If it is the black carb adaptor from CH, I'd recommend trashing it. Mine would vibrate when the engine got to speed. I like the folks from CH, but the black one they sold was a disappointment. They have come out with a new design, but I am not familiar with it.

I have been running this engine for a couple of years. After my initial poor results with the CH adaptor, I changed to a g-10 adaptor I made myself per RCIGN1's instructions. It and the engine has been bulletproof.