Popping, backfire, decel, lean, rich, etc?!

Help, I'm getting confused over some terms here. As a result of putting on new pipes (unbaffled at this time...on order), with an already jetted carb and free flowing filter from a previous exhaust system, I'm getting the typical popping upon decelerating and downshifting as predicted, but when I upshift through the gears and pull in the clutch grip, you should here the big explosive BANG!!! One Bang, per clutch pull. Is this backfire or what? I guess I'm concerned though, more about the fix rather than what its called. But what the heck is this?

Popping

So this has just happened since you changed your pipes?
What kind of pipes are they?
The pipes will probably work correctly after the baffles are installed.
Check that the header-pipes are at the "right torque"(no leak).
Check for an intake leak. (WD 40)
Check timing, do you have an VOES.
What year/model bike is it?
Good luck.

KB,

I am thinking the same thing. No back pressure and fat in the middle. Crackle, crackle, bang!

I have a '02 Deuce that was jetted for sreamin eagle mufflers, which in retro-spect was a good system. The pipes that I'm having trouble with are Hooker Steped Tuned Slash Cut Headers. Like I said, I've lost midrange pull and upshifting causes a loud BOOM with each clutch pull and shift. I hope that the baffles (muffler cores) that Hooker sells will do the trick. I'm wondering if the carb needs to be jetted again along with that. The jetting was done for the Sreamin Eagles. Hooker claims that with step tuned pipes there is no loss of low/midrange pull, but I obviously disagree. Thanks for your input.

Maybe

You might have to retune your carb, but I'd wait until you get the pipes right. Let us know what happens.

There is no appreciable loss of midrange when tuned properly. This is why Hooker and others offer different baffles. The Hookers come without any baffles which makes them drag pipes. Traditional drag pipes have reversion problems so you begin tuning from there. This is why they have a tuning baffle and a muffler cartridge.
Anytime you alter the back pressure you change the air flow through the engine. Changing the airflow changes the jetting. When you took off the SE stuff and installed Hookers you took all the back pressure off of the engine which changed the airflow. Add air, add fuel.