17 thoughts on “Super stable motorized kayak project, by Kenny “One-Shot” Tracy”

  1. Thanks Kenny,


    Calling this a kayak would be a little misplaced, but it looks like a great boat! πŸ™‚
    The foam block at the rear end of the saddle might cause some drag if it comes in contact with water at high speed.
    Otherwise, this thing looks super stable.
    Testing it would tell you if you can load it above the 360 lbs limit we set.


  2. Thanks Yoav!


  3. One-Shot,

    You may want to consider adding two crossbars (see below image) that would prevent to side floatation from getting pushed upward by the weight of the boat and its payload. Think ‘catamaran’…



  4. One-shot,
    Great job! The seat looks very cozy but I wonder would it allow you to steer comfortably with a tiller, and would it allow access to the controls on the motor?

  5. This boat is getting more interesting every day!
    I’d still try to move the transom mount forward, closer to the driver, and I’d also move the seat forward too so the tiller extension with the U joint gets more wiggle room.

  6. Whoo Hooo Yoav! Outstanding suggestion! Perhaps I could fabricate some crossbars from some aluminum crutches (eBay) so I could keep it strong, rigid, and lightweight. Actually, that was the major reason that I didn’t make them level with the bottom of the hulls/pontoons. Since the draft averages around 6 inches, I mounted the foam 6 inches above them to minimize the upward push. This modification will be similar to the way race car frames are reinforced! You are truly a genius! Thanks!

    The seat IS quite comfortable. It’s actually a “center” seat for a bass boat. If it were about an inch lower, it would be ideal! The last time I went out, I scooted forward and rested my head on it, and took a little nap, a little longer than I had planned… But that’s another story in itself! LOL.

    I made a tiller arm extension out of some PVC pipe/fittings, a rubber sleeve, and hose clamps. With my trolling motor mounted in the rear, sitting in my seat, scooted up towards the middle of the saddle, and occasionally standing, I managed to control it fairly well after I got the hang of it. It shouldn’t be too awkward of a reach to start it up. A friend of mines utilized some PVC to fabricate a remote gearshift lever on his Jon/crab boat. I plan on utilizing some parts from a “donor” motorcycle I just happen to have too… Send me some of you suggestions. I can use all of the help I can get from my new “family”!


  7. One-Shot,

    Maybe the next thing to do is dry-test this boat with the outboard motor on, and see how it feels to steer, start the motor, lift it and lower it, I.E. operate it.
    If you still didn’t choose a motor, I’d recommend you get one with a long (20″) propeller shaft. It would enable you to attach it closer the cockpit, and therefore closer to you, for more convenience.

    As for the crossbars, aluminum sounds good, and I’m thinking that even plywood would do.
    The problem is that the way these foam blocks are attached now, they will start moving up and down, eventually, and that would loosen the bolts’ grip and/or could even cause the foam to break.


  8. Great idea Pete!

    It gets a lot of attention wherever I/we go! I have a fish finder, but I’d like to upgrade to one with a GPS on it next. I also have a “trick” dolly system for the front that I need to re-install. I am truly enjoying myself making it fit ME, and sincerely appreciate all of the many hints and suggestions that my new “Fam” offers.


  9. Yoav,

    My plan was to remove my foam after it’s final shaping, and reinforce the mounting points with epoxy resin infused carbon fiber strips. Another person familiar with fiberglassing suggested that I just “paint” the rest of the exposed foam and wood with just the resin to protect/preserve it.

    I made my mount for a 20 inch propeller shaft, but I haven’t purchased it yet. The major reason I want a 6 hp motor is not for the speed, but because it’s the smallest motor that I’ve seen that has a reasonably priced alternator option for it. I’m open to a smaller/lighter motor with an alternator, if I can get it for under $1,700.00.

    The reason why I’m so hard-pressed to keep that foam in front of my transom mount is because I’ve noticed how low the rear of the boat gets when under acceleration, and it’s ability to allow me to climb into my boat from the rear without me swamping it. The foam also makes it easier for me to level my boat out without having to be positioned more to the center of the saddle. These are my “seat-of-the-pants” observations, and I have no hydrodynamic evidence or facts to prove my theory, but because it’s worked for me, I’m going to stick with it. I believe that now, when the speed of the W500 gets around 9 or 10 mph, and the boat wants to “wander” uncontrollably, it’s because the rear gets low and wide and sort of splays outward, while the front end gets narrow and is is pulled up too high to keep a consistent grip on the surface of the water.

