So my 2006 Vtx 1300 had started to backfire recently. Real bad too it is constant and very loud back firing. It only happened when I let off throttle though. I changed the plugs, wires, cleaned the carb, and tweaked the f/a screw and that seemed to do the trick. Now it idles way to high and seemingly maybe a bit out of time. I’m not sure if that’s the right way to describe but I know how my bike sounds and that sounds off.
I should mention that I have a cobra exhaust, cobra intake, and jet kit on the bike.
I mean no insult so please do not take it that way - are you sure you adjusted the A/F screw and not the idle adjustment knob? If your bike is stock, the knob below the air box is the idle adjustment screw and NOT the A/F screw. If you have the aftermarket Glen's A/F screw, it hangs right next to the idle adjustment screw so make sure you are adjusting the proper knob.
It helps all of us when someone reports back with their findings. If I come on a forum and ask for help with something I feel I should report back and let people know what the deal was since people were kind enough to help out. Not everyone thinks like that.