Hello im new to this forum , Would like to ask ? Has anybody had back fire issues after getting tune up/dyno . I presently have my 2004 ultra back for 3rd time @local harley shop to resolve backfire issue . Had no loud(shotgun loud) backfiring prior to original tune up/dyno . The bike has 103 big bore kit etc. & screaming eagle race tuner . Is it very hard to tune with these add-ons ??