Small Engines (Lawn Mowers, etc.): go kart, dominator, cranks

Question
just got new tires, carb cleaned on go kart that's been sitting for a while. It cranks and revs when you push gas but doesn't go anywhere.  Got it from Walmart several years ago. It's an orange Dominator 126 cc.  Is it the chain maybe?  I oiled everything and it seems to be turning freely when pushed, just no pull when stepping on gas.

Answer
It might be that the clutch is rusted up.  Look and see that the chain is in place first, it should be around the gear on the clutch and the gear on the wheel.  If so, then remove the clutch from the engine and see if it's rusted up.  Let me know if that's not thew problam.  Thanks, PK.