Re: 1989 Yamaha 70 HP vs 1985 Yamaha 90 HP
Very similar motors except the 70HP is 52 cubic inches,228 lbs., while the 90HP is 70 cubic inches, 261 lbs. The maintenance and condition of the motor is much more important than the age. If one of the motors has been used in freshwater only, then pick that one over a saltwater motor. Power-wise, either motor should be fine, depending on how fast/how far you want to go. I have an 18' Jon boat with a 90HP Yamaha and it's really more power and speed than I need or use much, but it's sorta nice to have the extra HP back there if/when you want it! Maybe for a bassboat like yours the 90HP would be better. Good Luck!
