Well my 2 cents.....you can't really tell what size someone's motor is by looking at it. The only way is to do a "motor pump". The only thing you can regulate is the type of motor. Horizontal, virtual, 2 stroke, yadda yadda....so im thinking next year horizontal motors ONLY....and if you say you got a 125cc, well that the class your gonna be next year.....its gonna get competitive fast, its kinda is already. So with that said as long its a horizontal motor, sky's the limit.....and get ready to race....can't wait for next year......this is just my 2 cents......