I did my 500 miles service this morning on the Cross Country...a few hundred miles late but oh well. I used my service manual and went from front to back making sure everything was how it should be. I found my brake side floorboard mount had one bolt that was loose and then I got to the exhaust bolts at the motor the back port left hand screw was maybe finger tight at best the others were snug but no where near the 18 ft lbs it calls for. If you don't already know an exhaust leak will cause backfiring, popping or whatever you decide to call it. Mine wasn't but it was also just a matter of time before it would have started so before you blame a tune or a multiple of other things check your exhaust port bolts. Everything else on the exhaust was fine including all the fasteners on the bike. Belt tension was spot on and were the cables. Now I know my bike a LOT better.