I was looking for an answer to the question in the OP.

How do I know where to set the idle speed? I cleaned my carb and now it wont hold idle. Starts, stays on if you hold the revs up, idle mix screw started at 1 1/5 turns out. Its probably at 2 turns out currently.

I'm thinking trying to turn the idle speed screw out and seeing if this will help it hold idle.. might have moved the original setting when cleaning.

 

So just went thru this with my KLX110.... set the fuel screw to 1-1/4 turns out.... start bike and let it warm up.... once warm, twist the throttle to get up to about 1500 rpm and while holding it, adjust fuel screw. Turning out adds more fuel, turning in leans it out. What you are listening for is the change and eventual drop-off in RPM... at peak RPM it is a perfect fuel to air ratio. Most people then will turn the fuel screw in 1/4 turn to make it run slightly lean. Let off the throttle, then adjust the idle to the desired speed.

Note, there are many other items that need to be checked before doing this. Make sure all fittings are tightened and that the gaskets are in good condition. I found an air leak on my bike that make getting the idle mixture right impossible. Once the air leak was fixed, bike idle setup was a breeze!