Hi I'm new to RIB's and need some advice on prop sizes. I have a 4.8m Gladiator RIB with a Yamaha 60 FEDO. The current prop is slightly damaged and I was thinking of replacing it. Upon inspection the stamps on the prop are K21, and I have been told this pitch is too much and that I would be better off with a 13x17 or 13x19 pitch prop. I have no rev counter on it, so i'm not sure what revs its pulling, but the engine doesnt exactly scream. I tend to use the boat lightly loaded, ie no diving gear etc so what pitch would you suggest 17, 19 or 21????
Any info greatly appreciated, regards richard.