# Prop for Yamaha F25?



## rscottp (Mar 27, 2014)

I have a 2005 Yamaha F25 4 stroke with a chewed up prop that needs to be replaced. The current prop is 9 7/8 x 10 1/2 and I am wondering if I should increase the pitch a bit. Considering a 11 1/4 of 12 inch pitch prop. My boat is a 16' Lund, I am guessing that total weight including me and the dog is somewhere in the 850 lb range. I do not have a tach but the boats max speed last year was 22mph, boat was at least 150lbs more last season before modifications. Thanks in advance.


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## lckstckn2smknbrls (Mar 27, 2014)

You really need a tach to know what rpm's your turning. Some boat shops have props you can try before you buy.


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## turbotodd (Mar 29, 2014)

I don't know your boat and your motor, but 22mph seems slow even with a stock 10 1/2" prop. Perhaps it was a little damaged when the speed was tested? 

Without a TACH, you're shooting blind.

That said, on the boats I've messed with, all aluminum flat bottom and slight semi-V duck/jon boats, the factory 9 7/8 x 11 1/4" prop works extremely well on the F25's. I use one on mine. I bought an expensive Turbo, then had some cupping put into it and some other work done to it, and guess what? It performs exactly the same as the factory $130 aluminum Yamaha 9 7/8 x 11 1/4" prop. The 11 1/4" is a stock 2 stroke prop. The holeshot will suffer just a shade but most don't notice it. I notice it more when I'm loaded heavy. 2 of us in the boat, the big dog (90 lbs), tackle, 3 bags of ice, ice chest full of fish, 15 lb anchor, trolling motor, battery, and all her junk (phone, iPad, drinks, etc) That prop works well on mine. I've seen 6180 RPM last weekend in good heavy cool air, real close to 30 MPH on my rig. Most of the time between 28 and 29 favoring the 28 and around 5900 to 6000 RPM which is right at the top of the maximum for that motor. I've been wanting to try a 12" but haven't found enough left over at the end of the month to buy one (and the dealer won't let me "try" one, unfortunately).

putting a tach on it is simple. See the post: https://www.tinboats.net/forum/viewtopic.php?f=4&t=4391&p=315867&hilit=tach+bracket#p315867


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## rscottp (Mar 30, 2014)

Thanks for the insight. When I got the boat it had a Johnson 25hp 2stroke on it and it topped out around 24-25mph, when I switched motors I went down to about 22-23. At the time boat was full of waterlogged foam to the tune of probably 400lbs which I have removed. The last few years prop has gotten pretty chewed up so that could also account for the slower speed. I don't really run at WOT anyhow but think I will go up a little in pitch on the new prop. Do you think SS is worth the extra $$?


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## Boat2fast (Mar 31, 2014)

If you are on the edge, a little too little is better than a little too much...pitch.

You need a tach to find the right prop. It doesn't have to be a permanently installed tach. A small trouble shooting tach is fine to get the boat/prop dialed in.


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## rscottp (Mar 31, 2014)

Thanks, thinking of going with a Solas 11" pitch prop. Is the extra $ for SS worth it?


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## Boat2fast (Apr 1, 2014)

I generally do. I don't ever want to let a MPH get away.

Solas props are pretty cheap to buy. I have had decent results.

Factory props have always been the way to go in the past. 

Don't even consider a SS prop for shallow or unknown waters.


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## turbotodd (Apr 1, 2014)

rscottp said:


> Thanks, thinking of going with a Solas 11" pitch prop. Is the extra $ for SS worth it?



With Solas? No. They are paper thin. They are a chinese prop and bend easily. Good thing is that they bend back easily too. For the money, an aluminum is probably about the same prop with almost the same characteristics. I've sold hundreds of Solas 11" props at work, and nobody ever says they're "stellar", just a stainless version of a factory Yamaha aluminum prop that bends nearly as easily. It's been my experience that the Solas 11" runs identical to the factory 11 1/4" aluminum prop. Only difference is that it's polished stainless instead of white, lot of guys like that.

I like the Turbo Hotshot 11" myself, before I spent $200+ on a Solas. At least Turbo is made here in the states and much more accurate in terms of keeping all 3 (or 4) blades the same. I've seen them built...they melt a LOT of props down because of general errors. Takes about 30 days to build one prop because they have a strict quality control. I run one on my older F25 and love it. Great holeshot great midrange decent top end (top end same as 11 1/4" factory prop, right around 29 mph roughly). 31.6 is the best I've ever seen, and don't expect to see air and water conditions like that in a long time. I might try a 12" to see if the little F25 will turn it one of these days, but I need to work on the setup a little more before I go playing with props.


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## rscottp (Apr 1, 2014)

What about the aluminum solas prop?


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## turbotodd (Apr 6, 2014)

[url=https://www.tinboats.net/forum/viewtopic.php?p=347122#p347122 said:


> rscottp » 01 Apr 2014, 18:31[/url]"]What about the aluminum solas prop?



Thick blades. They have to be-they're cast aluminum. Thicker means there's more drag. I have run a couple Solas 4 blade aluminum props and they were ok. I liked the smoothness and the ability to get on plane quick and stay on plane "easier"; but lost some top speed. About 3-5 mph is what I lost over the Turbo 3 blade hotshot 11" (solas aluminum 4 x 9.9 x 10). But it sure ran smooth. That was the most impressive aspect. I did break a blade completely off of the barrel on one of the 4 blade Solas AL props. Hit a submerged stump, not real hard but I guess it doesn't take much.


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