Gori 2-blade vs Gori 3-blade

[Tony M]

Planning to replace my fixed 3-blade prop with a folding prop.  I'm likely to go with Gori, and wonder under what circumstances I should want to spend so much more for the 3-blade prop ($4,000) vs the 2-blade prop ($1,200).

We sail Sheba (Nonsuch 30C, #212) out of Nyack, NY on the Hudson River.  I started racing regularly again in 2016 in the non-spinnaker PHRF fleet, and hope to improve my performance in 2017 (hence the quest for less propeller drag).   Most of my other sailing is daysailing and a couple short  cruises each season(2-3 days).  I tend to single-hand often, so efficiency in reverse is handy when docking and mooring alone.  I'd say 90% of my sailing is day-sailing and racing, with little motoring or motor-sailing (though when going long distances I do both).

Would be curious to know opinions of other Nonsuch sailors, especially those who have used Gori 2- or 3-blade folding props.   Also, in addition to difference in initial price, are there any significant differences between the two Gori props as far as trouble-free operation, maintenance, fouling, or durability?

Thanks for any opinions, guidance, or suggestions.

Tony Martin
Sheba, Nonsuch 30C #212
(Westerbeke 27hp)
Nyack Boat Club
Nyack, NY

[Thor Powell Mariner's Cat V - 26C - North Channel]

Have a 2 blade on my 25 ..love it.  No issues at all.

[Tony M]

Interesting 2008 article comparing different props for drag, and for performance under power, based on tank tests.  Includes all 3 Gori models (2-blade, 3-blade, racing 2-blade), plus other popular models like Flex-o-Fold, Variprop and Autoprop.


http://www.propelspecialisten.dk/download/segeln_magazine_test_2008.pdf

[mark fagelman, MD]

I have a 3 blade flex-o-fold folder on my 33.
Minimal drag and great performance in fwd and reverse.

Look into it

mark fagelman

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[Robert & Diane Hindle]

When we purchased our 33, on board was an uninstalled Gori 2 blade. A call to the Gori dealer revealed that it was sold for a Nonsuch 33, with a 2003 Volvo rated 28HP@3200 rpm. My boat is a Universal and does not appear to have ever been modified.
Anyway, we have a Gori, seemingly in fine shape. The dealer (very preliminary) said the we might be able to change the blades but we’ll probably sell it.
Quite a mystery for us.


Bob Hindle
Haddam Neck CT
Jenny
1990 NS 33 #60

[Mark Powers]

Tony,

PYI which sells Maxprops, says that the three blade prop will work better powering against waves and wind and will be smoother than a two blade prop. They do not 

provide any data on this. They do suggest that a Maxprop will provide an average  10 to 15% increase in sailing speed over a fixed prop. The effect is most noticeable in light air. 

I believe in the PHRF rules your rating will be changed when you go to a feathering or folding prop.

I do not have experience with the Gori prop so can't help out with your questions on that front. 

On line you can find a comparison test of props conducted by Yachting Monthly which is an interesting read. http://www.yachtingmonthly.com/gear/folding-and-feathering-propeller-test-29807

Following the publication of the test the makers of the Kiwi prop had a letter exchange in which the makers of the Kiwi prop criticized the test methodology. They felt that Flexofold had gained an unfair advantage by sending too big of a prop and that while it preformed well in the test the larger proper would potentially damage the engine if used long term. 

Mark Powers

La Reina 26C

Vancouver, B.C.

[Joe Valinoti]

Bob: I might be interested in buying it. What is the shaft size. blade
size and pitch??



Joe

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[Robert & Diane Hindle]

Looks like 3 centimeter shaft

[Joe Valinoti]

Tony:  I replaced my 2 blade fixed with a Gori two blade and have never regretted it.  Not only was I about a knot faster under sail. but I pointed higher.  The 3 PHRF points I lost were well worth it.  Going to windward in a chop is not a problem nor did I experience it being harder backing. At 2800 RPM my W-27 gives me 6 knots in flat water.

Joe Valinoti
S/V IL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA

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[Joe Valinoti]

Thanks, Bob, but the blades are too big for my eng/trans combo.  I currently have a 12” blade size but it’s getting old .  I had tried the 13” and it did not allow me full RPM.  I suspect the shaft size is actually 1” or 25.4 MM

 

Joe Valinoti
S/V IL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA

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