1978 KZ200 Idles very fast. Help

OK - I'm very new to all of this. I have taken a small engine repair class - so I know some basic concepts. I have cleaned the gas tank, cleaned and rebuilt the carb and up until last night the motorcycle was running fine.

So I had it painted and last night I picked it up from the guy's house. In the 20 mile drive home it idled a little low - I stalled out a couple of times at stop lights, but otherwise the bike was running smoothly . So when I got home I tried adjusting the idle and thought I'd gotten everything perfect.
However when I went to drive the motorcycle this morning, when I came to my first stop a half mile from home it wouldn't return to idle. I tried figuring out what was wrong and readjusting things.. but I just can't seem to figure out what's going on.

I had to keep shutting the power off at long stops my whole ride to work..

Any insight would be greatly appreciated.

Racing idle may result from an air leak where outside air is being ingested into the mixture delivered by the carbs.

Possible sources of such air leak could include such things as old hard worn-out cracked carb holders, or poorly sealing vacuum plugs (caps), or loose clamps around the carb holders, etc.

Might also be caused by a throttle cable issue.

Or a too lean pilot circuit.

Good Fortune!

I would remove the tank and carefully check the throttle cable routing. If the guy painted the bike he would have removed the tank, so it's possible he mis-routed or pinched a throttle cable when he put the tank back on. Ed