I recently put a snorkel kit on my 07 brute force 750i and it hasnt ran right since.  It idles and runs at low speeds fine, but when i get over 35 mph it spits and sputters.  i've tried re-jetting it, but now it runs worse...any other ideas???  

I am going to guess it is not getting enough air (running rich). If you put a larger jet in you probably made it worse. You could switch to the stock jet and temporarily remove the airbox lid to see if it runs right then. Something to try  

yeah i agree with redtecate