | |
| 17 | 16 | Alberto Puig | Yamaha | 20 | +1:03.558 | 15 | |
| 18 | 51 | Jean-Pierre Jeandat | Honda | 20 | +1:05.607 | | |
| 19 | 48 | Urs Jücker | Yamaha | 20 | +1:06.224 | | |
| 20 | 19 | Marcellino Lucchi | Aprilia | 20 | +1:09.233 | | |
| 21 | 40 | Frédéric Protat | Aprilia | 20 | +1:18.735 | | |
| 22 | 45 | Corrado Catalano | Honda | 20 | +1:18.821 | | |
| 23 | 32 | Bernard Haenggeli | Aprilia | 20 | +1:19.211 | | |
| 24 | 47 | Fausto Ricci | Yamaha | 20 | +1:21.330 | | |
| 25 | 50 | Ian Newton | Yamaha | 20 | +1:49.524 | | |
| 26 | 34 | Patrick van den Goorbergh | Yamaha | 20 | +1:49.573 | | |
| 27 | 49 | Renato Colleoni | Aprilia | 20 | +1:49.590 | | |
| DNF | 4 | Helmut Bradl | Honda | 18 | Ongeluk | 1 | |
| DNF | 52 | Stefano Caracchi | Yamaha | 17 | Uitgevallen | | |
| DNF | 27 | Renzo Colleoni | Aprilia | 16 | Uitgevallen | | |
| DNF | 11 | Álex Crivillé | JJ Cobas | 16 | Ongeluk | 9 | |
| DNF | 30 | Harald Eckl | Aprilia | 9 | Uitgevallen | 11 | |
| DNF | 22 | Stefano Pennese | Aprilia | 4 | Uitgevallen | | |
| DNF | 44 | Bernd Kassner | Aprilia | 3 | Uitgevallen | | |
| DNF | 17 | Paolo Casoli | Yamaha | 1 | Uitgevallen | | |
| DNS | 37 | Erkka Korpiaho | Aprilia | 0 | Niet gestart | | |
| DNQ | 41 | Jean Foray | Yamaha | 0 | Niet gekwalificeerd | | |
| DNQ | 35 | José Barresi | Yamaha | 0 | Niet gekwalificeerd | | |

