I've just been to the local friendly MoT station to have a look at the CO on my 900. My downpipes were both very blue (indicating running lean?) The settings were c1=2, c2=12. The CO readings were way off 3.5%, C1 was very rich and c2 was lean. To get anything like the 3.5% I had to set C1 to -40 and C2 to +50!!
This goes against what I have read on here but this was using a calibrated gas analyser. The bike seemed to run a lot smoother afterwards - I was expecting a lot worse given the difference in the units I had set but I haven't had chance to assess fuel consumption yet.
What I learned from playing with the settings was that messing about with = or - 2 units at a time had very little effect on the CO and I had to make large changes, 10 or so at a time, before any effect would take place on the CO readout. I was on their machine a good 25 minutes or so.
Just bought a K&N, will go back and try again when it's fitted.
I would say that unless you can play with the values whilst on a gas analyser, you are wasting your time. The local large dealership to me was no help, they don't have a way of measuring CO. They didn't know about the CO mod through the buttons.
PS: even with CO set to 3.5% on both, the lambdas were both about 1.2, indicating a very lean mixture. Anyone any comments? Bike is in excellent condition with no air leaks or misfires. I'll report back futher when I've played with it some more.
(Lambda of 1.00 indicates mixture is 14.7:1 - anything more than 1 is lean, less than 1 is rich)
Edited by strikemaster, 27 July 2011 - 08:49 pm.