I replaced my grandson's Chinese atv motor with a 110 cc.
The engine cranks but runs wide open. First time and only time I cranked it I had to pull the spark plug wire to stop it to keep it from running wild across the yard.
Any ideas of how to adjust it (carb or throttle cable etc) or what I need to do?
Thanks

 

The carb slide was probably not installed correctly. You should be able to hear the slide hit the idle adjuster screw when you let off the throttle. If not pull the cap and make sure the slide goes all the way down in the carb. You may have to turn it until you get it lined up.

 

that's what it sounds like, take the slide out, you should see notches on the slide and **** in the throat of the carb. you'll see one is lower than the other. SO, match the slide and you'll see the slide go all of the way down. also, i'm sure you've done this, but please make sure your return spring on the slide is good and your throttle cable is still anchored inside.. once you visually verify the slide is all of the way down, you should be good to go. if not, holler back at us........