This is starting to get really confusing. The latest proposal for the 2011 four-stroke replacement for the 250GP class was unveiled today in Catalunya: 600cc engine, prototype chassis.
Just to help everyone keep up, Carmelo Ezpeleta, head of Dorna (which
owns GP racing) originally proposed a 625-650cc prototype class. That struck everyone as pretty stupid since it got too close in capacity to
both MotoGP and World Supersport, all while ignoring GP racing
heritage. Aprilia and KTM (as well as every single racing fan) got
upset, then KTM proposed a 500cc, two-cylinder class. Fans cheered.
Then today, the Motorcycle Sport Manufacturers Association threw out
KTM's proposal and reduced Ezpeleta's proposed capacity to 600cc,
confounding everyone. The MSMA vote was not unanimous, though at this point we
don't know who voted which way.
The class change will again be considered June 28 at Assen, but at this point, we're afraid the move to a 600cc capacity is inevitable.