Can someone give me desciption and rules for the different classes, i see so many different racing classes but not sure what they allow racers to do to the bikes and still race. MotoGP Superbike (SBK) the classes that Rossi is in, also Mladin Spies Hayden What type of mods are allowed in these classes and what other classes are out there? Whats the toughest class with the best guys? Any info is greatly appreciated! thxs yo!