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Perhaps I could get some guidance from you mechanically inclined types? I installed a set of dyno power fishtail mufflers on a set of Deuce headpipes in place of a Thunderheader. Running a forcewinder filter element and haven't changed jets. The muffler for the rear cyclinder is starting to get a slight amber tint. Not sure what to do about it. Does that mean I'm running lean? I would think that going from a T-header to baffled slip-ons would actually richen up my mix, but what do I know? Hence this post.
 

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I'm gonna powder his nose
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The muffler changing color is caused by several factors:
1) the air fuel ratio may not be correct.
2) the chamber in the muffler where the discoloration is may not be protected by a packing material thus the high internal muffler heat is discoloring that specific area.
3) GOLD is a sign of too rich.
4) Blue or rainbow color is too lean.

At this point a chrome cleaner MAY clean up the discoloration if you cure the problem (prolly too rich AFR) now.

Just to back up my estimation, do you get some popping or backfireing at all on decell?
Popping and more backfire gets worse in warmer ambient temps, lessens in cooler ambient temps?
If so it IS too rich in the AFR.

Easy fix.
 

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FOG
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stratslingr77 said:
Thanks for the helpful info. Next question: How do I lean it out?
I'm not sure I'd guess at this. You might well be running rich and need to lean it out, but if you're already running lean to very lean and you lean it out further, you could find yourself in trouble. For not too many bux you should be able to find a decent tuner who can check it out, maybe even on a dyno with a sniffer, and get it right.

T113
 

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stratslingr77 said:
Perhaps I could get some guidance from you mechanically inclined types? I installed a set of dyno power fishtail mufflers on a set of Deuce headpipes in place of a Thunderheader. Running a forcewinder filter element and haven't changed jets. The muffler for the rear cyclinder is starting to get a slight amber tint. Not sure what to do about it. Does that mean I'm running lean? I would think that going from a T-header to baffled slip-ons would actually richen up my mix, but what do I know? Hence this post.
Running rich or lean will cause the pipes to change color. They usually start out turning yellow, and if it's really hot, they will turn blue. In otherwords, lean will blue them, slightly rich will yellow them, and very rich will blue them, too. Retarded timing will also do this.

Any time you change the induction or exhaust systems, you must get it dyno-tuned. It's the only way to get it right on. Your pipes are changing color because of an incorrect AFR (air/fuel ratio). Also, MOST pipes I've seen will eventually start to turn yellow. That's why they make heatshields for them. :)

By the way, I wouldn't waste time buying that paint that's supposed to keep them from turning color. It won't last long at all. Think about is... the exhaust coming out of the head is at a temp of about 1300 deg. F. There just aren't many paints that will survive that kind of heat for very long, especially if the surface isn't perfectly clean and prepped. Most "high temp" paints are only rated to about 1200-1300 MAX. Add the hot gases flying out at high speed, and that paint will disintegrate quickly. Proper mixture and timing are the only sure fire way to keep the pipes looking good.
 

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05 Deuce
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I run the SEII slipons on my 05 Softail, and my head pipes turn blue with pipes at the mufflers turning yellow. Is this normal with just Stage 1 flash and SE A/C? These slipons sound good when you get on it, but when I'm just cruising in 4th or 5th, they sound terrible, kinda of raspy or muddy. Now I know why so many eventually get rid of their slip ons, and change over to new complete exhausts. I understand the Dynojet PCIII will help alleviate discoloring, and possibly bring more exhaust note in my top end. Just dont know if I want to just get it and stay with slip ons, or just get new exhausts.
I guess for $200 for SEII slipons, you get what you pay for.
 

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`05 FXDI
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ToddM said:
will eventually start to turn yellow. That's why they make heatshields for them. :)

So what do you do when the heat shields start turning yellow and the pipes underneath are practically black? My shields are welded onto the pipes and not removeable. I run BUB Chambermaids and I took out the baffles and put in the gold torque cones which were supposed to give enough back pressure. I'm fuel injected and don't have a fuel optimizer. When the shields started turning yellow I put the baffles back in and it stopped it from getting worse but of course they're still yellow. Anything I can use to get the chrome color back?? I'll buy the DFO and a bigger air cleaner before taking out the baffles again. :duh?:
 

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FOG
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kRiZ said:
.....but of course they're still yellow. Anything I can use to get the chrome color back??
You might try a really good metal polish like Wenol or AutoWenol. It's done a great job on yellowed pipes for me.

T113
 

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kRiZ said:
So what do you do when the heat shields start turning yellow and the pipes underneath are practically black? My shields are welded onto the pipes and not removeable. I run BUB Chambermaids and I took out the baffles and put in the gold torque cones which were supposed to give enough back pressure. I'm fuel injected and don't have a fuel optimizer. When the shields started turning yellow I put the baffles back in and it stopped it from getting worse but of course they're still yellow. Anything I can use to get the chrome color back?? I'll buy the DFO and a bigger air cleaner before taking out the baffles again. :duh?:
Running open pipes will cause you nothing but trouble. Those torque cones are ok for the older ironhead motors running drag pipes, but will really hurt performance on the EVOs or TCs and make them impossible to tune correctly. Leave the baffles in and get the bike dyno-tuned. Those are the reasons your pipes are getting so hot. If the heatshields are turning color, then your bike mixture is WAY OFF!! Once the pipes have gone as far as yours, the only options are to get them re-chromed, or replaced. You might be able to find something that will clean the heatshields, though. Someone here might have an idea... just do a search of the forums.

ANY time you change the air cleaner or exhaust, you must make sure you get it tuned properly (with a dyno or at the minimum, an AFR gauge) before you run it too much or you will screw up the pipes again.
 

