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Discussion Starter #1
Hi all, I tried removing the stock exhaust and replacing with a short tip but note that the bike lost a lot of low end torque with terrible throttle response. I suppose it's due to the loss of back pressure. Will a booster plug or something similar fix this? I really like the clean short exhaust look to show the wheels. Thanks everyone for any suggestions. The noise doesn't really bother me as I'm still running stock headers.
 

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Exhaust tuning is a fine art/science. You can't just lop a few inches off and expect the engine to run the same as it did before. No, altering the fuel air mix will not fix it. By "stock headers" do you mean with flapper and cat? Those will certainly cut the noise way down.
Plenty of the aftermarket exhaust can makers offer dB killers that usually don't do a whole lot of quieting but do provide some extra back pressure so you don't lose your low/mid torque.
If you just cut off the pipe behind the footpeg area, you could probably get a local muffler shop to fab you up a slip in plug with a hole in the center an inch or so in diameter, and stuff it up in the end of your pipe. have them weld a nut to it so you can drill a hole in the bottom of your pipe for a set screw.
A bit ghetto but it'll do what you want it to.
If you've already nixxed the flapper and cat and you're running an open pipe....you're in for a lot of noise and tuning issues. Other's may disagree but you'll find out soon enough. Good luck!
 

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I am running a straight pipe out of the cat and stock headers on my Racer - have no loss of torque or power - have run for past few months and confirmed no difference by putting the standard silencer on for a couple of hundred miles last weekend. Have kept the flapper because this may reduce noise at low revs which is useful.

Had same experience on my 1150 GSA - ran with straight pipe out of the cat for over 50,000 miles before replacing the whole system with a Black Widow exhaust. Strangely virtually no difference in noise with the GS either - can't say the same for the Racer!
 

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Discussion Starter #4
I guess my main problem is not so much loss of torque but the poor throttle response. Feels incredibly lumpy. Ran perfect once I switched back to the standard pipes. I was hoping running richer via a booster plug might fix this but guess not.
 

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I guess my main problem is not so much loss of torque but the poor throttle response. Feels incredibly lumpy. Ran perfect once I switched back to the standard pipes. I was hoping running richer via a booster plug might fix this but guess not.
What year is your bike?

Mine is a MY14.
Get ride off the flapper and install a booster plug at the same time, worked fine.
Then I lately swap the stock exhaust for a short tip and don't have any issues.
 

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Discussion Starter #6
Mine's a 14 too. Did u have to booster already on before u took the exhaust off? Just thinking if that's the difference maker.
 

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Discussion Starter #9
BP installed and happy to say the bike runs much better under this straight pipe setup. I quite like this clean look but it is really loud (and I'm still on stock headers with flapper), trying to figure out how I can lower the volume a little now, police here dun like noisy bikes...
 

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BP installed and happy to say the bike runs much better under this straight pipe setup. I quite like this clean look but it is really loud (and I'm still on stock headers with flapper), trying to figure out how I can lower the volume a little now, police here dun like noisy bikes...
you should look into the Supertrapp exhaust setup
 
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