Im new to the forum, and to the harley davidson world. It seems to me that you are the people to go to when it comes to carb adjustments. I bought my 96 fatboy about a month ago. It has 2400 orig miles and has been pretty well taken care of. When I got it, it backfires through the carb when I first give it gas, then straightens out until I chop the throttle or the rpms get low at cruisiing speed. The previous owner installed a se kit that replaced the backing plate for the air filter and added the kn filter. I am pretty sure he didnt jet it and this is where my problem is. I am sure the rest of the bike is stock as far as performance. It may have a set of pipes or slip ons on it because it says "for offroad use only" on the back of the mufflers but im not positive of this. I have already adjusted the mixture screw, but after 4 turns out from seated I stopped because I knew it wasnt going to work. I have already did complete engine,primary, and trnny changes and also ran carb cleaner through the system as it has been ran since 2006. Been 3 or 4 tanks of premium ran through and its getting no better. Any suggestions would be greatly appreciated. Thanks in advance.