Need some help from you guys.I have a 07fxd with the s/e air filter,Ecm download and s/e slip ons.Tonight I installed a k&n filter to replace the hd one and all of a sudden the bike pops and misses on acceleration.Anybody know of any fixes????

 

IMO (and I am no expert)... you now need to upgrade to an ECM like PCIII, Fuelpak, etc.

 

I am no expert on this,But you said you had a SE A/C,Then you said you replaced the HD with a KN and it started poping and skipping or just not running good,If you had a SE already on it that is a high intake if it had the back plate replaced and the rubber seal around the air intake removed.If you removed the back plate and also the rubber seal around the cover you changed the air intake alot and you will most likely need to install a sert ,PClll ,thundermax or some kind of race tuner,Thats my 2cent.

 

Fred
I had the same issue when I first did my setup. Had the HD race download, slipons and HD AC. When I dropped the HD filter and went to a K&N mine popped like crazy. My guess is that there is just enough difference in the volume or the air flow to cause this. Anyway, I went back to the HD filter till I got my PCIII and installed a good map for my setup. After that, I put the K&N filter back in and no popping.
Check everything including your clamps on your slipons as well as the nuts where the head pipes bolt on. Any of these being loose can cause this problem as well. I had to tighten mine several time after installing the slipons. Havent had a problem since I went with different pipes.
Good luck, let us know what you find.