I got a two bros pipe for an 06 f4i...i got the CA model...I am putting in an o2 sensor bypass, so what do i do with the hole in the mid pipe? Im not sure of the size for a bolt but is there a treated type? does it need to be welded? better off making custom pipe for the mid pipe?

 

I don't remember the bolt size off hand. You could just take the mid-pipe into a hardware store and match it up with a bolt size, just get the shortest one the matches the treads.

 

I'm pretty sure you can go to an auto parts store and get a plug for it. I'm not sure if the bung on a bike is the same size as a car, though.

 

Try some old spark plugs in the hole, I'm sure some will have the same thread.

Alternatively just measure the thread on the O2 sensor. Measure the gap between threads to get the pitch and measure the width. i.e. P and D below:

When measuring P, if you don't have a set of vernier calipers then measure several threads (i.e. 10) and divide the total length measured by the number of threads measured.

 

Thanks everyone...two bros told me to just put the o2 back in the pipe, though it will not be active and just zip tie the wire...but i dont know if i want wires zip tide together around the shock and rear tire...

 

send me the midpipe!!! Ill send you mine that has no hole LOL!!

I've been trying to get a bung welded into my midpipe forever, never get the time or the right welder.

I also have the 06, and have another thread where you see the MPG goes down a lot without that damn O2 sensor!!

If I were you I would utilize the O2 sensor...

I had mine deleted and want it back!!!!