Motorcycle Repair: Exhaust systems, suzuki gsxr 750, 1999 suzuki gsxr 750

Question
I was wondering what exactly a full exhaust system and a slip on or bolt on exhaust syastem do. Ie. Yoshimura.  If i was to have a  pipe that someone stripped out, what damage would that do to my bike? How would that effect my performance, and horse power?  Would that effect my valves or engine in any way over time.  What does the packing inside of the slip on pipes do, besides muffel the bikes sound. Thanks for the help.  Peter Mclaughlin
P.s. I ride a 1999 suzuki gsxr 750


Answer
Hi Peter.
 Since this is really a question for an engineer, I can't give you all of the answers to those questions.

Here's what I do know.
The exhaust system is designed to do a few things.  It gives the escaping exhaust gasses a direction to go and cools them a bit.

The packing in the muffler, helps to filter out some of the excess junk that didn't burn off correctly as well as muffling the sound and helping to create "back pressure" which an engine needs to run right.

Now, if you were to take a system that had been stripped out and use it on your bike, the entire engine would have to be retuned to accept the difference in loss of back pressure (along with all of the other things that go with it), which would adversely affect performance and burn out your exhaust valves.  It would also make you deaf in a week while getting you tickets all along the way for noise pollution.

Every motorcycle is designed to work optimally as it is from the factory.  If you want better performance, then take it to a professional tuner.

Remember that sounding fast and going fast are NOT the same thing.

Hope that helps.
FALCON