Crap. Those are some expensive mods.... FML. I wish I'd read up a bit before having the cat gutted. I'm still going to try a tuner any just to say I tried everything, LOL.

 

If the cat is already gutted, its not that expensive to weld in some 18mm bungs. U can go cheaper on a tuner, I went with thundermax for the simplicity of not needing to dyno now or in the future if I do cams and headwork. The t-max nay sayers will say u can't adjust the timing, but low and behold I can on mine. I have paid for sert and powercommander and dyno time on two other bikes and the price for one of those bikes= t-max. So basicly it was my preference to go t-max this time around.

 

Interesting - can you help me understand how the 18MM O2 sensors would help me in my situation?

Thank you,
Tim

 

They will aide in an autotune type of tuner, such as tmax or pcv autotune. Otherwise they are not necessary. The autotune type use 18mm wideband sensors.

 

It sounds like to OP has an exhaust leak at the header flange. He should be running leaner with the cat removed, not richer. Introducing air into the exhaust stream from a leak is going to make the O2 sensors show a false lean condition. The ECM is going to add back too much fuel in an attempt to compensate to bring the bike back to the target AFR. However, this is a false reading due to the air leak.

It is possible it could be the O2 crosstalk issue mentioned but check the obvious possible causes first. If it does turn out to be crosstalk you could try relocating the bung that's in the collector to the pipe.

Make sure you put the O2 sensors in the right place - gray for the front and black for the rear. And get that tuner since you're going be running lean once you fix the issue.

 

I have a 2011 Street Glide that's going to get a Fuel Moto head pipe & a Dyno tune. This new head pipe comes with both 12mm & 18mm bungs.

Would there be any advantage to using the 18mm bungs, as opposed to the stock 12mm bungs?

Thanks

 

I wondered the same thing about 12 vs 18.

-Tim

 

Can't speak for everyone, but my bike runs BETTER with the cat removed. I have stock A/C, Wild Pig muffs (with 1 3/4 inch baffles), no tuner. Granted, I only have a few hundred miles on since gutting it but so far I'm glad I did.

 

not on a 2010 or 2011 unless you have a tuning device that uses wideband sensors that require the 18mm. On 10's and 11's the 02 senors are heated and will not last long if you put them up where the 18mm bungs are.

 

Get a fuel Moto power comander, it dosen't use the o2 sensors.