### 125 cc

| Pos | Nr | Rijder | Constructeur | Ronden | Tijd | Grid | Punten |
| 1 | 22 | Peter Öttl | Rotax | 18 | 37:57.546 | 4 | 20 |
| 2 | 1 | Loris Capirossi | Honda | 18 | +2.495 | 3 | 17 |
| 3 | 7 | Fausto Gresini | Honda | 18 | +2.631 | 6 | 15 |
| 4 | 28 | Ralf Waldmann | Honda | 18 | +2.673 | 5 | 13 |
| 5 | 9 | Alessandro Gramigni | Aprilia | 18 | +2.744 | 2 | 11 |
| 6 | 12 | Gabriele Debbia | Aprilia | 18 | +2.982 | 8 | 10 |
| 7 | 5 | Jorge Martínez | Honda | 18 | +23.625 | 7 | 9 |
| 8 | 35 | Kazuto Sakata | Honda | 18 | +23.673 | 9 | 8 |
| 9 | 4 | Dirk Raudies | Honda | 18 | +34.708 | | 7 |
| 10 | 15 | Maurizio Vitali | Gazzaniga | 18 | +34.944 | | 6 |
| 11 | 16 | Koji Takada | Honda | 18 | +34.992 | 13 | 5 |
| 12 | 3 | Bruno Casanova | Honda | 18 | +35.012 | 10 | 4 |
| 13 | 6 | Ezio Gianola | Derbi | 18 | +36.447 | 20 | 3 |
| 14 | 10 | Heinz Lüthi | Honda | 18 | +36.474 | | 2 |
| 15 | 11 | Adolf Stadler | JJ Cobas | 18 | +36.486 | | 1 |
| 16 | 50 | Antonio Sánchez | JJ Cobas | 18 | +36.618 | 12 | |
| 17 | 14 | Julián Miralles | JJ Cobas | 18 | +49.740 | 23 | |
| 18 | 20 | Hisashi Unemoto | Honda | 18 | +1:07.777 | | |
| 19 | 73 | Kinya Wada | Honda | 18 | +1:07.928 | | |
| 20 | 2 | Hans Spaan | Honda | 18 | +1:07.978 | | |
| 21 | 45 | Stefan Kurfiss | Honda | 18 | +1:08.282 | | |
| 22 | 44 | Serafino Foti | Honda | 18 | +1:08.332 | | |
| 23 | 46 | Arie Molenaar | Honda | 18 | +1:08.386 | | |
| 24 | 40 | Johnny Wickström | Honda | 18 | +1:09.278 | | |
| 25 | 52 | Oliver Petrucciani | Aprilia | 18 | +1:10.241 | | |
| 26 | 29 | Peter Galvin | Honda | 18 | +1:10.702 | | |
| 27 | 34 | Emilio Cuppini | Gazzaniga | 18 | +1:13.960 | | |
| 28 | 71 | Jos van Dongen | Honda | 18 | +1:29.497 | | |
| 29 | 64 | Hans Koopman | Honda | 18 | +1:38.964 | | |
| 30 | 49 | René Dünki | Honda | 18 | +1:39.549 | | |
| DNF | 56 | Noboru Ueda | Honda | | Ongeluk | 1 | |
| DNF | 17 | Steve Patrickson | Honda | | Uitgevallen | | |
| DNF | | Oliver Koch | Honda | | Uitgevallen | | |
| DNF | 41 | Alain Bronec | Honda | | Uitgevallen | | |
| DNF | 36 | Nobuyuki Wakai | Honda | | Uitgevallen | 15 | |
| DNS | 53 | Carlos Giró jr. | JJ Cobas | 0 | Niet gestart | | |
| DNQ | 31 | Ian McConnachie | Honda | 0 | Niet gekwalificeerd | | |
| DNQ | 43 | Manuel Hernández | Honda | 0 | Niet gekwalificeerd | | |
| DNQ | 45 | Thierry Feuz | Honda | 0 | Niet gekwalificeerd | | |
| DNQ | 49 | Janez Pintar | Honda | 0 | Niet gekwalificeerd | | |
| DNQ | 26 | Javier Debon | JJ Cobas | 0 | Niet gekwalificeerd | | |
| DNQ | 50 | Hubert Abold | Honda | 0 | Niet gekwalificeerd | | |
| DNQ | 62 | Stefan Brägger | Honda | 0 | Niet gekwalificeerd | | |
| DNQ | 32 | Luis Álvaro | Derbi | 0 | Niet gekwalificeerd | | |

### Zijspanklasse

| Pos | Rijder | Bakkenist | Constructeur | Punten |
| 1 | Alain Michel | Simon Birchall | LCR-Krauser | 20 |
| 2 | Steve Webster | Gavin Simmons | LCR-Krauser | 17 |
| 3 | Markus Egloff | Urs Egloff | SMS-Krauser | 15 |
| 4 | Egbert Streuer | Peter Brown | LCR-Krauser | 13 |
| 5 | Tony Wyssen | Kilian Wyssen | LCR-Krauser | 11 |
| 6 | Ralph Bohnhorst | Bruno Hiller | LCR-Krauser | 10 |
| 7 | Markus Bösiger | Peter Markwalder | LCR-Krauser | 9 |
| 8 | Theo van Kempen | Geral de Haas | LCR-Krauser | 8 |
| 9 | René Progin | Gary Irlam | LCR-Krauser | 7 |
| 10 | Darren Dixon | Sean Dixon | LCR-Krauser | 6 |
| 11 | Derek Brindley | Alan Langton | LCR-Krauser | 5 |
| 12 | Yoshisada Kumagaya | Brian Houghton | LCR-Krauser | 4 |
| 13 | Paul Güdel | Charly Güdel | LCR-Krauser | 3 |
| 14 | Werner Kraus | Thomas Schröder | Busch-ADM | 2 |
| 15 | Hans Hügli | Adolf Hänni | LCR-Yamaha | 1 |
1981 · 1982 · 1983 · 1984 · 1985 · 1986 · 1987 · 1991 · 1993 · 2007 · 2008 · 2009 · 2010 · 2011 · 2012 · 2013 · 2014 · 2015 · 2016 · 2017 · 2018 · 2019 · 2020 · 2021 · 2022 · 2023 · 2024 · 2025