FIM reg MX1 the "Premier" class. 175-125 2 stroke, 290-450 4 stroke that leaves alot space for a 300+cc-sized 4 stroke brought it up because for me a @350 would with current tech fit me to a tee, for the skill level terrain type etc. I hope we see this in the next year or 2 with a tech based on the Xlite 250 motor, scaled up a little. I think Kato-om has one for Cairoli to play with (test) for the 10 season. Size does not matter lap times do. let the opinions/speculations begin!!