Does anyone know how to determine the best prop for a Yamaha outboard,
8hp, short shaft on a 900 lbs speedboat.
Currently I use a 8.5(diam.) 8.5(pitch) N type propeller, but it feels
like the optimum rpm (5000) is not reached.
Any advice welcome. Thanks!

Call your local Yamaha outboard motor dealer, they'll look it up for ya.


Question for you..... I have a new Honda 8hp outboard. After buying it I let it sit for like 2 months before I started it. After that I found it was pretty hard to start initially... I might have flooded it though, but it took like 15 pulls and nothing... Then I waited 5 minutes and after that it started in about 5 or 6 pulls. After I warmed it up and ran it, it started without hesitation on the 1st pull. I was thinking that is normal when they sit for awhile. Have you ever experienced that with yours?

I think that's a quite common thing. My lawn mower has the same
problem, It sits in the garage for half a year and has problems
starting. It's caused by evaporation of the gas in the carburetor
leaving oil in the nozzle.