Prop Advice

[kwaskow]

Running a 2005 Stratos 386XF with a DF140 and Al prop 19" Pitch. Thinking of going SS and 18" Pitch to try and eek a little more hole shot for pulling my kids up on skis.. This one is $332, which seems reasonable....any advice is appreciated!

http://www.bikebandit.com/oem-parts/...FQaJaQod5iII_A

[Harper]

Assuming you're getting the correct RPM at WOT with your present prop, the SS that you're considering should be fine. Since it has less flex than the aluminum now on the motor, the 18" pitch SS should not be much different than 19" aluminum. I'm not sure what your results will be as to hole shot performance, but I expect you'll see a little better performance.

[Moonlighter]

What revs are you currently achieving at WOT?

It needs to be 6000-6200 with the DF140 in order to get optimum speed, economy and hole shot. If you are under that range then a lower pitch will be required.

If you are in that range at present then, as Mike said, the SS prop you are considering should generally give you better performance out if the hole, assuming also that it is the same diameter.

[kwaskow]

Presently at WOT I can get ~5900 RPM. Maybe I should even go as low as a 16 inch pitch. Is 18SS the same as 19AL?

[Moonlighter]

Unfortunately, with props, it's not such an exact science as saying a 19" alloy = an 18" SS. Generally it will be close, but prop rake, blade area and shape can all throw that out the window.

There is really only one way to know for certain, and that is to give it a try.

[Harper]

That's your main problem buying something like a prop online. Even if you find a dealer on the web willing to let you try props and return for exchange if necessary (all unlikely), the hassle and shipping expenses will eventually eat up any cost savings. You're better off finding a local dealer who will work with you to find the prop that fits your needs. And with local dealers, that very often includes letting you try different props till you find that right one. And remember, it doesn't have to be an OEM Suzuki prop. Plenty of the aftermarket props are as good or better.

Online purchases will very often get you the best deal, but for some things, it's just not practical.

[2014DF25ARS]

I second that.... I've just bought my third online prop in the process of finding what I wanted. I bought a new Suzuki motor that came with an "11-pitch" aluminum Suzuki prop. I bought a stainless 11-pitch prop online (second-hand, actually a pretty good deal). When I tested the new prop, I found a bigger difference than I expected between two props of the same pitch. (The SS prop allowed me to rev higher and hit the rev limit, where the aluminum factory prop did not. But my max boat speed was the same with both props.) Confused by this result, I went to a local prop guy who measured both props and said the Suzuki prop was actually 12-pitch, though marked as 11. He also gave me cup & rake numbers for both props. So I bought a second SS prop online - this one 12-pitch, and this one gets me where I wanted to be. I'm actually hitting higher RPMs with this 12-pitch prop than with my factury 11-pitch prop. Now I'm looking at probably selling the first SS prop, hopefully at a similar price I paid for it. I feel lucky that the second SS prop worked for me, because I had to pay internet retail for it.

It was very valuable to me to have my prop measured by the local shop. Unfortunately, I have a small 25 HP engine, and my local guy doesn't deal with small props - I think there's just not much profit in it for him. Most of them deal with large-HP fishing boats, etc.

It's also very unfortunate that most prop manufactures don't advertise the technical specs of their props, e.g. rake and cup. There's a lot of hype used in propeller marketing, and this makes it more difficult to predict what you need.