Just put Fatcat 2into1, Power Commander and K&N RK 3910 on my 07 Fatboy. On deceleration I get A popping sound. It's not really a back fire just popping. Called D&Dthey told me to make sure the exhaust boltwere tight to 125 In. Lbs. Is the poppingnormal?

 

It's only normal if it's not tuned properly or you're getting an exhaust leak. Try loading a different map on your Power Commander. I'm sure others in this forum have the same set up... 2 into ones with PC.

 

PC map doesn't show a map for K&N. Looks like I may have to Dyno Tune.

 

K&N filter and the SE filter flow the same, thats not really your problem. You might want to bump up your mid and upper range mixtures a little to see if it gets better. Did you replace your crush gaskets (or exhaust gaskets)when you replaced your pipes? That could be your problem if you didnt. No matter how tight you make the bolts, if you didnt replace those gaskets it will leak.

Chris

 

Is it a pop or kinda a gurgle sound like air being sucked in? If its an actual pop, your probally a little lean. The gurglin sound is normal.

 

I did replace the gaskets, I'll try adjusting the air to fuel mix. Thanks for the help.

 

Is the popping you're getting on decel? If so, then it sounds like your Power Commader is
running to lean at the 0% throttle position. Try adding a value of say 15
from 1500-4000 RPM in the 0% columns ONLY. Put the number 15 in
each of the cells from those RPM's for cylinder 1 and 2. Take her for a spin
and see if that helped. If no popping, then reduce the numbers one or two at a time until the popping returns, then go back up one or two values.
Hope this helps,
Ride safe,

 

turn the screw all the way in and back out 2.5 turns...lol

 

Thanks soft06, I'll give it try.