Kicker motor prop sizing

[SteveWilson]

Well my Johnson 9.9hp 4 stroke finally runs fairly decent and now I want to size the prop for what I want to do. My boat is a Lund Fisherman 1800 with a Johnson 140HP 4 stroke main, the 9.9 rides as a kicker for trolling. The current prop is a 9 1/4x9 3 blade, I believe it's a stock Johnson prop. I'm not looking for top end speed (which isn't on plane and is around 6mph), but am looking for a slower low end, better throtle response, and better boat control. At present without wind and waves the boat goes rougly 1.5 mph in gear at idle rpm. I would like to lower my low speed to 1.0 mph if possible.

Possible props are 3 blade 9 1/4-5 to 9 1/4-11. I've also looked at the Solas 4 blades which are 10-5 through 10-9. You're thoughts would be appreciated. I'm thinking that the 4 blade 10-5 might go slower and give me better boat control.

[Surface Tension]

Steve, I've never given propping a kicker motor much consideration. Now that you bring it up and listed the available props which btw vary greatly and you normally don't see that much of a choice for a 9.9. Dropping down in pitch should drop you speed at idle, how much it'll drop I can't say. It'll also bring your RPMs up at WOT which you probably won't be concerned with because the motors interned use is just trolling, so as long as you don't run it at WOT its fine. You brought up better throttle response and better boat control. Dropping down in pitch will help that out as well.