Best prop pitch for twin motors on a semi rigid?

[Bruce M]

Hello all,

I've recently acquired a Gemini 505 with 2 50hp 3 cylinder Yamaha's on the back.
Currently they are fitted with a 12 pitch on one, and 15 on the other!
What is the recommendation for this set up?
Boat will be used for basic fishing round the point etc, and towing small kids on a tube on the breede,tierwaters erc.

Thanks!

 

[rianc]

Hey Bruce. The 12 pitch will serve you well with ample of torque, for towing tube around. The 12 pitches will have you on the plain in no time, but top speed will be compromised and over revving could become a problem if you don't keep an eye on the rpm gauges.12 pitch is also good for running in the saline sea water, much better replacement. But I would prefer the 15 pith for inland water for all opposite reasons mentioned. Trust this could get you thinking. Lets see, some very experienced people on the site.
Good luck
Rianc

 

[Bruce M]

Thanks Rian, yes I'm thinking of going for the 13's because I have a spare 13 that came with the boat and is in quite good condition. The 12 I have is worse for wear. Also, having taken it out with the mismatched probs I don't feel she will struggle, I reckon 2 off 50's is a healthy amount of power for a 5m duck.

 

[willem wikkel spies]

they props should be the same
why 2x different props were fitted is unknown.
13 inch props would be best, considering weight wise.
a 12 inch prop ...well i dont think that the boat with all crew will overload it and thus 12 inch is not needed.
maybe money was an issue so y the fitment of 2x different props.

yip 12 inch for tube pulling yes hell, y not!!!!