I've an '06 FXDL fitted with 8 deg injectors, V&H BSS c/w quiet baffles, TP Eng's Scramjet filter, and a PCIII with map 811-003 i.e. BSS + SE air filter, however, it pops like crazy on deceleration! Does anyone have any tips on what adjustments I can make to smooth things out, please?

 

Nice looking machine.

Not sure if this may apply but I had the same issue after modifyingametric cruiser I had with new aftermarket exhaust, air filter and PC III.

Turns out with my metric cruiser, is that there is a component that lets fresh air into the engine upon decel to burn up any unused gas to help limit emissions. I believe it was described as the air induction system or something to that effect. The pop or backfire was actually supposed to be happening, I only noticed it because I had swapped out the stock exhaust which had been muting it. The fix for my bike was very simply to block the system that brings in that air. And since it's only used to burn up that spent fuel, it does affect anything else, so disabling it doesn't cause other problems.

I'd suggest finding out if HD's have that same emissions system or set up.

 

Not us maps work on UK bikes, But you need to add fuel in the low throttle position range, If you have any settings 0 or less@ 0 throttleup to 4000 rpm change to 20, If it still POPs add fuel @ 5% throttlle pos.

 

Also be sure to check the pipes where they connect to the heads. Be sure its still tight. If it sucks cold air it will pop. Otherwise sounds too lean.

 

I can tell you this much popping can be caused by too lean and too rich. For me a too rich pop has a deeper sound, and the lean pop a harsher, snappier sound. Generally lean pops are most common.

 

If it was my bike I'd concentrate on the 0% column only.
Putting 0's in from 500-1500 RPM
At 1750-4500 RPM's put the number 15 in the boxes, again,,in the 0% column ONLY.
Run the bike...see if it's better.
If it still pops some...change the 15's to 20's....
Run the bike....
If the pops are gone,,,you can go down one number at a time now...to 19....
Run the bike...no pops? Go down to 18...etc..until the pops return, then go back up..one number.