I am currently in the process of putting a aftermarket exhaust on 05 zx6r, i was wondering if anyone has had a problem with bypassing the butterfly valve? or for that matter completely taking the unit off of the bike. does the ecu throw codes or does it not matter?

 

i put a yoshi pipe on my 05 and they give you a bracket that you bolt in when the wheel is locked at a certian point so the pipe co should be able to help you

 

If you leave the servo on and just remove the cable you wont get a error code. If you remove the valve you will lose some low and mid range power you will gain on the top though. In addition, you will have to get a power commander to adjust the air fuel mixture because you will run very rich with the valve gone.

JMO here but unless your trying to make a race bike I would keep the valve and just put on your slip on. That way you do not loose any low end and midrange power. True you will gain some HP but its all for the top. Most of street riders ride in the low and mid range not to often we run around for any extended length of time at 12,000 rpms. If your like me and do it any way you can always adjust your sprockets to give you more low and mid but then of course you loose top end speed. However, I don't need 185 anyway.

post some pics bro

 

notstock, if you take the valve out, you will get a fuel injection light. for some reason it makes the comp throw it. When i put my micron slip on on, i didnt leave the valve on and now i have a fi light. If im not mistaking, isnt the valve connected to the factory exhaust????? i cant remember i havent fuked with mine in a while. mine runs fine, smells like it runs a little rich, just dont have the $$ for a power commander.

 

On the 05 ZX6R the exhaust valve is in the undertail slipon. When you replace the slip on with and aftermarket one, you need remove the exhaust valve cables and pulley from the servo. A metal limiting bracket is installed on the servo. This bracket fools the ecu when the ignition key is first turned on. The servo will go through a sweep to check the servo and cable operation, if the ecu does not see this, then the check engine light will come on.

I do not know what will happen if you just remove the servo completely. My guess would be just the check engine light staying on. I have thought about doing this on my track bike to save a few ounces of weight.

A powercommander will be needed after any exhaust change, mainly to richen up the lower end to get back the low to mid range torque. It is amazing how well the stock exhaust does. I just hated the vacuum cleaner sound.

Mike

 

I realized I made a mistake in my previous post, you will get leaner not richer after the removal of the valve.
Not sure about the error codes on that bike, see green teams response, sounds like he has the same bike.
You want to get a power commander soon, running lean can cause engine damage. Check ebay for used ones and start saving