Another interesting note: Yamaha outboard marine folks say that if an engine is stored for winter you should not fill the tank, it should be as low as you can get it. Their engineers says that the octane level will drop
substantially, low enough to cause major engine damage in the spring. Also, there is almost no way that significant moisture can accumulate enough to harm the engine especially with today's additives and since most tanks are plastic now, rust should not be a problem.
This was news to me, since I have always made sure the tank was full at the beginning of winter.. Confusing at the least, but since I start and/or ride my bikes each month during the winter I haven't worried about them. However, I do follow my Yamaha boat dealer's directions on my outboard.
ScoutDogMan