Honda Aero running lean! How do I fix?

[Guitargraham]

Howdy! I recently bought a Honda Aero 50 (1985) and I got it to run (after spark plug new batt new airfilter) but when I give it gas, the engine revs up, but won't come down!
I think this means it is running lean.
I cleaned the carb thoroughly (ultrasonic) but this issue persists.
It will start easy, with a little throttle.
What's going on?

Thank you for your help in advance.

[hondafan]

Is it revving eeal high? Sound like either the throttle cable is not moving freely or you didn't reinstall the carb throttle in correctly. If you install the slide backwards it will cause this.

[Guitargraham]

Yes, It does rev fairly high, but I did install the cable correctly and checked it already.

[martynkim]

Throttle cable adjustment? Check the plug for color this will tell if it is lean.

[Guitargraham]

Here's a picture of the spark plug... Doesn't look "lean" to me.

By the way, bike in the background is a nt650. Any other hawk riders around here?

[mmeadows]

your plug looks coco brown so i think your okay. i know that the position of the color line looks good. not that i really know what that means. i know a plug expert on here will chime in since you took such a nice pic.

uncontrollable revving and a lean conditions are not usually synonymous. take a picture of the position your slide is in, when you put it back in your carb. it only goes in one way.

i live in tigard if you really need help.

[JJ Joseph]

when I give it gas, the engine revs up, but won't come down!

It doesn't sound lean. More like the throttle slide isn't assembled correctly.