Rossi vs. Rainey vs. Roberts vs. Lawson.For the first time ever, Yamaha's World Champions of the past 30 years will face off at Mazda Raceway Laguna Seca, the sight of many of their greatest victories - including Rossi's epic 2008 win over Casey Stoner that was the turning point in the MotoGP World Championship.Kenny Roberts (1978, '79, '80), Eddie Lawson (1984, '86, '88, and '89 on a Honda), Wayne Rainey (1990, '91, '92) and Valentino Rossi (2004, '05, '08 and '02 and '03 on Hondas) will square off in Yamaha TZ-250 super-karts at Mazda Raceway Laguna Seca late on the afternoon of Thursday, July 2, the eve of the Red Bull U.S. Grand Prix.The idea to get the world champions together was born out of discussions among Dorna, Mazda Raceway Laguna Seca, and Yamaha's communications manager Bob Starr. Said Rainey, "They asked me a couple months ago and I said, ‘Yeah, I think that could be fun. If you guys can put it all together, if we can pull this off, I think it'd be a lot of fun.' I didn't really think it could happen, but they did it. I think it's going to be a lot of fun."I think it's going to be good to have Kenny (Roberts) and Eddie (Lawson) and Vale (Rossi) and this is the only way I could get on the racetrack with those guys, so I'm glad these guys have agreed to say, ‘Hey, we'll get in a kart so we can all be out there together, so I think it's pretty cool."Though Roberts raced Lawson and Lawson raced Rainey, both on two and four wheels, the quartet of world champions have never competed against each other."I don't think we've all ever been out on the track together, so that'll be fun," Rainey, the USGP winner in 1989, '90, and '91, said. "We're doing it for Yamaha, doing it for the fans, doing it for the race track. We plan on putting on a show."Rainey said it had "been a while" since he last drove his kart. "It's been last year, maybe beginning of this year. I have a new kart and I've driven it once. I just haven't done a lot of driving recently just because I was building my house and had some other things going on. I just haven't had the time to really focus on it."This thing came together pretty quick, so I obviously want to get back in my driving suit and get some track time so I kind of don't look like an idiot out there too much."Lawson, the USGP winner in 1988, is no stranger to go-karting. An active kart racer, Lawson won the Superstars of Superkarts race which supported last year's American Le Mans race at Laguna Seca. Lawson's fastest lap in the race was a 1:23.924, which compares favorably to the 1:21.488 fast lap of Casey Stoner from the 2008 MotoGP race. Rossi grew up driving karts and won a regional championship in 1990 before splitting his time between karts and minimoto the following year. From '92 onwards, he concentrated on motorcycles. It's Roberts who will be new to go-karting, Rainey said."I think Kenny (Roberts) thinks he's just going to go out there and slide it around. They don't quite slide like that, like I think he's thinking," Rainey said. "It's going to wake him up a little bit. He's going to have fun. It's going to be a little bit different than anything he's ever driven like that. Short wheelbase, lot of power, lot of downforce."They're fun, they're pretty quick. Eddie (Lawson) gets around there. At Laguna Seca, I think, at our last race there, I think he qualified at 1:23. That's really fast for a little 100 horsepower TZ-250. Of course my dad (Sandy Rainey) builds a pretty special TZ-250, that thing is pretty special that Eddie gets to drive. Those things go around the corners really fast." Rainey said he and Lawson own the four karts that the foursome will race.The exhibition is tentatively scheduled for 3:30 p.m., though there are still a number of details to be worked out, including the length of the race."I think when Kenny drives this thing, he's only going to be good for about two laps, so he might be wanting a three-lap race, but we'll see," Rainey said. "It's going to be long enough that we're all going to have fun and everybody will enjoy it."Though Roberts promoted a number of U.S.G.P's at Laguna Seca, he never raced in one. His success came in national championship races, with Formula One wins in 1974, '76, '78, '79, '80, '82, and '84,The race is officially the "SuperKart Exhibition," but with four world champions on the track, someone has to cross the line first."Yeah, I would think there's probably going to be a winner," Rainey said with a laugh. "We'll just see who that is. Normally at Laguna Seca you never know who's going to win."