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  1. #1
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    prop slip too high

    What can cause the Prop slip percentage to be too high? Right now I'm sitting around 20%. My prop shaft to pad is about 3.5 in. I'm thinking about going lower. Will that help improve the prop slip?

  2. Member J Risco's Avatar
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    #2
    What boat, motor and prop?
    2021 Phoenix 920 Elite / SHO 250
    Bullet 21XD / 250 XB (Gone to a great home in LA)
    "There is no such thing as a bad day fishing!"

  3. Member J Risco's Avatar
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    #3
    But to answer your question without any info, some possibilities could be:

    Prop needs work
    Motor height wrong
    Weight distribution in boat is bad
    Wrong prop for boat

    Youre thinking is correct though, the cheapest and easiest thing to try (assuming you have a jackplate) is different engine heights to see if any improvements can be made
    2021 Phoenix 920 Elite / SHO 250
    Bullet 21XD / 250 XB (Gone to a great home in LA)
    "There is no such thing as a bad day fishing!"

  4. Moderator 21XDC's Avatar
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    #4
    My first thought is your tach may be reading high.

    Marks Props 317-398-9294, 1850 East 225 South, Shelbyville, Indiana 46176 propellerman59@gmail.com http://www.marksprops.com/index.html

  5. Member J Risco's Avatar
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    #5
    Quote Originally Posted by 21XDC View Post
    My first thought is your tach may be reading high.
    Another very good possibility to add to the potential list haha

    To the OP, thats why Boat/Motor/Prop/gps speed and any other info you can give helps narrow it down.
    2021 Phoenix 920 Elite / SHO 250
    Bullet 21XD / 250 XB (Gone to a great home in LA)
    "There is no such thing as a bad day fishing!"

  6. Member
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    #6
    Quote Originally Posted by J Risco View Post
    What boat, motor and prop?
    2000 21 ss Extreme, 2004 250 evinrude DI, 1.86 gear ratio, 6000 rpm, 62 mph, new 26p razor, 3.5 prop to pad

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    #7
    Sorry I didn't post that info in the original message

  8. Member J Risco's Avatar
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    #8
    Hows your bow lift? Rooster tail higher than motor cowl?

    I would try lowering the engine to 4" under just to see what that does first...
    2021 Phoenix 920 Elite / SHO 250
    Bullet 21XD / 250 XB (Gone to a great home in LA)
    "There is no such thing as a bad day fishing!"

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    #9
    Quote Originally Posted by J Risco View Post
    Hows your bow lift? Rooster tail higher than motor cowl?

    I would try lowering the engine to 4" under just to see what that does first...
    Bow lift is good with this razor 26.

    When I go to full trim, I have a 15ft roostertail, now I drive the boat about 2/3 trim

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    #10
    Quote Originally Posted by leckbass View Post
    Bow lift is good with this razor 26.

    When I go to full trim, I have a 15ft roostertail, now I drive the boat about 2/3 trim
    At 2/3 trim my roostertail is at the height of the cowl

  11. Member J Risco's Avatar
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    #11
    Quote Originally Posted by leckbass View Post
    Bow lift is good with this razor 26.

    When I go to full trim, I have a 15ft roostertail, now I drive the boat about 2/3 trim
    I dont have experience with your exact boat, but all of the Stratos boats I have owned/setup/driven have liked to be run at full trim. This makes me think you need to drop P2P so that you can try running full trim. Just my initial thought and again the cheapest and easiest thing for you to try.
    2021 Phoenix 920 Elite / SHO 250
    Bullet 21XD / 250 XB (Gone to a great home in LA)
    "There is no such thing as a bad day fishing!"

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    #12
    Well, that is the cheapest and easiest thing to try first. I've also been thinking about looking around for a 28-inch raker or raker 2 or razor 28...

    So going back to my original question, will lowering the prop to pad bring down my RPMs a little?

  13. Member J Risco's Avatar
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    #13
    Quote Originally Posted by leckbass View Post
    Well, that is the cheapest and easiest thing to try first. I've also been thinking about looking around for a 28-inch raker or raker 2 or razor 28...

    So going back to my original question, will lowering the prop to pad bring down my RPMs a little?
    Yes, it should
    2021 Phoenix 920 Elite / SHO 250
    Bullet 21XD / 250 XB (Gone to a great home in LA)
    "There is no such thing as a bad day fishing!"

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    #14
    Quote Originally Posted by J Risco View Post
    Yes, it should
    Great, thanks for your help. I lowered the engine one inch. Hopefully test drive tomorrow afternoon

  15. Member lpugh's Avatar
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    #15
    Verify: speed accuracy with cell phone, RPM with digital tach, and actual prop pitch, be sure gear ratio is correct as well. This things must be accurate for accurate results. I would be very suspicious the prop has a problem and may a lower pitch than you think
    Be sure nothing is mounted on the pad area in front of the motor, must at least 18 in off center to avoid water disturbance to the lower
    Thank You Leon Pugh

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    #16
    I'm having slip issues with my new razor 3. Mark sent me a 24 & it was to much & a lot slower then my 24 raker & hole shot wasn't good under a heavy load either. Sent it back & he removed cup & still wouldn't work. Sent it back & he sent me a 23. Hole shot great now, but to much slip on top & throwing a pretty good rooster tail as it has to trim way higher to get any speed out of it. Looks like the front of the cowling is tilted way in towards the back deck if that makes sense. Now it's gone back to add cup for more lift & hopefully increase speed. So back to the old 24 raker lastnight & full of gas, real heavy load & 2 pretty good size fishermen the raker is still by far the fastest prop all the way around except for holeshot. Doesn't really make sense, but i think the raker has been dusted with magic dust or something. I was told i'm running the razor to high & my tach is off, but lastnight the raker was turning 5560 rpm at 66 mph by myself when my buddy went to get the truck.

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    #17
    Quote Originally Posted by leckbass View Post
    2000 21 ss Extreme, 2004 250 evinrude DI, 1.86 gear ratio, 6000 rpm, 62 mph, new 26p razor, 3.5 prop to pad
    I agree with others on checking your tach...

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