I know a million questions have been asked about this but i couldn't find an answer on this, I just did the jumper mod on a 07 zx6r and i was under the impression that doing this disabled the butterfly valve in the exhaust system. Only thing is, it doesn't ! the servo for the butterfly continues to move. If this isn't what the mod does, what does it do ??

 

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This has been answered many times before but I'm extremely bored so I will show mercy. The valve was installed not to restrict power, its true purpose is actually to increase power in the mid range. But because the bike becomes incredibly loud at high RPMs the valve was given a secondary purpose to restrict the noise on US models. Doing the jumper mod puts your bike in Euro mode so the valve will operate exactly the same in the mid range but will not restrict the power on the high end, making it illegal to run on the streets in the US. You will notice a significant increase in power, but only when your well into the triple digit speeds where the noise prevention would normally kick in. That being said I strongly suggest you take it on faith and not check for operation of the valve at 130, could get messy

 

moved

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