Re: spit back
It would help us to know what engine and carburetor you have but assuming you have a 2 stroke in-frame here's some info.
Some blow back out of the carburetor throat is nomal with a 2 stroke, piston ported engine but it sounds like you have a fuel leak. The fuel line that comes with the kits is notorious for hardening and cracking quickly. The barb fitting where the fuel line attaches to the carb can also be loose. The bowl gasket might be the culprit too.
Clean everything off well and start watching for where the fuel is coming from. A float that is too high will also cause fuel to seep. Always use the fuel petcock. Shut it off when the bike is parked.
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