Has anyone ever heard that you are only supposed to use a minimum of 89 octane gas in Yamaha F250's? I saw somewhere that it said to use only premium gas? It sounds like complete nonsense....but could it actually be true?
Not sure what F250's use, but you can find the owner's manual for your year and model on Yamaha's website and you can see what they recommend, it should be under the maintenance section, look for fuel.
