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  1. #1

    Pump shoe question.

    I have my pump shoe set up to where if a straight edge goes from the hull across both the bolt holes it has a .075 space between the shoe and the straight edge. Its equal on both sides.

    However, I noticed that If I run a long sraight edge down center of the hull and through the middle of the shoe, the shoe actually drops down just below the straight edge (only by a few thousands at the very back of the shoe) but it still drops. I know this isnt the normal place to measure but it just didnt seem right for it to hang low.

    Is that normal or do I have an odd shoe? Keep in mind along the bolt holes I have the proper clearance in front and back.


  2. #2

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    Same with mine.

    I dropped the shoe by .030 and the boat slowed about .5mph, but the boat was more stable or did not seem to want to porpoise (which is what I like) and it seemed to plane faster and recover out of a turn faster.

  3. #3
    Intresting Salty. Is anyone elses like this, Be it on purpose or not?

  4. #4
    Duke's Avatar
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    Not sure what we are talking about here. If I run the level down the middle, the shoe is recessed about 200 thou.
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  5. #5
    Moderator RX951's Avatar
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    My pump shoe is recessed more in the front than the rear. But it does not hang below the hull line.
    * My rideplate angle on both my boats are 1.12. Trim tabs flush to the hull (no washers).

  6. #6
    Duke's Avatar
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    Quote Originally Posted by RX951 View Post
    My pump shoe is recessed more in the front than the rear. But it does not hang below the hull line.
    * My rideplate angle on both my boats are 1.12. Trim tabs flush to the hull (no washers).
    I just measured from the flat surface in front of the pump inlet to get a fixed location to measure the center of the shoe. When measuring the rideplate you must put the straight edge on one contact point on the hull and shoe which is now at an angle making it appear that the shoe is angled. With this position I measure the rideplate. Mine is usually about .950.

  7. #7
    Moderator RX951's Avatar
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    Quote Originally Posted by Duke View Post
    I just measured from the flat surface in front of the pump inlet to get a fixed location to measure the center of the shoe. When measuring the rideplate you must put the straight edge on one contact point on the hull and shoe which is now at an angle making it appear that the shoe is angled. With this position I measure the rideplate. Mine is usually about .950.

    Yup, my level rests on the flat spot on the hull just behind the Keel.

    Measuring my pump shoe with a small straight edge, it is angled slightly from to rear measuring from bolt hole to the hull front and bolt hole to the hull rear. This I am measuring from the side of the hull to the pump shoe. Its typical they sit slightly angled front to rear. Spud had a pic of this I think a while back...I think i have one, I'll have to dig.

    My ski began to porpoise from 960-980, but the higher I went, the porpoise dissapeared. I gained more speed as I got above 985 up to the 1.12. No bounce at all. No washers. Now, I went .010 more to 1.21 and I got a little bounce back. I went back down to 1.12 and that seems to be my sweet spot. Solid and stable.
    I still have not ran the FF plate of my ski yet. Its on my wife's ski.
    Last edited by RX951; 03-31-2007 at 12:07 PM.

  8. #8
    Happily Self-Employed WFO's Avatar
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    Just a side note.

    RX's and Duke's skis do not have the 2 " extension.

  9. #9
    Just to make sure we are all on the same page I will go out and make sure im measuring from the same point as you guys.

  10. #10
    Well I found my problem. It wasnt the shoe that was off, It was the measuring. When I checked it the first time my straight edge wasnt long enough so it was'nt going all the way up onto the flat part behind the keel. I didnt notice while I was under there that the part I was measuring from had already started the upward angle for the intake. With a 4' level it looks good. Its strange how the shoe looks like it drops big time at the rear but the level says different when measuring from right behind the keel.

    Thanks guys.

    BTW on the ride plate Im still finding my sweet spot. It currently sits at 1.09 with the 2" extension. Its fast but gives me a little to much porpoise until max speed. It will probably land somewhere between .940 and .990 W/extension.

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