Craig,

I generally mix my fuel as I use it. I have a smaller 2 gallon fuel can I mix in. So just before I go out for a session, I will mix a gallon or so at a time, put it in the bike and run the session. This way I don't have any left over pre-mix (or as little as possible) at the end of the day/weekend.

The leftover useally goes in my crappy push mower (which after years of abuse, still starts right up and runs strong!). Also when using A747 and race fuel, you wll want to drain your tank after the day/weekend. Don't really want to keep it in the tank for extended periods of time.

Oh and also you will want to drain your carbs as well when your done.