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I havnt read this anywhere but is there a reason why you cant just leave the pipe off your bike? The sound seems meaner and more aggressive than if you were to put a pipe on. I dunno, maybe I'm slightly retarded but perhaps there is a mechanical problem with this? What would happen to your bike if you were to do this?
 

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Bad bad things...from what im told it changes the compression and can burn the motor up but i could be wrong

i know its bad though
 

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Hall Monitor
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Crappy throttle response from a number of issues.  The muffler (even a relatively open, racing-stlye muffler) provides back pressure that keeps the bike from running too lean.  Yeah, you could re-jet, but there would be other issues.  

As the exhaust valves open, gases escape and move down the exhaust pipes at the speed of sound.  When the leading surface of this shock wave exits the pipe, a low-pressure pulse is created that travels back up the exhaust pipe.  The muffler (because of stuff like cone-shaped exhaust pipes, differently-sized chambers in the muffler, etc) tends to smear this reversion pulse, making it a longer-lasting but lower-amplitude low pressure zone.  With an open-ended pipe, you get a powerful reversion wave that sucks the exhaust gases out of the open exhaust valves at one very specific frequency, and maybe at certain harmonic frequencies.  The end result is a huge flat spot(s) in the power band where the exhaust is overscavenged.

That reversion wave can also carry cold air along with it, which can do bad things when it hits your very hot exhaust valves.

Oh, and instead of a nice, low, rumbly exhaust note, you just end up with something that's obscenely loud.

Other than that, no problem!

HTH

Bill
 

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It would be very very L-O-U-D. You'd also loose backpressure which would hurt your low end torque. Buy a slip-on like most of us do but after you cut the stock can off take a ride around the block. You'll be like:              :eek:
 

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Well, it'd violate noise reguations in pretty much every country in the western world  ;D

Engines in street tune need a certain amount of back pressure to run effectively.
Removing the pipes and headers would reduce your engine compression and the bike would
run pretty badly.

If you're talking about cutting the can off near the end of the pipe,
then you're basically running straight through pipes (no muffler)
and you'd lose some compression, but the bike should still run okay... it'd just be anti-socially loud.
 

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I was gonna post, but the last 3 said it pretty succinctly.  :)
 

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Hell, reversion waves are the bane of our civilized world!
Seriously, awesome post Bill.
 
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