Since your fuel is just fuel go ahead and add some TCW-3 (2 stroke synthetic grade) or MMO guess your fuel in the tank and add enough "top oil" to get a bit richer than 100:1, it won't smoke and it's also very good for the rings while keeping oil on the valve stems, a good thing.
I ran my engine with TCW-3 for over 30 years and didn't loose any performance or a drop in compression numbers in fact they did go up a bit.
Dave Neptune
