Adjusting CO levels GEN II vs. Barbarian Mod

[RaYzerman19]

Question.... if you vary the CO settings, doesn't the ECU get it's information from the 02 sensor, then adjusts the FI accordingly? OR is it simply a hard programming? Those of us with PCIII or V have (I assume) unplugged their 02 sensors. Anyway, just wondering if this is true or not. If not, would it be appropriate for anyone with a PC to modify their CO settings? Anyone done it and notice any goodness?

Adjusting the CO values offsets the base FI map in the ECU; adjusting the map either up or down in a range from +128 to -127. Any feedback from the O2 sensor would be on top of the CO trim. The PC III then intercepts the ECU FI signal going to the injector and replaces it with a fuel injection volume that was tweaked by the PC III map.

The PC III EX still recommends disconnecting the O2 sensor.

Thanks for the info.... so perhaps a little CO tweak might help a bit even though I have a PCV with 02 disconnected... I'm hoping to preserve the good fuel mileage using the map provided by FuelMoto, and didn't want to richen up the map much more.... but then again, that's what the CO setting is causing it to do anyway, I suppose. I can live with what I have, but maybe later when I will want it better.......

 

[Fred W]

I don't think so.

My impression is that when (if) the ECU goes closed loop it will over-ride any PCIII or PCV map adjustments.

But the CO settings do definitely effect the closed loop operation somehow. So, I think that the CO settings actually modify the "target" of the ECU when in closed loop. The Power Commander just seems to modify the base map.

 

[UselessPickles]

so perhaps a little CO tweak might help a bit even though I have a PCV with 02 disconnected...

The map on your PCV was most likely tuned on a stock bike without any CO adjustments. If you want the map to cause your bike to run the way it intended to run with that map, your bike must match the bike that the map was tuned for as exactly as possible. Put the CO settings back to stock, unless you have the proper equipment to measure its affect on the air/fuel ratio and torque output of the engine throughout the range of throttle positions and RPMs (i.e., a dyno). But if you have that equipment, you would want to be adjusting the fuel map rather than CO settings for finer control anyway.

 

[Jon]

To answer the question regarding the BJM/CO settings and the updated ECU - I have a '07 FJR. I did the Barbarian Jumper Mod and CO adjustment (I wrote the article on it that's in the Bin-o-Facs) and then had the dealer replace the ECU. The ECU swap had no effect on how the bike ran. The only change was, as mentioned in a prior post, to how frequently the computer did its sampling. I continue to run with the CO settings +5 and have a much smoother throttle response.