if a weedeater or chainsaw seizes, it is likely due to someone inexperienced with 2strokes refilling the gas. i couldn't count how many times i've heard people say that they told whoever 'here this is the gas for this, and here are extra bottles of oil for future use.' kids will grab any gas to run on, i am even guilty of this. 2stroke in a four, it ran so no prob. but i haven't ever tried to run straight gas in a 2 stroke. ffr (for future reference), 50:1 is 50 oz. of gas to 1 oz of oil. the first number is always the gas, the second is the oil. the little premix bottles will say all sorts of ratios, and though two will have the same ratio, they will not have the same amount of oil for a single gallon of oil.