Dual thrust prop on partyhut

[froghill]

I have just down pitched my Yamaha F115 tlrb from a 19 pitch to an 11" dual thrust prop. This was a Craigslist find and for the price it would be , at least be a good back up prop. Found that on 28' Partyhut, I had same top end and it actually brought rpm to 6100 for first time. My question is am I just hitting over rev limiter & will this have any effect on gearbox? not sure ratio in lower unit.

 

[steelespike]

The promotion says for T50 and T60 With high thrust gearing.Don't know if the gear case is the same size as the 115?

 

[froghill]

That's all the info I could find. So far,performance is certainly acceptable, I'll have to see specs on those gears vs mine b

 

[froghill]

F-50,60 have 1.85:1 ratio, F115 is 2.15:1, so they are different.

 

[jimmbo]

Dual thrust?

 

[steelespike]

"Dual Thrust" refers to improved thrust in forward and in reverse. reverse is impressive as reverse is sometimes ineffective.

 

[jimmbo]

I do recall seeing a prop that had an extra ring around the diffuser/converging ring. At first I was wondering if he had meant a vari-pitch prop