Surging due to exhaust mods?

[TrailingJack]

I own a '96 1100GS that exhibited no noticable surging when I bought it used in '01. It had a Staintune exhaust w/cat installed when I bought it. Over the winter I had a local guy (whom I trust with all things mecanical ) fabricate a pipe to eliminate the cat, complete with oxygen sensor located in the same spot as stock Staintune. I now experience noticable surging between 3k and 4k rpm along with occasional backfiring. Sounds like a lean condition but the plugs look normal. Anyone have experience with something like this? Solutions? Techlusion 259?

[cat0020]

Since you already have the cat and O2 sensor eliminated, the fuel injection map may need to be changed, you might need a Power Commander instead of Techlusion.
I would try using the Techlusion 83i (older version) first instead of 259.

My 02 R1150RS with 22000 miles, EOM exhaust.. I just installed a Techlusion 83I and unplugged my O2 sensor at 21000 miles. I never thought that I had a surging problem before but the difference is dramatic. Just make sure you have someone set up the Techlusion with a voltmeter.

[TrailingJack]

Cat, thanks for the info, but I probably wasn't too clear about the setup. I still have the o2 sensor installed in the new pipe. Should I have eliminated it?

[cat0020]

If the cat is gutted out, I think you would have to disconnect teh O2 sensor, or at least trip the EFI brain that you are running a closed loop. You surging might be related to the EFI brain trying too hard to compensate for the gutted cat.
Yeah, try rinning the bike with the O2 sensor disconnected, and re-route the O2 sensor plug.

Check out this page to make yourself a CCP jumper to disable to O2 sensor.

http://www.ibmwr.org/r-tech/oilheads/tl_instl/techlusion_install.shtml