The K&N should help it, If you don't do alot of deap water riding you can also experiment with univents to lean it out some more. I ride aat about the same altitudes about 1000 to 2000 feet.

Have you looked at carliles badlands radial I think it about the same as the ITP and you can find take offs at Polaris dealers. I bought a full set from a Poalris dealer for about 200.00. The Polaris Sportsmans use the same size tires as we do. They come off the brand new quads that the dealers sometime cusomize with custome wheels and big mud tires.

 

Have you tried to get your jetting better and if you did what helped? I've done the muffler mod,NAPA,Twin Air,DG3 and 142/145 combo.