I fitted a stage one kit and Super Tuner Pro to my 2015 Fatboy using Screaming Eagle mufflers and filter, at the same stage downloading the correct tuning file for the stage one kit, it actually ran very well. I changed the mufflers for S&S turbo's and while it still runs fine, it pops and spits on closed throttle, anyone know why, is this normal and how to eliminate it?

cheers, John

1....wrong or poor tune
2....manifold or join at muffler has become a little loose from heat expansion, (leaking/sucking air)

check nut tension at these two points first, if o.k then do another tune

these are the most common causes of decell popping

check your clamps. Did you use new ones or reuse the old? I reused mine however took them apart and drilled out the splines on the middle section as it would not tighten to torque.

See this link

http://www.harley-davidsonforums.com/forums/exhaust-systems/36497-oem-exhaust-clamps-info.html

the slip ons have that cut in them to allow them to spread over the head pipe and make sure your clamps are covering the rear part of the split.

Mine popped a little and i re adjusted the clamps so they are more towards the rear and the pop went away. there was a black carbon stain right at the very end

My setup is pretty much standard except for XIEDS & K&N standard filter in the original housing & S&S slip ons

I have them on my FXSTC. They work and sound great. After I changed from stock to S&S turbos, I needed a re-tune (SEPST). Had the bike Dyno'd and it runs real sweet. They only time I get any decel pop is rolling of the throttle too quickly.. Thats probably more to do with technique rather than equipment.



It would appear that the pipes breath differently to your previous setup with the SE pipes (basically the S&S have no baffle in them), so my guess would be its a retune once you have eliminated the clamps and leaks.

M

Your 2015 Fatboy Screamin' Eagle mufflers would have had catalytic converters in them which increases back pressure and reduces noise. I bet the S&S ones don't have them so you have less back pressure so it will pop on decel. You have to have the tune redone to get rid of it.