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Discussion Starter #1
I tore the exhaust system off of my bike this weekend, and the right muffler was almost rotted completely off right behind the goats belly. The left muffler had to be beat off of the belly, and was really stuck on there. The rest of the system come apart with no problems.
I purchased a nice set of pipes off of a sportster and the mufflers have a nice satin finish on them.
They were off of a newer bike, and the pipes have an O2 bung on them, and the mufflers have what looks like a catalytic system inside of them. You can't see through them, and it don't look like a baffle to me. I will post pics as soon as I can so you can see what I am talking about.
I will toss the goats belly and have some custom pipes made so I can get the mufflers to set even near the back wheel. I am also going to have a crossover pipe added. Will I need to re-jet the carbs? I will still be using the stock intake system, but will be going with K-N's
Thanks guys and gals.
 

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Linkmeister Supreme
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Shouldn`t need to rejet if you are keeping the stock intake, even with V&N foam filters inside the *ears*.

The square intake port on the back of each *ear* (air filter box) is the limiting factor in airflow to and from the engine. (The rubber grommet shims that port down to about 30mm (1 1/8") square, or ~9 square centimeters for each port.) Just installing a freer flowing exhaust should not cause a leaner fuel mix.

The lower exhaust back pressure caused by removing the goats belly/power chamber will likely cost some low end torque and acceleration though, in exchange for more top end speed potential.
 

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Discussion Starter #3
Thanks Ol Hoss, I thought that removing the goats belly I would lose some bottom end. That's why I thought if I had a crossover added, it would equalize the exhaust, and maybe add a little back pressure, if any.
Now all I have to do is figure out my wiring nightmare.
 

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Discussion Starter #4
I figured out my wiring issue, and fired her up with my new mufflers w/o the goats belly, and she sounds good. I have the popping issue, but the mufflers are not clamped down to the pipes, they are just sitting on there.
I adjusted the carb mixture screws to 2.5 turns, and that seems to be the best adjustment. I turned each one in all the way, and it did lower the idle considerably, so I think the carbs are good w/o any vacuum leaks.
I am going to post some pics of the mufflers w/o the belly, and with.
As soon as I get a bigger SD card for my camera, I will get some sound bites from each test.
Would there be any benefit from drilling the goats belly out? I want to drill straight through both sides, but I don't want to lose any bottom end.
I cranked the throttle open a few times today to around 4,000 RPM's, and it seemed a little flat at 3,000. Will tray again tomorrow with the belly in to see if there is any difference.
 

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Linkmeister Supreme
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Would there be any benefit from drilling the goats belly out? I want to drill straight through both sides, but I don't want to lose any bottom end
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I think drilling out the belly will lower back pressure and cause less bottom end torque too. It will probably be louder, but depending on your taste, it may not sound better. There is no free lunch. Anything you do to get a freer flowing and/or louder exhaust will cost low end torque IMHO.
 

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Discussion Starter #6
I understand that OlHoss. I think I'm going to do an experiment on mine this spring.
I'm off to a muffler shop tomorrow to have some pipes made.
1st is mufflers w/o the goat bolted directly to the headers.
2nd is w/o goat with pipes to make them equal on both sides near the rear wheel.
3rd is w/goat & stock hookups.
4th is w/goat and pipes to make them even near the rear wheel.
I don't like the offset on them. Looks weird to me.
I thought about using the Harley pipes and have them shotgun style and crossing over under the frame, and wrapping the pipes. The Harley pipes have a crossover built into them.
I will post pics, and hopefully sound as well.
 

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Discussion Starter #8
Nice lookin bike S58wish! The mufflers I have are a little longer, and have a nice satin finish as do the heatshields. I am going to try to make the stock heatshields work with them, but I also have the stock heatshields that came with the pipes and mufflers from the Harley they were on. They are painted black, and I am leaning towards having the shields powder coated black to go with my paint scheme.
I'm not one for a lot of chrome on a bike, too flashy for me.
I have finally settled on a color, and it's going to be green, something different form the norm.
 
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