Stretch Bike Hauls All

cargobike

Need to haul some stuff? Got nothing to haul it with? Then fashion yourself a cargo bicycle! We’ve seen cargo bikes before, but none quite like this one. Built from a German “klapprad”, [Morgan] and his father fashioned a well constructed cargo bicycle which is sure to come in handy for many years.

They started by cutting the bike in half and welding in a 1 meter long square tubing extension. The klapprad style bicycle is made from thick metal stock, making it sturdy and easy to weld. This process also make it a true “stretch” vehicle as opposed to one that replaces the front end in order to keep the handle bar assembly near the rider.

Along with some nicely done woodwork and carbon fiber, they used parts from an old mountain bike including a front fork, front bearing and handlebar, tubing from an old steel lamp, a kickstand from a postman motorcycle, and a kitchen sink to complete the build. It should handle well so long as the weight of the cargo is not heavier than the weight of the driver.

43 thoughts on “Stretch Bike Hauls All

  1. Unrelated, but why is hackaday.com trying to download flashplayer-pro.exe whenever I goto the homepage?

    also, this:

    Connecting…
    Connection established.

    Confirming input sources…
    Confirming 18.344167 -66.752778… Done.
    Confirming 34.078749 -107.618283… Done.
    Confirming 43.826167 41.586683… Done.
    Confirming 50.524722 6.882778… Done.
    Confirming 52.908889 6.868889… Done.
    Success! All inputs confirmed.

    Acquiring test data… Done.

    Validating test block 1…
    49 27 6d 20 66 6c 6f 61 74 69 6e 67 20 69 6e 20 61
    20 6d 6f 73 74 20 70 65 63 75 6c 69 61 72 20 77 61
    79
    Data for test block 1 is valid.

    Validating test block 2.
    0 0 0 0 0 0 0 1 1 0 1 1 0 1 0 1 1 1 0 0 0 0 0 0 0
    0 1 1 1 1 1 0 1 1 1 0 1 1 0 0 1 0 1 0 1 1 1 1 1 0
    0 1 0 0 0 1 0 1 1 0 0 0 0 1 0 0 1 1 0 1 0 0 0 1 0
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    0 1 1 1 1 1 0 1 1 0 0 1 1 0 0 1 1 1 0 1 1 1 1 1 0
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    1 1 1 1 1 1 1 1 1 0 1 1 0 1 0 0 0 1 1 1 1 1 1 1 1
    0 0 1 1 1 0 0 0 1 0 0 0 1 0 0 1 1 1 1 1 0 0 1 1 1
    0 1 0 0 0 0 1 0 0 1 0 0 0 0 0 0 0 1 1 0 0 0 0 0 1
    0 0 1 0 0 0 0 0 1 0 1 1 1 1 1 0 0 1 0 0 1 0 1 0 0
    1 1 1 1 0 0 1 0 0 1 0 0 0 1 1 1 1 0 1 1 1 0 1 1 0
    1 1 0 1 1 1 0 0 0 0 0 0 1 1 1 1 1 1 0 0 1 1 1 1 0
    0 0 0 1 1 0 1 0 0 0 0 0 0 1 1 0 0 1 1 0 1 1 1 0 1
    0 1 1 0 0 1 0 1 1 0 1 1 1 1 1 0 0 1 1 1 1 0 1 0 0
    0 1 0 1 0 0 1 0 0 0 0 0 1 1 1 1 0 0 1 1 1 1 0 1 0
    0 1 1 0 1 0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 1 0 1 1
    1 1 1 1 1 1 1 1 0 1 1 0 0 1 1 1 0 1 1 1 0 1 0 1 1
    0 0 0 0 0 0 0 1 0 1 0 0 0 1 0 1 0 1 0 1 0 0 1 1 0
    0 1 1 1 1 1 0 1 0 0 1 0 0 1 0 0 0 1 1 1 0 1 1 1 1
    0 1 0 0 0 1 0 1 1 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 1
    0 1 0 0 0 1 0 1 1 0 1 0 1 0 0 1 0 0 0 1 1 0 1 0 0
    0 1 0 0 0 1 0 1 1 1 0 1 1 0 1 1 1 1 1 0 1 1 0 1 0
    0 1 1 1 1 1 0 1 0 1 0 1 1 1 0 1 0 1 0 0 0 1 1 1 0
    0 0 0 0 0 0 0 1 0 0 1 0 0 1 1 1 0 1 0 1 1 0 1 1 0
    Data for test block 2 is valid.

    Configuring reception parameters… Done.

    Begin receiving data? [Y/n] >

    (if this is an April Fools thing, I’m not impressed)

  2. A word of warning for the creator of this unique exhibit, as sooner or later it will break: either at the sprocket attachment point or where handlebar stand and frame meet; the two places where welding has softened the steel. The reinforcements of these ~~shameless copies~~ lookalikes [http://bakfiets.nl/nl/modellen/cargobike/lang/] have a good reason.

    1. Thanks for the warning. In fact it’s the second bike my father made like this. He use the first one since 4-5 years now with a lot of weight in it. The middle bar is thick steel.

      1. When I was a child I had a Klapprad and it broke directly where the hinges were welded on. I think this is the weakes spot in this design, I would control this region regulary.
        Personally I have a Long John, but I think your design is much lighter and has the built yourself bonus :)

        1. In fact the weakest part of the frame is were the tube is bent, near the pedal. The tube is elongated and become thinner. But the Germans did it correctly and the tube is thick, really thick.

          1. But directly at the weld were the hinges were and now is the square tube, there you have a step in steadiness (jump?) which is more likely to break than the continously bent tube.

      2. I’d really like to see more pictures of the build process if that’s the case. Here in Japan these bikes are unheard of, and if you do import one… $$$, I have an electric Klapprad that I’d like to convert to cargo.

        1. Unfortunately I think it’s the only photos we have. But my father would be happy to answer all your questions. If it’s an aluminium bike, I can already answer “No way”.

    2. Almost 10 years later the bike is holding strong! I don’t carry my daughters anymore but a big dog…I use it a lot to move heavy stuff since I’m renovating an house and still no cracks, nothing. My new neighbor made a similar bike and claim to move 90kg. I once move a 1.5 meter concrete post that may weight even more.

  3. What’s exactly so special about a cargo bike? Here in Holland you can see them on a daily basis, they are called “bakfietsen”, or “containerbicycles” in English.

  4. I never understand why everyone goes the hard route and puts the cargo in front. putting it in back is a lot easier as the only thing you need to do is simply put a couple of chains together to make a longer chain and add a single idler wheel. front cargo means a ton of engineering and linkages to make the steering still work.

    1. When extending the bike to have a cargo bay behind the driver, this makes steering more difficult as long vehicles tend to cut corners with their rear wheel(s). It also puts more weight on the front wheel as it will hold at least half of the rider’s weight, the longer, the more, which makes steering a tour de force.

        1. What you saw is the result of a small diameter wheel and very direct steering. I’ve been riding bikes like these for over ten years now and I must say that already after a few kilometers, steering becomes very natural (if you can ride a bicycle already, that is). As for the sturdiness of the steering linkage: the one time a car parked into the bike backward and crushed the front wheel, the linkage was still in tact.

  5. The steering linkage is only on one side, thus it pulls and pushes. One good push and it might buckle. Instant steering realignment! The road or semblance of pushes hardest. The best designs have two links, or one thick one.

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