    Thanks again,

  10. Kenny,

    Try using this epoxy solution on a piece of Styrofoam before you apply it on the boat itself. Styrofoam is very sensitive to solvents, which makes its surface dissolve, and all strong adhesives contain strong solvents. Also, priming and sanding is a lot of work πŸ˜‰
    When I experimented with Styrofoam I switched to latex because of this. It’s water based, and another advantage of it that you don’t have to sand it.

    There are two ways to counter affect the rise of the bow and the sinking of the stern – One is by trimming the propeller shaft, and the other is by having the driver operate the boat from the middle of the cockpit using a long jointed tiller extension, instead of sitting at the stern.
    If you use one method and not the other it won’t be enough, especially at high speeds such as a powerful motor can deliver.
    With the stern sitting low, that piece of Styrofoam at the rear end of the saddle would be subject to high pressure (with several hp pushing against it…), and it could very well get ripped away after causing all sorts of hydrodynamic issues (translation: drag, turbulence) that might impede the boat and/or create steering and/or tracking issues.


  11. Thanks again Yoav!

    I regret not logging in immediately after I first purchased my “baby”, although I had several conversations up to, and shortly afterwards with my salesman from the Richmond area.

    My styrofoam is actually extruded polystyrene, and was sold in billets. It is most commonly used in building construction and building floating boat docks. Each 4 foot billet can float 220 pounds. I ordered two 4 foot billets initially, and then two more 8 foot billets (440 pounds of floatation each). Theoretically, AFTER shaping, fitting, and sanding, I have the ability to float an additional 1000 lbs of weight from my kayak! No, I will NEVER attempt to prove this theory, but it is reassuring to know this, when you are offshore 5 or 10 miles. I haven’t weighed it, but it doesn’t feel like I’ve added more than 35 more pounds to my structure (including the wooden mounts and hardwire). I’m going to find a way to integrate the foam more seamlessly to the rear, so the drag will be minimalized.

    Polyester resin will melt/dissolve my foam, but epoxy resin works very well with it.

    I’ve already purchased a quantity of “pourable foam”, and with the kayak turned over, I’d like to pour enough to just cover the reinforcing brackets in the saddle, and “bridge” the bow and stern. If I make the last 6-12 inches of the underside of the stern almost equal to the depth of the hulls, I’m fairly confident that the “drop” from the increased weight of the motor will be minimalized. I am going to install a hydrofoil to my outboard too, to further trim it while underway.

    By the time I’m finished with this project, my “W” is going to think she was born this way! LOL

    Thanks for being a blessing,

  12. Kenny,

    This is a very special and exciting project by any standard. You’re definitely pushing the envelope here πŸ™‚
    Pouring urethane foam under the saddle sounds like a good idea, but you’d need to find a way to make it stay there, because if you don’t it will ‘escape’ as soon as it gets a chance..
    I’m not sure what you want to achieve with that hydrofoil – Why not wait until you got the other pieces in place?

    Most important: Let’s not forget a saddle bracket. This boat would definitely need such a structural element to help it maintain its form, at least as far as the initial W500 is concerned πŸ˜‰


  13. Hi Kenny-

    If you want to use a casting of foam under the saddle you might consider embedding some small rings (with big feet). You could run bungees through them to hold the casting tight to the “ceiling” as we do with the standard floatation tubes.

    On the other hand, if you add much more foam to this project you may be required to obtain a dirigible license! πŸ™‚


  14. Thanks Michael,
    That’s an excellent idea! But, did you just call my beloved kayak a blimp?!? πŸ™‚ . I promise it will be more streamlined when I finish! πŸ™‚

    I appreciate ya,

  15. Streamlined or not… as long as it flies! πŸ™‚

  16. Yoav,

    I will definitely be ordering a saddle bracket or making one, soon. I’m getting a garage within the next month or so, so hopefully then, I will really get some things done!


  17. Wow, I can’t wait to see it after you work out all the bugs.

    Good luck, and I will wait for more updates. πŸ™‚

    Tight lines and MoPaddle Safe all.

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