Re: what ratio do you run your yammy at ?
Most folks use the 50:1 ratio....I think Yamaha tried the 100:1 ratio for a period of time, but although 100:1 provides barely adequate lubrication, it didn't provide much oily film corrosion protection for internal engine parts....I have used the 50:1 for many years in several Yamaha outboards with excellent results....If your brother wanted to get technical, he could consider splitting the difference at say, 75:1....but I doubt the motor is going to be able to tell the difference. Good luck!
