Sorry guys, but according to Stewart everyone except the top 5 guys in the sport should all but quit racing. Straight from his mouth.  He would still beat everyone except POSSIBLY the top 5 guys on a factory YZ250.  Seriously, I can't believe all these posts I keep seeing.  He did very well on the KX250 against all the 450F's.  If my memory is correct he was sometimes 20+ seconds ahead of #3 rider.  Now, the top 5 guys, maybe, they have really stepped it up.  But If Shorty is getting 6thish, on a bike that is probably almost identical as the 250 2 stroke in power output. Then James would do just fine on the 250 2 stroke, factory that is.