Re: Ideas how to contain carb spit-back
I concur with Bairdco. It's a 2 stroke and intake blow-back is normal. Either live with it or keep a rag handy, or go for a 4 stroke engine.
Some of the more exotic, synthetic oils. Opti-2 is an example will reduce the amount of oil in the intake by some degree but you'll always have it. Sorry, just a fact of life.
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