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Thread: what pitch prop do you run on your 50hp?

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    Member rrjfish8's Avatar
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    Default what pitch prop do you run on your 50hp?

    I have a 50 honda on a 18'8" harbercraft and run a 13 pitch prop. Just wanted to know what other people run on their 50 and what boat. I am thinking of getting a 15 pitch SS prop for just a little more speed when running in the bays.

  2. #2

    Default One size fits All

    Depends if you run you boat with heavy load or for max speed or all the combo there of. ?


    129CReplacement Blade: 12-1/4 x 9, C-Style12-1/4 x 9 x 3(19 - 22) MPH1211CReplacement Blade: 12 x 11, C-Style12 x 11 x 3(23 - 27) MPH103/813CReplacement Blade: 10-3/8 x 13, C-Style10-3/8 x 13 x 3(28 - 32) MPH111/213CReplacement Blade: 11-1/2 x 13, C-Style11-1/2 x 13 x 3(28 - 32) MPH101/815CReplacement Blade: 10-1/8 x 15, C-Style10-1/8 x 15 x 3(32 - 37) MPH121/415CReplacement Blade: 12-1/4 x 15, C-Style12-1/4 x 15 x 3(32 - 37) MPH113/417CReplacement Blade: 11-3/4 x 17, C-Style11-3/4 x 17 x 3(36 - 42) MPH

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    Default Is there a good pitch to use for heavy loads?

    My boat only runs about 25-28 mph on step with two people and little gear. With 4 people and little gear I go down to 15. Would changing props help? Also getting on step with four people and coolers would be a nice change! Any Ideas????
    I run a 50 hp honda four and a 18' Alumaweld stryker dry weight 880lbs.
    Good judgment comes from experience, and a lot of that comes from bad judgment.

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    Default

    To determine the proper pitch it would be helpful to know what your maximum rpms are at WOT. I suspect that the the factory recommendation is in the 5K-6K range. I like to see between 5500-6K personally. With boats this size, hydrofoil planing fins such as the doelfin can really help getting an underpowered boat on step. I had one on an 18"klamath with a 70 horse evinrude. It really helped performance. Very little bow rise and porpoising was a thing of the past.
    Spending my kids' inheritance with them, one adventure at a time.

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    Default 5500-6000 Rpm

    I have a fin on my out board. I would really like to get a 75-90 hp motor but just can't afford a 9k dollar motor right now. The only problem is you can't run it in the Kenai if I move up to a 75-90.
    Good judgment comes from experience, and a lot of that comes from bad judgment.

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    Quote Originally Posted by motorboatn View Post
    I have a fin on my out board. I would really like to get a 75-90 hp motor but just can't afford a 9k dollar motor right now. The only problem is you can't run it in the Kenai if I move up to a 75-90.
    If you are turning 55-6000 you are propped right, IMO. I assume that this is with a lighter load and your 15 mph speed is with a full boat. Can I also assume that you are not turning max rpms with the heavy load? Rule of thumb is each inch of pitch will change your rpm by 100. You could try dropping down a couple of inches in pitch with a heavily loaded boat. This might get you the speed you are looking for. An extra 40 horses will do this, too.
    Spending my kids' inheritance with them, one adventure at a time.

  7. #7

    Default Well now

    Yes changing pitch when you change weight will change your preformance it's one reason I started using the composite props. Plus when you hit some thing hard it flexs so's not to break the shaft. I do loose being that the prop flex's, but for the price of one SS prop I can have 4 different pitches. And they take a hit and no bent or broken prop blades.
    Folks out in the villages like them because they go to town empty and come back full changing the pitch is easy.

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    Quote Originally Posted by alaskapiranha View Post
    Yes changing pitch when you change weight will change your preformance it's one reason I started using the composite props. Plus when you hit some thing hard it flexs so's not to break the shaft. I do loose being that the prop flex's, but for the price of one SS prop I can have 4 different pitches. And they take a hit and no bent or broken prop blades.
    Folks out in the villages like them because they go to town empty and come back full changing the pitch is easy.

    That system looks to be a great setup for running the rivers. Very reasonable, too. I noticed that yamahas are not listed there. What is up with that?
    Spending my kids' inheritance with them, one adventure at a time.

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    Member rrjfish8's Avatar
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    Default RPM

    The rpms will hit alittle over 6000 and i turn it down because i know it is too much. I cruse at 52-5400 with 27mph. With the rpms going over 6000 i think i could improve proformance by a larger pitch. Am i right?

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    Quote Originally Posted by rrjfish8 View Post
    The rpms will hit alittle over 6000 and i turn it down because i know it is too much. I cruse at 52-5400 with 27mph. With the rpms going over 6000 i think i could improve proformance by a larger pitch. Am i right?
    Sounds right to me. You will lose some hole shot with the increase in pitch, but your top end should improve as well as your cruise.
    Spending my kids' inheritance with them, one adventure at a time.

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