The 2010 AMA Rulebook outlines the details of the Lucas Oil AMA Pro Motocross Championship. After an incredible season in which the 250-class title came down to the final moto of the season and a record number of first-time winners broke through in the premier 450 class, it was clear that the sport’s roots are stronger than ever. As a result, the 30-minute-plus-two-lap moto format returns, providing the opportunity for the world’s best riders to compete again on the most challenging, yet safest, motocross tracks in the countryAdditionally, the fast 40 for both the 250 and 450 classes will be quicker than ever, as 90 riders across each class will battle it out to lay down the fastest lap possible and qualify for the final motos."We want to provide a clear, consistent rulebook for the riders and the teams," explained MX Sports Vice President Davey Coombs. "While we took a lot of ideas and suggestions into consideration for the upcoming series, we feel that the Lucas Oil AMA Pro Motocross Championship is already on the right track, and the best way to move forward is to stick with what we know and what our fans have come to expect. Discussions regarding the progression of the sport will continue throughout the upcoming season, because we will never stop trying to come up with ways to make the series work better for the riders and the fans."Reigning MX 450-class champion Chad Reed and defending 250-class title holder and premier-class rookie Ryan Dungey will lead the way in a star-packed 450 division, while 250-class runner-up Christophe Pourcel of France leads lineup of very fast newcomers in the that division. The action kicks off on Saturday, May 22, with the 42nd Annual Rockstar Energy Hangtown Motocross Classic in Rancho Cordova, Calif.You can see the new 2010 AMA Motocross Rulebook here.