URGENT HELP!! back firing like crazy

I installed a two brothers racing exhaust recently. Went for a 20 minute ride first. Then the next day went for an all day ride. It was fine for the first 5-6 hours. Last 1.5 hours it started backfiring like crazy. It was back firing on throttle in, slowing down, and on constant throttle. Almost home it shut it self down. I checked the oil and it was bubbly at first and a couple minutes later it was very running. Im assuming it was extremely hot and viscous. Limped it home after that.

Please help. Quad ride tomorrow id like to attend. Does it need a tuner or is it somthing else??