I tried 32:1 but it was way too rich, I use 50:1 now and I havent had any problems. Easy way to think about it, I have a 5 gallon gas can, and on the back of my oil bottles it says 1 bottle per 5 gallons = 50:1. Itll usually say something like that on the back of the bottle. At the gas station, the easiest way to do it is put in the oil before you fill up, then fill the can halfway (or ask them to fill it halfway, its illegal to fill up yourself in OR.). Then put the cap on and shake it a bit, take the cap off and fill the rest. Shake it up a little more and its ready to go.

You shouldnt try to make premix IN the bikes tank. Dont worry, you wont run out of gas for a long time. I get more mileage out of my banshee than I did on my blaster. If you plan to get lost, get a grab bar with a fuel tank carrier. They usually carry 1 gallon or so, enough to get you back to civilization usually. I dont know whether they're legal in Maine though, I think you might be s.o.l. with that idea.