CO Changes and Idle Adjust Do What?

I set the idle and CO today following the procedures described in a well done post elsewhere here on the forum.
I have two questions: a)what actually changes when I go plus or minus in the CO reading? Does plus result in a richer mixture, or what?
b) I found turning the idle adjusting screw ccw increases the idle but what is it doing? Is the throttle plate being mechanically opened or am I somehow causing the ECU to increase idle speed, or something else?

Making the co # higher makes the bike richer at idle and just above idle.

Turning the idle speed screw moves the throttleplate in the throttle body, adjusting idle speed.

My bike ran better with a higher idle and higher co setting enjoy.

Biglake wrote:

My bike ran better with a higher idle and higher co setting enjoy.

I went up 2 increments to 0 and raised the idle to the top of the recommended range (1650) and am pleased with the result too, particularly as it pertains to on/off jerkiness.

would u mind linking to said well done post on the procedure to adjust these in order?

mumixam wrote:

would u mind linking to said well done post on the procedure to adjust these in order?

Here it is  http://www.advrider.com/forums/showthread.php?t=538181&page=3