Re: prop for 85 115 yamaha 2stk
There is no "standard" when it comes to prop selection. Every boat is different which is why larger engines don't come with props as the manufacturer doesn't know what boat it ends up being installed on. However, 19 or 21 pitch will get you started. You make wide open throttle runs and note speed and rpm. If rpm is at or very near the upper rpm band, the prop is right. If its lower than specified you need to decrease pitch. If its overreving you increase pitch.
