Decatted my SG
Road Master
Joined: Mar 2013
Posts: 1,040
Likes: 0
From: Indiana
The information available on this and all web sites is worth what you pay for it (most of the time) With that said I seen a post last week that said de=catting a header pipe would not change back presser at all ? So if you do a search you can find any answer you like .
Cruiser
Joined: May 2014
Posts: 174
Likes: 3
From: Commerce, MI
De-catting my stock headpipe exposed/aggravated a couple of lean spots in the factory tune. I rode it like this for about a week while i waited for my stage 1 package to arrive. Once installed, the surging and misfires went away. She now runs very smoothly.
Your results may vary.
Your results may vary.
Thanks for the spirited debate.
My bike is bone stock with the stock mufflers and even the stock Harley air filter. I understand the theory on back pressure and the possible lean condition that could occur when removing designed exhaust obstructions. I plan to watch my spark plugs for any signs of bad news.
In the event that there is something going on, I will make it a priority to get new mufflers, air cleaner and tuner to finish it out. Right now, everything I have read points to the little to no internal changes when only removing the cat.
Don't get mad at Wurk Truk. He is just upset that his sheep told him it needed some space.
My bike is bone stock with the stock mufflers and even the stock Harley air filter. I understand the theory on back pressure and the possible lean condition that could occur when removing designed exhaust obstructions. I plan to watch my spark plugs for any signs of bad news.
In the event that there is something going on, I will make it a priority to get new mufflers, air cleaner and tuner to finish it out. Right now, everything I have read points to the little to no internal changes when only removing the cat.
Don't get mad at Wurk Truk. He is just upset that his sheep told him it needed some space.
Outstanding HDF Member
Joined: May 2008
Posts: 2,543
Likes: 19
From: Ashland Ohio
Yup, I am sure a dumb ***.... what does that make some of you guys who have NO CLUE on tuning an engine?
Let's deal with XIEDS first. For a pipe swap? Not good, different pipes make for different VEs inside of the ECM. Know what a VE is? A 'tune' consists of TIMING changes and XIEDS do NOT do that, nor do they really effect open loop portions of a tune, like WOT. Pure *** snake oil and Tell Steve Mullens I said that. A $3 resistor does NOT make a $20k bike run correctly.
Removing the cat material decreases power to the bike. The scavenge effect of the pipe is ruined. The cat material does not, by itself make any less power than a true catless pipe, usually. The catless pipe WILL decrease temps appreciably. There WILL be times the EGR in a gutted pipe WILL effect a tune. Pipes work on sound waves and pressure waves. These wave go BOTH ways. The engine inhales thru the pipe. Did you know that? Without the cat material in place, it can inhale to the incorrect O2 sensor.
All you guys know is internet BS and have NO understanding of what tuning is about. All you have is you own bikes using butt dynos. Gimme a break. NOTHING scientific about THOSE methods, now is there? No dyno runs to prove your points? Same BS in the other thread. Like O2 sensors remove fuel only and an ECM can correct itself for pipe changes. Simply BEYOND ridiculous. Sigh.
And... to *******? Advertising in an open forum without you being a vendor is simply against the rules here. Don't like that? PLEASE leave this site. Or... the rules don't apply to you? Wanna keep thinking that? I will go to the shed to get you booted off of here. Try me! All you do for $125 is to rip folks off who have no clue what makes an engine run correctly.
Let's deal with XIEDS first. For a pipe swap? Not good, different pipes make for different VEs inside of the ECM. Know what a VE is? A 'tune' consists of TIMING changes and XIEDS do NOT do that, nor do they really effect open loop portions of a tune, like WOT. Pure *** snake oil and Tell Steve Mullens I said that. A $3 resistor does NOT make a $20k bike run correctly.
Removing the cat material decreases power to the bike. The scavenge effect of the pipe is ruined. The cat material does not, by itself make any less power than a true catless pipe, usually. The catless pipe WILL decrease temps appreciably. There WILL be times the EGR in a gutted pipe WILL effect a tune. Pipes work on sound waves and pressure waves. These wave go BOTH ways. The engine inhales thru the pipe. Did you know that? Without the cat material in place, it can inhale to the incorrect O2 sensor.
All you guys know is internet BS and have NO understanding of what tuning is about. All you have is you own bikes using butt dynos. Gimme a break. NOTHING scientific about THOSE methods, now is there? No dyno runs to prove your points? Same BS in the other thread. Like O2 sensors remove fuel only and an ECM can correct itself for pipe changes. Simply BEYOND ridiculous. Sigh.
