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I just want to get the record straight on this from people in the know, i've heard so much about this subject but no clear answer.... If I remove the exaust butterfly valve I do not need the jumper mod? If I install a PCIII, i do not need the jumper mod? Basically what i'm asking is what does the jumper mod do? Is it just the exhaust valve or also ignition/fuel management modification? Will a slip-on make the jumper mod uneccessary? Will a PCIII do what the jumper mod does? Help on this from somebody that knows
 

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Debate

I recommend the jumper mod to anyone who understands it. What happens is that during high rpm's the secondary fuel injectors limit the amount of fuel entering the cylinder. We're talking about the last few thousand RPM's before red-line range. In the US for whatever purpose (Smog or noise constraints) we have this limit in Europe and the rest, this is not in case. The jumper simply removes the fuel restriction , so rev away! The difference will only effect you if your really going fast, or at the track. PC3USB is a good fuel management box although it only connects to the primary injectors, not the secondary. So yes, a benefit to be had from each of these individually, but were talking super fast vs. really fast.
 

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even red lining or hitting stupid rpms. is doing your bike good. having remarkable fuel management in the upper rpm range. is it good too red line i think not if u know your bike u can kick the shit out of some one that red lines. i run my bike too 12000- no more then 13000 sometimes not very often just too releas pressure on the valves and cams and pistons. and i normally ride with hard shifts of 10000 and still kicks ass for thoes who run there up to red line...,
 

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even red lining or hitting stupid rpms. is doing your bike good. having remarkable fuel management in the upper rpm range. is it good too red line i think not if u know your bike u can kick the shit out of some one that red lines. i run my bike too 12000- no more then 13000 sometimes not very often just too releas pressure on the valves and cams and pistons. and i normally ride with hard shifts of 10000 and still kicks ass for thoes who run there up to red line...,

Well most all motors will fall off of their peak power up to 1500 RPM's from redline. Therefore its not necessary to go all the way to redline. If you do your actually falling out of the power and you will lose time on the track. I still go further than you i still think that you have more power to be had if you let your engine spin a little longer. At 12-13k your still making power. I do shift early also. But i have my shift light set at 14.5.
 

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You still need the jumpermod. I'm on my BB so don't want to type too much and get into it, but this is basically why...

The pciii deals only with fueling, whereas the jumpermod prevents the bike from pulling timing at 12k+ rpms.

When dyno'ing a bone stock bike the a/f never changes after 12k, so you know that the jumpermod is not messing with the fueling - it is retarding timing, my guess is because of the factory exhaust valve which happens to be closing around the same time to limit noise :)
 
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