Just bought an 09 525 xc. Bought it from a dealer that the original owner traded in. Quads super clean. I didnt get to test drive it cause were getting hammered with rain here but it started and idled fine. I went to go riding yesterday and it started and idles perfect like it did at the dealer. I went to give it some gas to stsrt riding and it started spitting, sputtering and then backfiring. I revved it up into the high rpm and it clears up but pops and backfires on decel. I took the carb apart and cleaned everything. It wasn't very dirty to begin with but I figured I'd check. Put it back together and it still does it. Any clues?? Its got a fmf slip on. Jetting was 178 main, 62 pilot and 85 leak. Dealer said he rode it the day the previous owner traded it in and it ran great. I dont really believe dealers but im out of ideas. A lot easier to work on my banshee lol. Any advice would be great. Thanks!