Well, im not expert with frame and suspension geometry, but I do know a few things.
First, the front frame rails of the 250r, where the arms mount up, is relativly narrow. I mean that the arms mount close to the center line of the frame. In return, this offers less bump steer, and over all better handling.
Another thing you will notice is the lengthy apearence of the R. It uses a long chassis with the front suspension far forward. Its motor is mounted towards the swingarm pivot point with plenty of room up front. Also, its swingarm length and alngle effects the way ii handles and hooks up.
Theres a load of factors that determine how a quad will handle..