Anyone have any feedback on the best dot approved knobby for a xr650? the Pirelli mt18 looks pretty good and i would think it would be the best, but the dunlop d606 looks not to bad either. Second question would be the size. stock rear is a 110/100/18. and the front is 80/100/21. would a larger tire both front and rear yield any handeling benefits? appriciate anyone with experience with either of these questions i would really appriciate some feedback. thanks, mike.