Star tron, Sta-bil, they both work pretty good. Honda and Yamaha both marketed their own variety of gas stabilizer. If in doubt, use a little extra, just don't go overboard. In the springtime or whenever you get your bike out of "storage", drain out at least half if not all the old gas. The gas you put in the bike for storage is there to keep the carb from gumming up and keep condensation out of the tank. If you know you absolutely, positively will be draining out the old gas you can use a greater amount of oil(20:1, 16:1 ?). The reason for more oil is that if/when the gas evaporates it will leave behind an oily residue. The oil won't turn to "varnish" and the extra oil makes it difficult for anything to stick to the brass or aluminum. On the subject of octane booster, Toluene will raise the octane but it isn't the same as what you find in mothballs. Gasoline typically has some Platformate/ Reformate that is used to bring up the octane, unfortunately it also has a very low vapor pressure. Refineries also use something called FRC, Full Range Crack, a product that comes off the "Cat Cracker", which is one of the highest octane blends. Regular unleaded has some and premium has a lot more. As long as you use some type of name brand stabilizer you should be fine.
