Good morning, it has been a while since I have posted. I spent time last summer repairing an 04 XB12R with the help of many on this forum. Thank you!

I recently picked up a basket case Buell in boxes and put the thing back together- 04 XB12S- K&N, D&D exhaust, Hammer 1275 kit, baro sensor with a tune from Buelltooth (open loop- 02 sensor reports but ECM is set so as it can not adjust lean). Heat cycles are done and it runs great so far.

My question: why would disabling the 02 sensor impact idling when the ECM can not respond to it? According to Dave at Buelltooth- he set it (the 02 sensor) up only to report signal.

More info: on initial start up, the bike would idle for up to 30 seconds then die (cough-sputter and die). The bike would then struggle to start. This repeated itself for two days. I reset the TPS each morning.

I was receiving 5 volts from the 02 sensor on the first startup. 0 volts on the second startup. Since the 02 was not reporting signal the 2nd day, I deselected it in exhaust setup (ECM Droid). And the bike started flawlessly ever since.

It runs a tad rich - which I am happy with until I get past the 500 mile mark. 218 lbs compression in the front and 200lbs in the rear.

Can you all provide me any thoughts?

One more detail- I replaced the 02 sensor on day 2 (I then reloaded the tune w the sensor reporting enabled) and still received 0 volt return to ECM. . I disabled the new sensor and the bike idled as it should.

Thanks for any thoughts.

Tim