According to my tinytach (reading half of my rpms
) 450 at idle 3250 at wot. my 03 Yamaha F90tlrb is taching 6400+ at full throttle w 2 aboard, average load. I have a Solas alum. 4 bld. 13x17 currently. I just adjusted the carb pickup timing and the motor runs better than ever. the throttle response is like a hotrod and must be going 40+ at wot, I know its not turning 3250. speed not verified yet. specified range is 5-6000. what pitch would help lower the rpms. boat is a 800lb 1860 G3 jon.