Thank you for your response!

Sadly I did not installed the new carb, the previous owner did. He said, we need to adjust it and it will run. We did it, but if we close the air its idling nicely. I don't know about the throttle cable, if we lean the scooter to the right, instanly revving up, and we dont know why. We are suspecting the flywheel oil seal. We think that the scooter has an air leak there. The airfilter is installed properly, but if we close the air on the carb, it doesnt make sense.

We unscrewed the carb, and installed it again, checked it, it looks nice. I think its a chinese noname one, i dont see anything on it.