Electric Tadpole Recumbent Project

Discussion in 'General Questions' started by maxwell65, Mar 6, 2009.

  1. maxwell65

    maxwell65 New Member

    Hi everybody,
    I am interested in creating a 48v50ah tadpole recumbent; such a bike would provide speeds up to 40mph and range of apx 40 to 50 miles. Total cost for such a bike, including frame, motor, and lifpo4 batteries and other bike parts will be in the neighborhood of $1500.00 to $2000.00 NOT including labor.

    I will embark on creating one if I can get a few people interested in having one for themselves, I of course will pay for mine, this is a non profit proposition, I have experience in building electric bikes, and I get all the parts (motors, controllers, lithium batteries(lifpo4) etc) at wholesale prices as for the framing of the bike I can get all the materials new at wholesale as well, ideally a design would be created in CAD, I have pics of an electrified tadpole which would be similar to the one we would design with a few differences that will provide for "cleaner lines",using a crystalyte 5303 hub motor as opposed to an "external" motor, hopefully there is someone who reads this that has the capacity to work in CAD, possibly using a program called Solidworks, if so and you wish to participate in this let me know, payments can be arranged for this service if need be.

    Once design is made all tubing will be cut and soldered at a very cost effective manner, thanks in part to the fact that my step dad is a professional welder whose vast experience in aviation industry will be put to good use, he has the time to devote to this project as he is now retired and is excited to have one of these bikes for himself.

    As for me I am a builder who's proficient in plumbing, electrical, so if we start welding these frames I will learn from the pro himself.

    So if you are willing to add your experience to this project, great! If you have nothing to contribute yet you would like to have one made for you at a rock bottom price, then contact me for arrangements. The bottom line is the more people that want this bike the easier and cheaper it will be to produce.

    Max Kogan

    Attached Files:

    Last edited by a moderator: Dec 15, 2015

  2. SimpleSimon

    SimpleSimon Active Member

    Interesting proposition.

    I've been designing bikes, mostly tadpole recumbents, for a fair while now. I don't have a CAD program, so I do my designs in Google SketchUp - there are few posted here on the board. I have one delta trike specifically designed for electric assist - designed around the NuVinci CVT hub as a mid-drive that receives input power from both the pedals and the electric motor, then uses ring gears mounted at the spoke flanges to drive two seperate jackshaft half axles.

    The half axles are concentric with the axis of pivot for a single swing arm rear suspension system, with final drive loops of fixed length from the axle shaft to the jackshafts. With a freewheel on each wheel, the combination acts as a poor mans differential - the outboard wheel in a turn is free to turn faster than the drive speed. You end up with fully independent rear swing arm suspension, and power to both wheels. As I have designed it, it would have 26" rear wheels, and a 16" front raked 45 degrees. About all I need do to finish that design is add the details such as pedals, handlebars, wheels.

    I've also done some design work for a similar full suspension tadpole.

    In most of my designs, I aim at a seat height below the CoG of the bike - usually in the neighborhood of 10-12" above ground. Some vary from that. See:
    Armchair Truck
    Last edited: Mar 6, 2009
  3. maxwell65

    maxwell65 New Member

    hi simon

    hmm i'll have to check out SketchUp,i've included a pic of more or less what i have in mind,i feel its a great design in the sense there is a good amount of space to place the batteries and because it has pedals it is more or less street legal.i checked out both your designs and the radical looks great and the other one i guess is for cargo.