Was just reading the WSA rule book that went into print last month. Gone are the big 800's. 600 is now it for the open mods. I see no reference to them allowing 1000cc 4 strokers though. Reason for the change is stated as the inability to secure insurance for the 800's. Stock class is still 440's. They now will have a class for the Ski Doo Freestyle as well so I imagine it is only a matter of time till other manufactures make a similar model to race with as well.