gori prop

[agoodman]

Has anyone attached a two bladed Gori folding prop to their atomic 4? If so what can y ou tell me about it. I currently have a two blade martec folding prop and reverse is pretty bad. With the Gori prop did you notice that you could decrease rpm and still maintain the boat speed of the martec? Thanks for the responses.

Al Goodman
C&C 35 MKII
Skylark

[SimonV]

I have a Kiwi prop, and highly recommend it but it does have serious reverse.

[Jeff_H]

I had very poor dealings with Gori on my prior boat. The prop's hub was very unreliable, Gori was very difficult to deal with (you had to pay shipping to and from thier headquarters in Denmark even on warrantee claims) and ultimately they refused to stand behind their product. Personally, I found that Martec to make a better product, far more reliable, and certainly provides better factory support.

Friends don't let friends by Gori or Flexifold.

Jeff

[sailingdog]

From what I've seen, MaxProp and Kiwi are pretty good and the companies who make them stand behind them. Of course, I don't use either currently... since I don't have an inboard on my boat.

[Faster]

Regardless of brand, what is going to make your prop work for you (and determine the rpm vs speed) is going to be a function of prop size and pitch, more than "make".

Any regular folding prop is going to have challenges in reverse. The Gori's advantage is that the blades are geared together so both will always open. There's nothing as scary as the first time your martec only pops one blade open - feels like something is trying to rip the strut out of the boat.

Sounds like Jeff's warning re: Gori is be worth paying attention to.

The more expensive Max and other feathering props are much better, but at considerable cost. The Kiwi prop has had some good reviews but is an odd looking beastie.

If you're not racing, consider the Campbell Sailor prop, a low-area (narrow chord) fixed blade prop with good reverse performance and with drag somewhere between a michigan wheel and the various folders/featherers.

[Fstbttms]

Originally Posted by Faster

The Gori's advantage is that the blades are geared together so both will always open. There's nothing as scary as the first time your martec only pops one blade open - feels like something is trying to rip the strut out of the boat.

FYI, Martec sells two models of their 2-bladed folding prop, the "Eliptec" (free-swinging blades) and the "Geartec" (geared blades).

[Faster]

Originally Posted by Fstbttms

FYI, Martec sells two models of their 2-bladed folding prop, the "Eliptec" (free-swinging blades) and the "Geartec" (geared blades).

Thanks, Bottoms.... didn't know that. Good to know that Martec is an option there if the Gori service issue is troublesome. btw- any comment on that?

[Fstbttms]

Originally Posted by Faster

Thanks, Bottoms.... didn't know that. Good to know that Martec is an option there if the Gori service issue is troublesome. btw- any comment on that?

One of my clients is a Beneteau dealership here in the Bay Area. They love the Gori props and install many of them as an option on their boats. Have never heard of any service problems with the Gori sellers back east (ABI). I do know that I can get Gori zincs online for about half what ABI wants for them.

[Valiente]

I removed a Michigan Wheel 12 x 6 fixed two-blade from my 7/8" shaft attached to a rebuilt-in-2005 Atomic 4. The boat is a Viking 33, about 10,000 lbs. The new prop was a Gori 11 x 8 two-blade folder that had spent four seasons on a C&C 35, also with a 7/8" shaft and an Atomic 4. I cleaned it and used the right type of Lock-Tite on the allen key bolts and I keep it lubricated in spring and fall. I do not otherwise coat it, but I do use a donut-style zinc on the shaft. I have never seen much fouling on it, nothing a Scotch-brite pad and some Brasso hasn't fixed.

Sorry to be the happy customer, but the Gori has performed exceptionally well for me. I bought it primarily to reduce drag while sailing (although I don't race, I like to cruise like I do), and in this it succeeded entirely: I figured I have gained approximately 0.4-0.5 of a knot in speed with similar sail sets and wind speeds when compared to the days of the fixed prop.

A few comments:

Any folding prop is primarily designed to be slippery, not to drive the boat when motoring to perfection. This is why I'm installing a four-bladed feathering prop on my steel cruiser: the application is different. With the two-bladed Gori, I find I push the engine about 100 RPM more to get the same speed in flat water than with the fixed blade. On the other hand, cavitation at top speed is reduced, probably due to the squared-off blade tips.

Shifting is tricky because you have to go to neutral and then GUN the engine in reverse to deploy the blades. This adds about two seconds to this maneuver. Lucky I dock this boat in neutral as much as possible.

Prop walk is somewhat less. I don't know why.

A notable difference: My "dead slow" speed with a fixed blade on the direct-drive A4 was about 2.5 knots, which is why I docked in neutral, just aiming and coasting. With the Gori, dead slow pushes me at 1.7 knots SOG, which is much better for docking, as I can stay in forward closer to the dock in case I need to rectify errors.

Normally, I motor out just to get head to wind at five knots or less. The Gori pushes the boat fine here, but as with any folder or feathering prop, it's when you switch off that you notice the difference. This boat is now being raced by its "foster parent", and she loves it.

Your mileage, evidently, may vary. It cost me $300 and so far, it's provided that in enhanced sailing experiences.