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`05 FXDI
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ToddM said:
Running open pipes will cause you nothing but trouble. Those torque cones are ok for the older ironhead motors running drag pipes, but will really hurt performance on the EVOs or TCs and make them impossible to tune correctly. Leave the baffles in and get the bike dyno-tuned. Those are the reasons your pipes are getting so hot. If the heatshields are turning color, then your bike mixture is WAY OFF!! Once the pipes have gone as far as yours, the only options are to get them re-chromed, or replaced. You might be able to find something that will clean the heatshields, though. Someone here might have an idea... just do a search of the forums.

ANY time you change the air cleaner or exhaust, you must make sure you get it tuned properly (with a dyno or at the minimum, an AFR gauge) before you run it too much or you will screw up the pipes again.
I've had the baffles in for quite some time. Originally when I installed the pipes I ran then then for a week or so with the higher back pressure torque chambers in. I believe I referred to these as cones above, but that might have been misleading. These "cones" or chambers go in the end of the pipes where you would normally mount the baffles. I should have remapped/tuned the bike when I put them on but hey, what can you tell a new guy anything right? Anyways, it only took about 100 miles to turn the shields yellow and I realized I should probably put the baffles in instead of the chambers. No big deal really, it's just money right? My AFR appears to be fine with baffles in though I have not dyno'd it. They did not get any more yellow and the carbon deposit looks decent.

I plan on getting a big sucker and a DFO. Once I get those on the bike I'll try the torque chambers again and take it to shop to have it properly tuned. The yellowing doesn't look to bad so I'll just live with it if I can't find a solution to clean them.
________________

Here's the descriptive text on my pipes: (BUB Chambermaids)

"Tunable design includes two sets of torque chambers and a pair of baffles. Torque chambers allow the rider to obtain the aggressive sound of straight pipes and still maintain the correct back pressure for proper engine performance."
 

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kRiZ said:
I've had the baffles in for quite some time. Originally when I installed the pipes I ran then then for a week or so with the higher back pressure torque chambers in. I believe I referred to these as cones above, but that might have been misleading. These "cones" or chambers go in the end of the pipes where you would normally mount the baffles. I should have remapped/tuned the bike when I put them on but hey, what can you tell a new guy anything right? Anyways, it only took about 100 miles to turn the shields yellow and I realized I should probably put the baffles in instead of the chambers. No big deal really, it's just money right? My AFR appears to be fine with baffles in though I have not dyno'd it. They did not get any more yellow and the carbon deposit looks decent.

I plan on getting a big sucker and a DFO. Once I get those on the bike I'll try the torque chambers again and take it to shop to have it properly tuned. The yellowing doesn't look to bad so I'll just live with it if I can't find a solution to clean them.
________________

Here's the descriptive text on my pipes: (BUB Chambermaids)

"Tunable design includes two sets of torque chambers and a pair of baffles. Torque chambers allow the rider to obtain the aggressive sound of straight pipes and still maintain the correct back pressure for proper engine performance."
Yes, a lot of manufacturers say basically the same thing about their pipes, just the wording is different. That's what their advertising departments get paid for... :) That doesn't mean that the pipes will actually perform well on your particular bike, but they might IF it's tuned properly.

Still, you can't tell if your AFR is correct across the band by looking at the pipes. The only way to tell is to either use an AFR meter, or go through the tedious process of reading the plugs after tuning each fuel circuit, which requires a few sets of new plugs, a long open road for several high speed runs, and a lot of patience.

By all means, make all the mods you plan on making before doing the dyno run, but if you want it to run to the point only needing to pull your plugs once a year or so, then a dyno tune is mandatory! While it's on the dyno, you might want to try a run or two with and without the torque chambers.... if may perform better without them. That's a good thing about a dyno, you can do run after run, making changes along the way, to see what makes the most torque. I still firmly believe that if you want the best performance, you WILL need some kind of baffles in the pipes. Without them, you WILL lose a lot of performance!

Whatever you end up doing, good luck and have fun! :D
 

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Discoloring of exhaust components, whether it is tan, yellow, or blue, is a sign a excessive heat. The leaner the mixture, the higher the temperature. A too rich mixture, while not a good thing for other reasons, will not cause the pipes to yellow. When you increase the amount of air that is delivered through the engine, the air/fuel mixture will begin to lean because you don't increase the amount of fuel by the same amount, therfore the ratio of air to fuel becomes greater. This results in an increase in exhaust temperatures, which causes elevated exhaust component temperatures leading to the discoloration. You can usually get by without jetting/remapping if you only change the pipes, but any additional changes such as a high flow air cleaner will require additional fuel via remapping/rejetting.
 

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trooper113 said:
You might try a really good metal polish like Wenol or AutoWenol. It's done a great job on yellowed pipes for me.

T113
Use Bluejob. Buy it at harley shop if you can't find it anywhere else.
 

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Kevjud said:
Discoloring of exhaust components, whether it is tan, yellow, or blue, is a sign a excessive heat. The leaner the mixture, the higher the temperature. A too rich mixture, while not a good thing for other reasons, will not cause the pipes to yellow. When you increase the amount of air that is delivered through the engine, the air/fuel mixture will begin to lean because you don't increase the amount of fuel by the same amount, therfore the ratio of air to fuel becomes greater. This results in an increase in exhaust temperatures, which causes elevated exhaust component temperatures leading to the discoloration. You can usually get by without jetting/remapping if you only change the pipes, but any additional changes such as a high flow air cleaner will require additional fuel via remapping/rejetting.

Uhhh... yes, too rich a mixture will cause too much heat in the pipes, and will discolor the pipes. Since not all of it is burning in the chamber, it's burning on the way out. An EXTREMELY rich mixture will blue them. I've seen this happen on dozens of engines, so I know that it's a FACT. :)
 
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