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BullsEye Vinyl
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Discussion Starter · #1 ·
My brother bought a used '07 R6. The owner of the bike said he "gutted" the stock exhaust to make it louder. Now the only other R6 I have ridden is my '08 and it feels much faster than his bike. Where my '08 seems to have power through the entire RPM range, his only seems to get going around 8k RPM and higher. I have no idea if an EXUP valve could make this much of a difference, but looking down through his exhaust, you can see that his EXUP valve is cracked nearly halfway open when mine looks as though it is completely shut.

First picture is his '07. The 2nd is my '08...






I was looking at buying the Jardine GP1 for my bike, but if removing the EXUP valve will make my bike feel like his, I'll be keeping the stock exhaust.
 

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you loose mid range power with no exhaust valve. My servo motor went at the track and we disconnected it. You need to tune the ecu now for the new exhaust. Some will get a power commander, I sent my bike to a race tuner to have the stock ecu reflashed and asked for plenty of mid range power. $750. So the answer is if you put on a new exhaust with no valve, you will most likely loose power. But if tuned properly, you will have lots of power gains. Maybe about 10hp with pipe and tune. You need to get a race header on there. The cat will hold you back.
 

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Because I Can
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How do you reflash a stock ECU? I thought Yamaha encrypted them?
 

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Go Ahead
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How do you reflash a stock ECU? I thought Yamaha encrypted them?
You don't. You run a piggy back like the PC3/5 or Bazzazz.

OP, just yank the valve, wiring and motor for the EXUP out. And no, it's not broken. It doesn't open until mid range to upper RPMs.

-Ant.
 

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You don't. You run a piggy back like the PC3/5 or Bazzazz.

-Ant.
You can get the stock ecu reflashed to a race ecu. It is a lot easier than a pc3/5 bazzazz and much more control. No extra stuff on the bike to go wrong.

So basically papawheelie blew $750 on nothing?
Actually I blew $1000, but he added quick shift to the tune as well. I would barely call it blowing it, I call it a sound investment. :rolleyes:
This shop prepped many race bikes for the AMA. Josh Hayes, Mellissa Paris, Ben Bostrom, to name a few. http://www.markbiltracebikes.com/
edit: yamaha is his specialty.
 

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BullsEye Vinyl
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Discussion Starter · #8 ·
You don't. You run a piggy back like the PC3/5 or Bazzazz.

OP, just yank the valve, wiring and motor for the EXUP out. And no, it's not broken. It doesn't open until mid range to upper RPMs.

-Ant.
Thanks for the replies. I disconnected the EXUP so that it was completely open. The first picture is actually his bike. You can see that it is already halfway open with the bike off. The second picture is my bike turned off. Mine is closed when the bike is off. That's why I thought his may be broken.
 

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yea, if you disconnect the cables, it will default to the open position. It will stay open. No matter if the bike is on or off. Yours will close if working properly while off.
 

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exup is a valve inside the exhaust can, not in the headers. It opens at higher RPMs to allow the exhaust to exit quickly. It stays closed during light throttle action to create back pressure for more low and mid range power. It also might have something to do with emissions. I'm not sure about that though. You asked should I remove it? I would. Also get a retune, or PC3/5 or something. I put on a full system, headers and can, and never tuned it. It ran fine on the track. I did notice very little mid range power. So if you do the header swap, you still have the choice to disable it. Mine died on it's own. The servo motor died. Common I hear, so I would remove it asap. BTW ghetto, I have an 05 header that I was gonna mod, but bought a full system before I worked on it. Make me an offer.
 
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