SimpleSimon's "Armchair" Tadpole Design

Discussion in 'Motorized Trikes' started by SimpleSimon, Jan 21, 2009.

  1. SimpleSimon

    SimpleSimon Active Member

    Been working on my own interpretation, which I call my "Armchair Truck". It has been fun designing it - seat height is 10" at the leading edge, seat back is intended to be adjustable through a small angle change. Decided, in the interests of having a decent turning radius and still only a 30" wide wheelbase, to use 16" wheels on the front. Since I need centralized steering I went with a tiller raked at 20 degrees, same as the front forks, to a swing arm/tie rod arrangement just under the seat.

    I have some screen captures from the sketching process, with various details still to be filled in, but I'll have to post those later, after trimming/resizing. Modelling that folding top in SketchUp has proven to be beyond my skills - the frame I can do, but the fabric surfaces are much more difficult.
     

  2. srdavo

    srdavo Active Member

    I'm sure eager to see your plans.
     
  3. SimpleSimon

    SimpleSimon Active Member

    Here ya go, srdavo

    As I said, here's my interpretation of the tadpole wagon truck. Coloring of surfaces is just to make it easier too see, and I figured using compression forks for the front suspension would make it ride easier. Still working on it, but as pictured it's intended to be an electric powered town hauler, with plenty of room for motor behind the seat back down low. I've been sketching a lengthened version with more room behind the seat for a gas engine, as well, but jawnn distracted me with his post - that and other comments I've read regarding figuring out how to mount an engine on a fully recumbent tadpole and still have room for cargo, and I've been working on a short wheel base one with a flatbed cargo area above the rear wheel.

    With trikes, steering geometry is critical too handling, as everybody knows. Steering rake is a function of wheelbase width/length issues - to keep the width in the neighborhood of thirty inches (getting it through doors, fitting on bike lanes, etc) means that the longer the wheelbase, the more upright steering angle needs to be. Twenty degrees is about as much rake as one can reasonably aim for, as that gives a wheelbase length right at three feet with a 30 inch width. As pictured here, rake is 19.9 degrees.
     

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  4. srdavo

    srdavo Active Member

    thats pretty cool. thanks. I like it.
     
    Last edited: Jan 22, 2009