Originally Posted by ChickinOnaChain

You can see my set up in my signature picture and I get decel pop all of the time. I've gotten used to it and was told it's my style of pipes.

Originally Posted by hvymetl74

I have a 2013 Switchback and just had a stage 1 kit installed (V&H 2 in 1 slip ons, Stage 1 EFI Screamin Eagle air cleaner kit and Sceamin Eagle super tuner) This is my first Harley and friends advised me to at least add the Stage 1. Got the work done at my local Harley dealer. I've noticed the bike has more power to it but is the decel popping normal? It gives off about 3 to 5 pops on deceleration. Should I be concerned? I think it sounds cool but I don't want to damage the engine in the long run. Please help a first time harley owner and first time forum member. Thanks.

Originally Posted by JRK5892

100% it should NOT pop, it is the sign of a incomplete tune, not NORMAL, should be re tuned, and tables adjusted and should NOT pop

Originally Posted by Sharkman73

Did you get it dyno tuned? If not that is your solution. You said you have the SE super tuner pro & they can flash a map into the bike with it when you do these mods to get it close, but the purpose of the tuner is not just a flash, but the ability to dial the bike in perfect on a DYNO.
Anything less than a full dyno tune done by a competent tuner with good tuning software (SEPST, TTS, etc) is going to be less than perfect, which is unacceptable to me. Want it right, get it on the dyno. Best $350 or so you will spend on your bike.

Originally Posted by vdop

Big radius are very easy to eliminate popping completely. No need for a dyno. Two minor adjustments, about 30 seconds.

Originally Posted by deano360

please tell, the suspense is killing me..

Originally Posted by DK Custom

Decel popping does Not damage your engine...it is simply unburnt fuel that is burning in the exhaust tract after exiting the engine.

Decel popping occurs when one of two things are present.

1. The bike is so lean the exhaust is superheated and is burning the unburnt fuel that is in the pipes (there is always some unburnt fuel in the pipes no matter how lean). This is very rare.

2. The AFR IN THE pipes is just right to burn the unburnt fuel. This is quite a common occurrence when free flowing pipes are installed (whether or not a free flow A/C is installed). It can also occur if there is an exhaust leak that is introducing extra air into the exhaust tract.

Even if you like decel pop like the OP, it is always a good idea to check for leaks.

Also, check for intake leaks at the air cleaner and at the intake manifold/heads.

Another way to change the AFR IN THE Pipes is to install Thunder Torque Inserts.


If you don't like decel pop, and don't want to change the AFR in the pipes by changing the baffles or adding Thunder Torque Inserts....

....It is absolutely possible for a tuner and someone who knows how to use it to tune the decel pop out...although, with V&H and a few other pipes it is definitely more of a challenge.

HOWEVER, the methods used to tune the decel pop out of very open pipes are almost always at the sacrifice of performance and/or MPG.

An open pipe with the best performance tune is almost always going to have decel pop. To get rid of it the tune is changed from best performance to best performance possible with no decel pop.

I have never heard of anyone ever tuning a bike for best performance (with total disregard for if there is or is not decel pop)...where they are ONLY tuning for performance.... ending up with a bike that has open pipes with no decel pop.

There are hundreds of threads and thousands of posts from competent tuners on this forum who have strategies for getting rid of decel pop, and many of them are successful in doing just that. But they are adjusting the tune specifically to get rid of the decel pop. Why? Why not just tune it for the best performance? Because if they stopped there, there will be decel pop.

Since so many don't like decel pop, they then go and do further tuning (changing the best performance tune) to get rid of the pop.

Originally Posted by vdop

This is not even remotely close to true. The areas of the tables, usually ve and timing, are only adjusted in areas that the bike will only ever see on decel. Such as 0% throttle above 1500 rpm or very low map load timing adjustments (closed throttle) above 1500 rpm. How would adjustments at 0% throttle affect 100% throttle or any other throttle position for that matter? You can tune the bike perfectly for maximum performance and not affect that one bit by tuning out decel pop. I tune the bike on the dyno, while getting out what decel pop I can, then get rid of the rest after riding it. You can only do so much on the dyno, it needs real world riding to hear all the popping. Popping does not mean the tune is bad, that's just an extra step after completing the tune.

Originally Posted by DK Custom

We actually said the same thing.

Bottom line, 99% of the time (when there are no intake or exhaust leaks) decel pop does not damage the bike. It is unburnt fuel in the exhaust tract that is burning.

By changing the AFR in the exhaust tract you can reduce/eliminate decel pop. This can be done with by adding or reducing fuel in the combustion chamber which will change the AFR in the exhaust tract, or it can be done with TTI's or baffles, which also changes the AFR in the exhaust tract.

Originally Posted by deano360

ok cool thanks guys, this comfirms different things i have wondered..... thanks a bunch