My 2006 FLHRI is back firing. I got the bike used with 12292 miles. when the bike was new the the 1st owner had a 95" kit from HD put in. When I went out for the first ride on the freeway it started to back fire. I had a TTS tuner put in and Vance and Hines exhaust put on. Well it still back fires. My mechanic is going to adjust the tuner. Some people also told me to put on true dual exhaust and that should take care of it, also I was told when they did the 95" kit they may not have dont the cams and might be to small of cams. any thoughts on this?