SadbutTrue

A friend who owns/races an 06 ZX6R (same as mine) cautioned me that when installing a muffler, I need to be wary of the butterfly valve. He said the stock setup, the valve actually closes at high rpm (at 13k ish) to reduce noise. He says most aftermarket mufflers/exhausts get want to avoid that closing since its obviously not good fo rpower. However, he said that unless the muffler comes with a 'stop' system of some kind (i'm hazy on the details), the bike will throw a check engine light.

Questions:
1) Is this true?
2) Does this apply when installing a slip-on or only a full exhaust?
3) If I need to care, what parts do I need/procedure do I follow? If there are mufflers to avoid (that don't come with the stop), what are they? Should the muffler I get come with it?

Thanks!

Aeon87

Do the "Jumper Mod". Search for the DIY here on the forum. That mod basically converts your bike to Euro Spec and allows for the valve to stay open at all times without throwing the FI light.

OR, you could remove the servo motor altogether and get yourself the ServoBuddy/Servo Eliminator kit. Plug n Play.

yoshi

the valve shuts at the lower rpm to apparently make some back pressure for better torque, its questionable. more for noise emissions i think.
removing the silencer removes the valve, you dont need one

SadbutTrue

Got a link? I've done jumper mods before on my old Sv650, shouldn't be too hard... but a plug and play kit might happen sooner

Thanks!

SadbutTrue

anyone got a link to the kit/DIY jumper mod?

givuhcky22

sad,
lift seat,
find this


pull off tab, exposing 4 holes.

connect top left to bottom right as shown:





then put cap back on. finished.

SadbutTrue

sweet. is that just any old copper wire or anything specific used to cross the jumpers?