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Do Mufflers = Performance?

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Old Jul 29, 2016 | 05:20 PM
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Default Do Mufflers = Performance?

Have a post going about sticking with stock exhaust system or not. So far, the responses have been very helpful.

However, there has been some mention of performance and mufflers. I didn't think mufflers provided any gains in performance without doing a full stage 1. I was under the impression that the only reason to change mufflers without doing a stage 1, was if you just wanted a louder sounding muffler. Am I wrong?
 
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Old Jul 29, 2016 | 05:50 PM
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I'm sure other will chime in on this, but I have Rush Big Louies for the sound I wanted and everything else is stock on the motor. My butt dyno can't tell a difference.

I think the performance gains are noticed when more air goes in and a new tune to get the air/fuel mixture right. The better mufflers will allow better flow on the other end.
 

Last edited by RKZen; Jul 29, 2016 at 07:45 PM. Reason: typo
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Old Jul 29, 2016 | 07:03 PM
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Engines are air pumps less restrictive mufflers let more air out, intake & exhaust lets the engine breath.

Just adding mufflers by them self, will make the Bike sound faster, and run a little quicker.

I did read that on this here Forum.
 
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Old Jul 29, 2016 | 07:24 PM
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I do mufflers for mostly the sound and looks.I may do an air cleaner if the price is right.
 
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Old Jul 29, 2016 | 07:59 PM
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I have always been of the belief that just changing mufflers has little to no effect on power. That is until now. I just changed my stock mufflers to a set of Street Cannons and where previously I could feel the engine running out of steam before the 5500 redline and would shift. Now since the change I am now slamming into the rev limiter. It definitely is breathing better at high rpm. This caught me off guard as I always thought the cat was the biggest restriction and any change after it would do nothing.
 
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Old Jul 29, 2016 | 09:14 PM
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I do Mufflers for sound and to help the engine breathe better.
 
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Old Jul 29, 2016 | 10:52 PM
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It depends, if he mufflers are the restriction in the system yes, if not no.
3 points of restriction intake, cat, exhaust,

Full flow exhaust will maximize output, larger breather will allow more air in until that becomes the smallest orfice, increase throttle body size, until the cat becomes the smallest orifice. The more air, the more fuel you can add, the larger the volume of air/fuel mixture, the bigger the boom. The key is getting everything to match to maximize the energy.
 
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Old Jul 29, 2016 | 10:52 PM
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The problem with putting mufflers that flow too freely on a touring bike is, that for power you gain at higher revs, you lose the very bottom-end torque the stock mufflers give you.

I'll reckon there are ways to compensate, but I don't want to be bothered. I don't play the numbers game with modifications any more. I just want to ride.

"At the bottom" is where it counts for me. Never run the motor over 3,000rpm, anyway!
 
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Old Jul 29, 2016 | 10:54 PM
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A few years ago I bought an 05 xl1200r with a K&N air filter and debaffled pipes (stock casing but now straight). It was loud, wife hated it, but it pulled all the way to 100 with a windshield. It had no low end torque, none, at all. I found some new takeoffs (insurance) for $20 and fixed the noise and torque problem. It also fixed the speeding problem since the new top speed was about 85. I am slowly moving to something in between the two extremes. There is definitely a performance difference between stock and other , but the change in the torque curve may not always be ideal in all cases.
 
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