And... to *******? Advertising in an open forum without you being a vendor is simply against the rules here. Don't like that? PLEASE leave this site. Or... the rules don't apply to you? Wanna keep thinking that? I will go to the shed to get you booted off of here. Try me! All you do for $125 is to rip folks off who have no clue what makes an engine run correctly.
Last edited by wurk_truk; Jul 1, 2014 at 07:27 PM.
Tourer
Joined: Jul 2014
Posts: 416
Likes: 14
From: Texas
Yup, I am sure a dumb ***.... what does that make some of you guys who have NO CLUE on tuning an engine?
Let's deal with XIEDS first. For a pipe swap? Not good, different pipes make for different VEs inside of the ECM. Know what a VE is? A 'tune' consists of TIMING changes and XIEDS do NOT do that, nor do they really effect open loop portions of a tune, like WOT. Pure *** snake oil and Tell Steve Mullens I said that. A $3 resistor does NOT make a $20k bike run correctly.
Removing the cat material decreases power to the bike. The scavenge effect of the pipe is ruined. The cat material does not, by itself make any less power than a true catless pipe, usually. The catless pipe WILL decrease temps appreciably. There WILL be times the EGR in a gutted pipe WILL effect a tune. Pipes work on sound waves and pressure waves. These wave go BOTH ways. The engine inhales thru the pipe. Did you know that? Without the cat material in place, it can inhale to the incorrect O2 sensor.
All you guys know is internet BS and have NO understanding of what tuning is about. All you have is you own bikes using butt dynos. Gimme a break. NOTHING scientific about THOSE methods, now is there? No dyno runs to prove your points? Same BS in the other thread. Like O2 sensors remove fuel only and an ECM can correct itself for pipe changes. Simply BEYOND ridiculous. Sigh.
And... to *******? Advertising in an open forum without you being a vendor is simply against the rules here. Don't like that? PLEASE leave this site. Or... the rules don't apply to you? Wanna keep thinking that? I will go to the shed to get you booted off of here. Try me! All you do for $125 is to rip folks off who have no clue what makes an engine run correctly.
Let's deal with XIEDS first. For a pipe swap? Not good, different pipes make for different VEs inside of the ECM. Know what a VE is? A 'tune' consists of TIMING changes and XIEDS do NOT do that, nor do they really effect open loop portions of a tune, like WOT. Pure *** snake oil and Tell Steve Mullens I said that. A $3 resistor does NOT make a $20k bike run correctly.
Removing the cat material decreases power to the bike. The scavenge effect of the pipe is ruined. The cat material does not, by itself make any less power than a true catless pipe, usually. The catless pipe WILL decrease temps appreciably. There WILL be times the EGR in a gutted pipe WILL effect a tune. Pipes work on sound waves and pressure waves. These wave go BOTH ways. The engine inhales thru the pipe. Did you know that? Without the cat material in place, it can inhale to the incorrect O2 sensor.
All you guys know is internet BS and have NO understanding of what tuning is about. All you have is you own bikes using butt dynos. Gimme a break. NOTHING scientific about THOSE methods, now is there? No dyno runs to prove your points? Same BS in the other thread. Like O2 sensors remove fuel only and an ECM can correct itself for pipe changes. Simply BEYOND ridiculous. Sigh.
And... to *******? Advertising in an open forum without you being a vendor is simply against the rules here. Don't like that? PLEASE leave this site. Or... the rules don't apply to you? Wanna keep thinking that? I will go to the shed to get you booted off of here. Try me! All you do for $125 is to rip folks off who have no clue what makes an engine run correctly.
Grand HDF Member
Joined: May 2007
Posts: 3,553
Likes: 17
Advertising in an open forum without you being a vendor is simply against the rules here. Don't like that? PLEASE leave this site. Or... the rules don't apply to you? Wanna keep thinking that? I will go to the shed to get you booted off of here. Try me! All you do for $125 is to rip folks off who have no clue what makes an engine run correctly.
The dude is not advertizing a product or service. He's selling his own stock pipe for one amount and offering to decat it if the buyer wishes for additional money.
Road Master
Joined: Mar 2013
Posts: 1,040
Likes: 0
From: Indiana
Look wurk_truk sorry you feel butt hurt and please do whatever makes you feel important . As for your threat knock yourself out you are one bad man .
If all it takes to get banned from this site is to call attention to a loud mouth bully see you in the movies .
If all it takes to get banned from this site is to call attention to a loud mouth bully see you in the movies .
Grand HDF Member
Joined: Nov 2012
Posts: 3,751
Likes: 459
From: Here and now
You aren't considering the relationship between short term and long term fuel trim and how a modification such as this can in fact change open loop fuel trim.
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