Popping sound on deceleration
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, and does not occur with the stock map and free flowing pipes being the only change.
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).
To get rid of decel popping a lot of people put MORE fuel than is needed into the engine/over-richening the AFR so that more unburnt fuel goes into exhaust, changing the AFR in the exhaust so that is no longer optimum for combustion in the pipes. This is just a waste of gas. And if using decel enleanment found on most tuners it is still really hard to get rid of the popping/burbling when the injectors kick back in at about 1750 rpm.
Another way to get rid of decel popping is to change the AFR in the pipes (mufflers/Slip-ons).
The first thing to do, as mentioned above, is to make sure there are no leaks in the exhaust system letting extra air in.
If the AFR in the exhaust is still conducive to popping then you can try different baffles, a lolipop or Thunder Torque Inserts.
The benefit to the TTI's is that it will let you keep your sound, increase the low and mid range power, and reduce/eliminate the decel pop by reducing/eliminating reversion, thus changing the AFR (in the pipes) to one that is not conducive to combustion.
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, and does not occur with the stock map and free flowing pipes being the only change.
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).
To get rid of decel popping a lot of people put MORE fuel than is needed into the engine/over-richening the AFR so that more unburnt fuel goes into exhaust, changing the AFR in the exhaust so that is no longer optimum for combustion in the pipes. This is just a waste of gas. And if using decel enleanment found on most tuners it is still really hard to get rid of the popping/burbling when the injectors kick back in at about 1750 rpm.
Another way to get rid of decel popping is to change the AFR in the pipes (mufflers/Slip-ons).
The first thing to do, as mentioned above, is to make sure there are no leaks in the exhaust system letting extra air in.
If the AFR in the exhaust is still conducive to popping then you can try different baffles, a lolipop or Thunder Torque Inserts.
The benefit to the TTI's is that it will let you keep your sound, increase the low and mid range power, and reduce/eliminate the decel pop by reducing/eliminating reversion, thus changing the AFR (in the pipes) to one that is not conducive to combustion.
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Road Captain
Joined: Nov 2012
Posts: 569
Likes: 0
From: USA
Popping has nothing to do with being lean. It's unburned fuel vapors igniting in the hot pipes. Stop the air from getting to it, add fuel, decrease fuel, get rid of leaks, add timing, add some restriction to the mufflers, and the popping will subside. It's basically unburned gasses combined with just the right amount of air to get the fuel to pop off. Once the fuel to air ratio is upset to the point that it won't ignite it will cure MOST popping. Some exhaust designs just pop and even the best tuners can't totally get rid of it.
Club Member
Joined: May 2007
Posts: 145,895
Likes: 821
From: 40 miles Northeast of Indy..
Decel Gurgling, Decel Popping are not unusual on most after-market pipes.
If U get the Ka-Boom's or gun sound explosions in the pipes then something is wrong. Usually or most of the times if it starts after a pipes change its Air leaks.
After I had the SERT installed and dyno'ed with new muffs at 1k mine had really bad decel popping and the Ka-booms.. They retuned it and got about 1/2 of it out, Then I called Rush and in two minutes the Tech told me to check for Air leaks... Surprise,, I had Air Leaks in both pipes..
Took the bike back to the dealer and they removed and re-installed the pipes and clamps the correct way and got them sealed up on the headers , then re-dynoed again. After that it took care of 98% of all of the problem and now only gurgles some times at lower rpms and has the Jake brake sound the rest on decel's.
.
If U get the Ka-Boom's or gun sound explosions in the pipes then something is wrong. Usually or most of the times if it starts after a pipes change its Air leaks.
After I had the SERT installed and dyno'ed with new muffs at 1k mine had really bad decel popping and the Ka-booms.. They retuned it and got about 1/2 of it out, Then I called Rush and in two minutes the Tech told me to check for Air leaks... Surprise,, I had Air Leaks in both pipes..
Took the bike back to the dealer and they removed and re-installed the pipes and clamps the correct way and got them sealed up on the headers , then re-dynoed again. After that it took care of 98% of all of the problem and now only gurgles some times at lower rpms and has the Jake brake sound the rest on decel's.
.
Cruiser
Joined: Aug 2012
Posts: 169
Likes: 39
From: Peoria, IL
Decel Gurgling, Decel Popping are not unusual on most after-market pipes.
If U get the Ka-Boom's or gun sound explosions in the pipes then something is wrong. Usually or most of the times if it starts after a pipes change its Air leaks.
After I had the SERT installed and dyno'ed with new muffs at 1k mine had really bad decel popping and the Ka-booms.. They retuned it and got about 1/2 of it out, Then I called Rush and in two minutes the Tech told me to check for Air leaks... Surprise,, I had Air Leaks in both pipes..
Took the bike back to the dealer and they removed and re-installed the pipes and clamps the correct way and got them sealed up on the headers , then re-dynoed again. After that it took care of 98% of all of the problem and now only gurgles some times at lower rpms and has the Jake brake sound the rest on decel's.
.
If U get the Ka-Boom's or gun sound explosions in the pipes then something is wrong. Usually or most of the times if it starts after a pipes change its Air leaks.
After I had the SERT installed and dyno'ed with new muffs at 1k mine had really bad decel popping and the Ka-booms.. They retuned it and got about 1/2 of it out, Then I called Rush and in two minutes the Tech told me to check for Air leaks... Surprise,, I had Air Leaks in both pipes..
Took the bike back to the dealer and they removed and re-installed the pipes and clamps the correct way and got them sealed up on the headers , then re-dynoed again. After that it took care of 98% of all of the problem and now only gurgles some times at lower rpms and has the Jake brake sound the rest on decel's.
.
Am I the only one here who actually doesn't mind the sound? I kinda even like it to be honest!
I had it on my Screaming Eagle Mufflers and Stage 1 kit, and it got even louder with the V&H Bigshot Staggered...
After reading most of the comments, seems it won't really hurt the bike either
I had it on my Screaming Eagle Mufflers and Stage 1 kit, and it got even louder with the V&H Bigshot Staggered...
After reading most of the comments, seems it won't really hurt the bike either
poping
the popping is not normal and can be eliminated when the bike is tuned properly. You would thing its normal by the likes of all the bikes you see on the road that do pop. a lot of people change there pipes and do not want to spend the extra money on a tuner or a dyno tune.The bike will run ok and if you do not mind the popping ride it.
Intermediate
Joined: Feb 2013
Posts: 29
Likes: 2
From: newfoundland
Any difference between cooler and warmer weather? If it's worse in cooler weather it is most definetlly running lean, Cold air is more dense, meaning you're getting more of it.
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Novice
Joined: Oct 2012
Posts: 23
Likes: 0
From: Franklinton
consider tuning
Nikon is right...Tuner or tuning is the answer. i had the exact same problem. I used the V&H 2 into 1 big radious and I had popping on decel. I went with the HD fuel pack instead of the V&H tune. My bike is EFI. I brought mine to the dyno. Once the tune was perfected...No poping! The bike did run excelent before but you know the mixture isnt right if you are experiencing poping. Good luck!
You can tune for performance or tune for getting rid of decel pop.
If you tune for performance, it is very possible that you will get decel popping. It just depends on the configuration of your pipes.
Of course you can tune for getting rid of the decel popping, but most of the time you will be using more fuel and getting the same or less performance.
As stated above, make sure you have no exhaust leaks.
If you tune for performance, it is very possible that you will get decel popping. It just depends on the configuration of your pipes.
Of course you can tune for getting rid of the decel popping, but most of the time you will be using more fuel and getting the same or less performance.
As stated above, make sure you have no exhaust leaks.