Built by a 56-year-old Italian mechanic for his daughter, Erika, after she broke her arm practicing. [via Dude Craft]


Sean Michael Ragan

Sean Michael Ragan

I am descended from 5,000 generations of tool-using primates. Also, I went to college and stuff. I am a long-time contributor to MAKE magazine and makezine.com. My work has also appeared in ReadyMade, c’t – Magazin für Computertechnik, and The Wall Street Journal.

  • Mark Williamson

    Gearing unicycles (“gunis”) is more highly developed than one would expect – the relatively niche market of distance unicyclists is still large enough (and, seemingly, containing enough technically-minded people) to support some interesting solutions.

    Schlumpf now make an epicyclic unicycle hub: http://www.schlumpf.ch/hp/uni/uni_engl.htm
    these are a reasonably natural evolution, given Schlumpf’s previous work on epicyclic gears for bicycle bottom brackets: http://www.schlumpf.ch/hp/schlumpf/antriebe_engl.htm

    Unlike Greg Harper’s creation (which was ahead of it’s time), the Schlumpf is on-the-fly shiftable using buttons that are fitted in line with the wheel’s axle – it’s possible to shift by tapping a button with your foot. Many top distance unicyclists have used these since they became available.

    There’s also an extra-strong version of the Schlumpf hub for offroad unicycling: http://www.krisholm.com/khu/kh-schlumpf

    Pete Peron’s Purple Phaze:
    and Red Menance:

    (amongst others) use an alternate gearing system based around a “jackshaft”, which is quite interesting. I think this arrangement (or similar) has also been seen on some old-fashioned bicycles but it’s basically never seen these days. The jackshaft-based gunis are not on-the-fly shiftable but can be geared up to insane ratios.

    It’s pretty cool stuff anyhow; Grep Harper’s hub (as linked) is the first epicyclic uni hub I’m aware of existing and predates the Schlumpf by quite some time.

  • nick

    The training wheels are kind of a neat idea, but with that little ground clearance I’m not sure how you’ll learn to balance.

    I think it would work better if it went vertical as close as possible to the wheel, and leave enough ground clearance to ride fairly normally, so the rider still has to balance and the wheels are only there to give a chance to recover when they get too far out of balance.

    Afterall, if you’re going to rely on a 2nd wheel to keep you upright, it’s called a bike. ;)