Re: mixed gas ok to use in 4 stroke
Burning 2-stroke oil, which is designed to burn cleanly to begin with, won't be a problem if you mix it in at a highly diluted rate,like a 1/2 gal of 50:1 to 9 gal of pure gasoline. That would be a mix of 1000:1. It'll pass through anything just fine at that concentration and would be no different than using something like lucas fuel treatment, marvel mystery oil, or fuel injector cleaner at their recommended dosages which range around 100:1 to 500:1. But I would not just pour a 50:1 mix into an empty tank and run a 4-stroke at 50:1, nor let it sit for any length of time (at any mix rate) in the tank and especially in a carb because the chances are higher it'll separate or gum up and cause problems.
forgot to mention, 2-stroke oil has some zinc and phosphorus in it. Even though it's a minute amount compared to engine oil, burning 2-stroke oil routinely at any rate will hinder and eventually kill a catalytic converter so you don't want to use it as a "regular" fuel additive on an auto.