Wooden Bikes

20090312bike01.jpg Wooden bicycles are always a fun novelty.  I saw what at the time seemed like a very sad image, a child riding on a very crudely constructed wooden scooter. After seeing this video I was happy to see that these sorts of bikes are used as a basic type of transportation for many people in Rawanda. It’s somewhat heartbreaking to see kids in abject poverty with toys like these, but on the flip side, it’s amazing what potential humans have using the tools at their disposal with essentially zero budget.

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These things are pretty neat. You can’t go very fast, but considering what the chinese carry on their bikes these are really a peasant’s truck.You can also race them downhill apparently, but if you live in a third world country, I would imagine this beats the crap out of transporting drinking water from the stream to your village.

Anyways,

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And then you have this group  who is trying to push modern steel bikes on these people. They’re definitely more modern, more efficient bikes, but the difference between the bikes pictured and western style bikes is the fact that their bikes are completely user-serviceable using parts and materials readily available to them. I can only imagine what a chain repair would cost someone – a weeks wages? Replacement intertube, tire? You might be able to fashion some brake pads out of sticks but 99% of the parts on a western style bike are completely irreplacable or unaffordable to the people they’re trying to donate these bikes to.

And then you have this bike, which is a pretty cool, and extremely simple idea. Please excuse the picture of the douchebag in the background, this is the best profile picture I could find of the bike. As you can see it’s three (not two, three) pieces of wood that are all glued together at the headtube, and then joined together with a milled piece of presumably aluminum that acts as a dropout. Probably a decently smooth ride given that you’re essentially riding on two wooden leaf springs. The manufacturer of this bike has used laminated wood (plywood) for the frame, although I suspect you could just as easily use steam bent red oak to accomplish the same thing. If you were going to mass produce these, it wouldn’t be terribly difficult to build a positive mold for the internal shape, and then a negative mold for the external shape, and then litterally just clamp the whole thing together with the headstock and “pedal block” while it cools. Clamping the headtube togther would be a feat, but this bike isn’t out of the reach of the  home fabricator. Here, you can see he’s using a single speed rear cog, but there’s no reason you couldn’t modify the design using a 6″ wide piece of oak and cut it down to size.

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One thing that bothers me is the decision to place the seat tube at that angle. I suppose it gives you the most travel and smoothest ride by putting the seat as near to the top of the arch as possible, but to make the bike last as long as possible the seat tube should mount as close to the droupouts to shift the weight off the “top tube”.Otherwise eventually you’re just asking for structural failure.

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By placing the seat tube near-vertical, you’re taking almost all of the load off the wooden components and placing it on the metal hardware – the seat itself, the seat tube and the dropouts. Not to mention you’re getting rid of a giant hole in the middle of the frame at it’s weakest point. Golf clap for the designer winning an argument with the engineering department on that one.

Fixed:

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One Response to Wooden Bikes

  1. Nick Taylor says:

    Interesting observations.
    The problem was resolved very nicely 70 years ago at the beginning of World War II, by John T. Whalen, with Webster E. Janssen of the Janssen Piano Co., Inc.
    http://amhistory.si.edu/onthemove/collection/object_312.html
    I am a bike maker myself and there are 4 component/frame interface problems which had to be solved.
    Steerer tube/dropouts/bottom bracket/seat tube
    My bikes have been around for 7 years with no failures, they are almost bullet proof :-)
    http://amhistory.si.edu/onthemove/collection/object_312.html

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