Decel pop
#1
Decel pop
I have a 2013 wide glide . I had Harley Put Vance and Hines big radius pipes on it before delivery. My question is . There is a lot of decel pop. Took it to Harley. They said its normal for thous pipes.they said they remapped it before delivery. Is it normal? I believe a programmer would fix this. Any suggestions ?
#3
Join Date: Nov 2010
Location: Red Banks, Mississippi
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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, 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). It can also occur if there is an exhaust leak that is introducing extra air into the exhaust tract.
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). This can be done with 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.
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). It can also occur if there is an exhaust leak that is introducing extra air into the exhaust tract.
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). This can be done with 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.
#4
With a real tuner, like Powervision or TTS, you can tune the decel out yourself. You add fuel to the far left column of your A/F map. On the Powervision, this is the 20 kpa column. (Deep deceleration shows MAP values of 10-11 kpa) This area of the A/F map is typically only entered when you let off the throttle and will have no affect on the other areas of the A/F map. All you do is take note of what rpm you are decel popping and then add fuel to that area of the map until its gone. Simple!
For reference, the bike normally idles in the 30-35 kpa range. Letting off the throttle is what puts you under 30kpa and that is the area you add fuel in. No where else!
For reference, the bike normally idles in the 30-35 kpa range. Letting off the throttle is what puts you under 30kpa and that is the area you add fuel in. No where else!
Last edited by jmeiers; 04-23-2013 at 01:42 PM.
#5
I have a 2013 wide glide . I had Harley Put Vance and Hines big radius pipes on it before delivery. My question is . There is a lot of decel pop. Took it to Harley. They said its normal for thous pipes.they said they remapped it before delivery. Is it normal? I believe a programmer would fix this. Any suggestions ?
#6
#7
With a real tuner, like Powervision or TTS, you can tune the decel out yourself. You add fuel to the far left column of your A/F map. On the Powervision, this is the 20 kpa column. (Deep deceleration shows MAP values of 10-11 kpa) This area of the A/F map is typically only entered when you let off the throttle and will have no affect on the other areas of the A/F map. All you do is take note of what rpm you are decel popping and then add fuel to that area of the map until its gone. Simple!
For reference, the bike normally idles in the 30-35 kpa range. Letting off the throttle is what puts you under 30kpa and that is the area you add fuel in. No where else!
For reference, the bike normally idles in the 30-35 kpa range. Letting off the throttle is what puts you under 30kpa and that is the area you add fuel in. No where else!
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#8
I can't speak for the 2013, but my 2012 had a decel pop when it was brand new with the stock mufflers on it. I put the Vance and Hines BSS on it and it still did it no difference. Had it tuned with the SEPST and it still did it although not quite as bad. My latest mod was to put the bigbore 103 along with the 204 cams in it and have it re-tuned and now no more decel pop and it runs stroooooong, I love it.
#9
[QUOTE=jeffreydsilver;11207289]09 Road King - American Custom slip ons - exact same problem
I put on a V&H Fuelpak - problem solved!
Quick question - If they said they "remapped" it, why does it have a decel pop?[/QUOTE
Either they really didn't remap it or they did it wrong. It was done under warranty. This is why I want to solve the problem myself. Lost confidentce in dealer
I put on a V&H Fuelpak - problem solved!
Quick question - If they said they "remapped" it, why does it have a decel pop?[/QUOTE
Either they really didn't remap it or they did it wrong. It was done under warranty. This is why I want to solve the problem myself. Lost confidentce in dealer
#10
Join Date: Nov 2010
Location: Red Banks, Mississippi
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A few thoughts-
It is very rare for an open pipe to NOT have decel pop when it is tuned CORRECTLY.
Decel pop is NOT a problem for the bike.
Decel pop might be a problem for some riders ears.
The majority of the time when decel pop is tuned out, it is done by dumping MORE fuel into the combustion chamber than is needed, thus sacrificing an optimum performing tune AND wasting gas.
If decel pop is really irritating, then dropping a bit of power by running too rich and using more gas than needed is probably worth it-BUT, that does not mean that it was not tuned correctly.
It is very rare for an open pipe to NOT have decel pop when it is tuned CORRECTLY.
Decel pop is NOT a problem for the bike.
Decel pop might be a problem for some riders ears.
The majority of the time when decel pop is tuned out, it is done by dumping MORE fuel into the combustion chamber than is needed, thus sacrificing an optimum performing tune AND wasting gas.
If decel pop is really irritating, then dropping a bit of power by running too rich and using more gas than needed is probably worth it-BUT, that does not mean that it was not tuned correctly.