Small Engines (Lawn Mowers, etc.): Honda motor, speed jet, honda motor

Question
I have a Honda G-200 5hp motor. This is to be used for a Go-Kart. The motor will run but "sputters" on idle,,For it to run the choke is closed and the gas is on full. I replaced the spark plug,, and installed a different carb. This motor has a fuel pump and a carb with a float. It also spits gas out of the carb-intake..

Can you help me with this?

Jim

Answer
It could be a timing or valve problem but my guess is the carburetor is too large.

Check the ignition timing by removing the flywheel and inspecting the key.  

Can you lean the carburetor mixture or is the carburetor a fixed high speed jet?

Let me know.
Eric