Most small engines that require gas-oil mixtures now call for 50:1. 40:1 used to be the norm, but the they've lowered it to improve emissions, if not necessarily improve lubrication.

The local Sthil dealership tries to sell a six-pack of "2-stroke" oil with every purchase. One bottle is enough to treat one gallon of gasoline. I did some quick math and determined that a six-pack would hast me about 100 years. My neighbor wasn't so smart, and she bought the six pack. Her husband is too much of a knucklehead to mix the gas and oil properly, so he started buying the pre-mixed stuff. He gave me five unopened bottles. I gave two bottles (worth about $5) to a landscaper who works in Bubba Estates, and kept three.

I have a Stihl edger and hedge clipper that use gas-oil mixture. But, they're both 4-strokes.

The "2-stroke" oil probably contains ZDDP, which is a great anti-wear agent, but it harms catalytic converters. They've stopped putting it in motor oil.

The more you dilute it with pure gasoline, the better off you'd be burning it in something that doesn't take mixed gasoline-oil. You risk fouling your spark plug, but no more so than it would in an engine that uses mixed gasoline and oil.

Non-ethanol gasoline is readily available in Bubbaville Beach. Bubba buys the stuff 100 gallons at a time for his boat. The Mobil station across the street from Bubba Estates sells the stuff out of one of their main gas pumps. I can use a credit card and not even have to go inside to pay. I buy less than one gallon at a time, and I make a point to burn every drop of it within 30 days before I buy more.

At the end of the growing season, I put every one of my gasoline-powered implements of destruction on my driveway, start them up, and run them dry. That pisses of some of my neighbors, especially the guy with a Tesla. OFW.