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Discussion Starter · #1 ·
just a bit of info for anyone thinking of getting the akrapovic exhaust
i find myself keep replacing the rubber tube from the air box to the exhaust keep getting burn off so i got it weld up today

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that tube keep getting burn to bits
 

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wrap some heat shield round it...
 

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It takes air from the airbox, and mixes it with the exhaust fumes.
The result is cleaner emissions.

It isn't exactly important. Some exhausts don't even have it!

Some people are also convinced that by removing (or blocking) this tube, you gain a performance increase, but it is yet to be proven either way.
It is often referred to as the 'air bung mod'
 

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The pipe that goes in to the exhaust pipe, you can leave open.
Like omar said, all that it connects to is a one way pipe.

The only thing I would be worried about is dirt getting in.
You ideally may want to close it off.
This can be done with absolutely anything, I would suggest perhaps a bolt or something like that, and then find a way to attach it on.

The other end, just cut the pipe short, and bung it off that end. It isn't important, as like Omar said, it only connects to a one way valve that allows air to flow from the air box to the exhaust.
 

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Discussion Starter · #13 ·
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The pipe that goes in to the exhaust pipe, you can leave open.
Like omar said, all that it connects to is a one way pipe.

The only thing I would be worried about is dirt getting in.
You ideally may want to close it off.
This can be done with absolutely anything, I would suggest perhaps a bolt or something like that, and then find a way to attach it on.

The other end, just cut the pipe short, and bung it off that end. It isn't important, as like Omar said, it only connects to a one way valve that allows air to flow from the air box to the exhaust.
when i had the scropion exhaust it didn't burn the tube
so that have me thinking because the scrop had cats in the down pipe so the down pipe didnt get so hot maybe i am wrong
the akra have no cats just down pipe right to the exhaust that leave me to think it gets hotter again maybe i am wrong
 

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my gpr has not cats and does get quite hot but it hasnt burned the tube off. maybe its the way the piping is shaped that affects how hot it gets?
 

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Some people are also convinced that by removing (or blocking) this tube, you gain a performance increase, but it is yet to be proven either way.
It is often referred to as the 'air bung mod'
It's done on all the 600 supersport racebikes, gives increased power, and makes dynoing it easier as the air fuel isn't messed up due to fresh air being injected. On the R1, it's connected to the crankcase breather as it gives better engine braking and also generates a little more power, as it is effectively doing what the crankcase pump does on the fireblade.
 

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It's done on all the 600 supersport racebikes, gives increased power, and makes dynoing it easier as the air fuel isn't messed up due to fresh air being injected. On the R1, it's connected to the crankcase breather as it gives better engine braking and also generates a little more power, as it is effectively doing what the crankcase pump does on the fireblade.
I can understand removing it for tuning...
Interesting that it would really affect performance.
I suppose on a bigger bike I can understand why....

Surely you can JUST as easily correct this by increasing the air intake hole sizes?
 
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