Backfire While Up-shifting
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Cruiser
Joined: Sep 2011
Posts: 196
Likes: 0
From: South Carolina
What TTS cal are you running? I, too would play with decel enleamnment.. AE adjustments won't do much to help.
What RPM does this do this? Wind it up over 4k RPMs and let it coast down. When do you get that crack? If this can be narrowed down a bit, you could play with the Closed Spark settings and suck that crack back into the head a bit. Need more info.
What RPM does this do this? Wind it up over 4k RPMs and let it coast down. When do you get that crack? If this can be narrowed down a bit, you could play with the Closed Spark settings and suck that crack back into the head a bit. Need more info.
Banned
Joined: Jul 2008
Posts: 1,036
Likes: 67
Sounds like you might have an exhaust leak at the headpipe. Slip a 13 mm socket on a 4" extension and see if maybe you can't tighten it up a bit. There are two nuts on each headpipe. They have a compression gasket in there so don't stand on it, just snug it up till it quits popping. You also might have a loose muffler clamp on one of your mufflers.
Start with the easy fix first, which is cold air being sucked into a hot pipe which already has spark and fuel present. This can happen at decel or accel. It is fairly easy to tighten things up so this is the logical place to start.
If you are absolutely, positively certain there are no exhaust or muffler leaks (torque wrench is handy here) present then it is time to move on to fuel and spark. Most people usually want to start by adding fuel or taking away fuel to eliminate the popping. In some cases you can mask the problem of a leaky exhaust which is sucking in cold air by adding a small amount of fuel which might mitigate the problem for today but when the weather changes you are likely to have the popping return. That is why it is usually recommended to rule out the exhaust and muffler leaks first.
Tourer
Joined: Jun 2005
Posts: 463
Likes: 0
From: Des Moines, IA
I have dealt with this issue for over 2 years now. Multiple maps on PC-V (no auto-tune). Adjustments. replaced gaskets to no avail. Everything is tight and no leaks. Right now its at the best its ever been with only occasional up-shift popping. Sometimes I can prevent it others I can not.
If its really hot out it makes it worse.
So I am going to give up the 2-1-2 and am awaiting the Dragos Dragula 2-1 with their map and am crossing my fingers it will help. I will also switch out the head gaskets back from screaming eagle to standard. I have tried both now so far but Frank recommends the standard stock gasket so we shall see if I can get it in there and that it helps.
If its really hot out it makes it worse.
So I am going to give up the 2-1-2 and am awaiting the Dragos Dragula 2-1 with their map and am crossing my fingers it will help. I will also switch out the head gaskets back from screaming eagle to standard. I have tried both now so far but Frank recommends the standard stock gasket so we shall see if I can get it in there and that it helps.
Road Master
Joined: May 2012
Posts: 1,137
Likes: 8
From: illinois
I actually had the same problem recently. I have rhinehart 4" true duals a hd big air and a pcv. I changed out the rhinehart exhaust gasket with a se gasket. it seems to have fixed the problem. I would get some graphit spray and spray the gasket before you put a new one in and make sure to ride your bike and get it hot then retighten everything up...... and by the way the nut size is 9/16.
but after I redid all of this I still have a slight backfire at times. this could be im running to lean. my o2 plugs where very black when I pulled them out,
but after I redid all of this I still have a slight backfire at times. this could be im running to lean. my o2 plugs where very black when I pulled them out,
Banned
Joined: Jul 2008
Posts: 1,036
Likes: 67
I have dealt with this issue for over 2 years now. Multiple maps on PC-V (no auto-tune). Adjustments. replaced gaskets to no avail. Everything is tight and no leaks. Right now its at the best its ever been with only occasional up-shift popping. Sometimes I can prevent it others I can not.
If its really hot out it makes it worse.
So I am going to give up the 2-1-2 and am awaiting the Dragos Dragula 2-1 with their map and am crossing my fingers it will help. I will also switch out the head gaskets back from screaming eagle to standard. I have tried both now so far but Frank recommends the standard stock gasket so we shall see if I can get it in there and that it helps.
If its really hot out it makes it worse.
So I am going to give up the 2-1-2 and am awaiting the Dragos Dragula 2-1 with their map and am crossing my fingers it will help. I will also switch out the head gaskets back from screaming eagle to standard. I have tried both now so far but Frank recommends the standard stock gasket so we shall see if I can get it in there and that it helps.
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Tourer
Joined: Jun 2005
Posts: 463
Likes: 0
From: Des Moines, IA
Yeah I tried the standard gaskets when I swapped out the header the first time. I just re-used them and it was worse. With the SE gaskets they slipped right in and seemed to fit better with the header.
Outstanding HDF Member
Joined: May 2008
Posts: 2,543
Likes: 19
From: Ashland Ohio
I'm actually trying to help. Generic answers like a cal from George doesn't help. If you really wish for a bit of help. Answer the questions that I posted.
How about you open a Box-net account. They are free. Upload the tune to the box-net account and then post a link to that tune, here. So some of us can look at the actual tune in the bike instead of everybody guessing and NOTHING being fixed. Some of us work with TTS tunes everyday, so ya know why I am asking.
How about you open a Box-net account. They are free. Upload the tune to the box-net account and then post a link to that tune, here. So some of us can look at the actual tune in the bike instead of everybody guessing and NOTHING being fixed. Some of us work with TTS tunes everyday, so ya know why I am asking.
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