Will the muffler off a 1000cc bike work on a 500? A friend is going to give me a dual tip carbon fiber jardine that I want to mount under the back end if I can.

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Sure, it will work, just have to fabricate it up

I used to have two Hayabusa Yoshimura TRS mufflers on my GS. They were the exact sale as the Yoshi TRS for the GS

Ok cool, so I won't have any issues with back pressure

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back pressure is BS IMO

It's just a matter of jetting the carbs based on the intake/exhaust combination

Yes! I have no complaints about my two brothers that was for a gsxr 1000. Only trouble I had was finding  the right size mid pipe to weld up

Quote from: weedahoe on November 26, 2013, 07:42:31 PM
back pressure is BS IMO

Internal combustion engines are basically fuel air pumps, back pressure is a very real aspect to take into consideration when it comes to how the "pump" performs.

Well  I got it but it was a under seat muffler. But I was able to cut tthe pipe and it fit right on where the guy had cut it off. Have it sideways but it actually turned out pretty good.

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Pics!!!  .. 

... oh and backpressure may play a part .. but at GS500 levels of performance?? ... would it make 'that much' of a serious difference?

I need to rejet anyway. Lol just gives me an excuse to give my wife to spend the money on the jets.. she thinks that because I got it running I dont need anything else.

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Quote from: Janx101 on December 02, 2013, 06:35:14 PM
Pics!!!  .. 

... oh and backpressure may play a part .. but at GS500 levels of performance?? ... would it make 'that much' of a serious difference?

Yes

well go on then! ...  .. not doubting it... just i was wondering about it.... a highly tuned turbo motor or some kind of performance engine... backpressure can make a large difference... i would think..

gs500 does not have a lot of performance... most of the mods people do gain... a couple HP if they lucky? ..

so seriously... how much is lack of backpressure going to effect the twin? ...

again... i dont know and im not saying it doesnt... not at all!! .. but what kind of effect and how much effect .. for on road performance? .. couple percent? .... significant (over 20%??) loss ..

is it a overall power losing effect .. or a smoothness/delivery effect?

saying "yes" tells me ... ok there is a change ... this chap knows there is a change .. but not what the change may be.. nor how much ...

so....... 

Flow, resistance, back pressure...call it what you want, it's all the same. And the effect is the same regardless of the size of the pump. The principle works on a lawn mower or a Hemi. Change the exhaust flow, you have altered the pump. That was my point.

EDIT: On the GS's level, a good exhaust system and proper jetting, you will gain more peak HP, how much IDK 

That was my thinking on it. A higher foe rate in your muffler means you are pushing more air, so you would need more fuel, I.e. bigger jets, to compensate. The result would be bigger, better combustion rates, therfore more hp. And richer rates on the bottom end of the rpm range would mean smoother acceleration.

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Edit for mistake

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Quote from: Suzuki Stevo on November 29, 2013, 04:15:56 PM

Quote from: weedahoe on November 26, 2013, 07:42:31 PM
back pressure is BS IMO

Internal combustion engines are basically fuel air pumps, back pressure is a very real aspect to take into consideration when it comes to how the "pump" performs.

You don't have back pressure; you have a more or less restrictive exhaust that influences how much air flow can pass through.  When you open up the exhaust (less restrictive) without any other changes the carbs won't meter enough fuel causing the bike to run lean.  The overall performance of the engine is best when the carburetors are tuned based on the restrictiveness of the intake/exhaust setup.  By running more air through (with more fuel)  and tuned for proper combustion you get more power from a less restrictive setup.

Very simple thought on backpressure:

First, reference the fact that chemical reactions (such as air and fuel burning) happen faster at higher pressures, and also happen faster at higher temperatures. Both pressure and heat are developed by compressing the mixture. Higher compression = higher power and higher efficiency, all else being equal.

Also note that exhaust is ideally inert and does not contribute to the air/fuel ratio.

So without backpressure, theoretically no exhaust is left in the cylinder and the pressure developed in the cylinder is completely fuel/air mix.


From there if we throw a wrench in the works and add in backpressure: Some exhaust gets left in the cylinder, and the cylinder becomes 'full' with less air and fuel since some of the space is taken up by the exhaust. Obviously this limits your power on the upper end.

But when you look at the lower end -- say you want your cylinders half full of air/fuel. Perfect flow means you get 50% air/fuel charge, and nothing else. With backpressure let's say you get a 50% air/fuel charge, and you also have 20% of the capacity still full of exhaust. You have more stuff in the cylinder to compress, meaning more power and efficiency for the same amount of air/fuel.


Of course, this is all extremely simplified. But it's also the same principal that allows direct injection engines (and an aspect of diesels) to be more efficient.

Quote from: radodrill on December 02, 2013, 10:21:30 PMYou don't have back pressure; you have a more or less restrictive exhaust

It's been called back pressure as long as I can remember and yes we are saying the same thing... http://en.wikipedia.org/wiki/Back_pressure

Ah c'mon Stevo! ..  you went all reasonable and agreeable way too fast there! ..  that's no fun!  Lol

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Quote from: Janx101 on December 02, 2013, 10:55:34 PM
Ah c'mon Stevo! ..  you went all reasonable and agreeable way too fast there! ..  that's no fun!  Lol

At least I didn't do this... >>CLICK ME!<<