Kawasaki Teryx ,running down the road 20 miles an hour and it died. Turns over slow like there is back pressure and won't start

Maybe it isn't the filter. Have you cleaned your gas tank, you may have junk in it. What about your exhaust, have you cleaned that. It sounds like the caburetor. Are you putting fresh gas in the tank? Are you putting K & N oil on the filter. Try another filter if you think that is the problem. Try using Seafoam in the gas tank, can get at O Riellys. Could be spark plug. To be honest it sounds like all the things mentioned above need to be cleaned