Orbea GROW and a few midweek links

Orbea GROW kids bikeThe idea of creating bikes that grow with kids that has been around, but designer Alex Fernandez Camps’ approach for Orbea is interesting. Many kids bikes allow for substantial adjustment of seat and stem height, but Camps’ design features an aluminum frame that can be expanded horizontally as the child grows. The GROW bikes come in 3 sizes for different age ranges. Read more, and check out a video on Treehugger.

GrabCAD, a mechanical engineering community with 90,000 members, has been organizing a few bike related design contests lately. The crank weight reduction contest for Tern has already ended, but there are still a few days left to get in on the contest to “improve the finishing details to hold the handle bar tape in place.”

ROTA folding bicycle conceptThe ROTA Bike, by Leandro Albino Oliveira, is another rendered folding bike concept posted at Yanko Design. The last image in the post briefly explains the pivot mechanism, but there is not much detailed information in the post.

Jewelry designer Jeni Oye uses old bike tires to make cuff bracelets for men and women. They look nice, but most of the tires in the images don’t look very used to me. When I remove a tire from one of my bikes…there is definitely no mistaking it for a new one.

SRAM Red hydraulic rim brakeFinally, I’ll mention this Road.cc post with “spy shots” of future SRAM Red hydraulic disk and rim brakes. Interesting! Look for more info about SRAM Red here at Bicycle Design later in the week.


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8 responses to “Orbea GROW and a few midweek links”

  1. WV Cycling Avatar

    I really wish the bottom bracket height on the orbea kids bikes raised and lowered also. Pivoting the chain/seat stays in a semi-permanent way would be ideal. This way, the bike would truly grow with the kids.

    1. art Avatar
      art

      Optimal bottom bracket height is the lowest you can get away with for the crank arm length. There’s no reason to have it go up for a taller rider.

    2. kfg. Avatar
      kfg.

      For all the work they still end up needing 3 frame sizes to go from first two wheeler to adult, just like the traditional way of handling the issue. Wheel, crank length, bottom bracket hight, etc all need changing to maintain proper proportion with the different sizes of the rider.

      And guess what happens when you raise the seat on a traditional three frame sizes bike?
      The virtual top tube gets longer because the seat post is set at an angle. But people at the trade show don’t go “Ooooooooooo!” when you raise a seat and put on a stem with an inch more extension.

  2. Mike Avatar
    Mike

    The Orbea is a solid idea, and fairly simple. The ROTA, however, checks all of the classic CAD trash boxes — no seat stays, single chainstay with drive on the opposite side, physically impossible front wheel paired with a radially spoked rear, and a complicated new mechanical element that the person is unqualified to design. Not surprisingly, the designer is someone who has never brought a product to market; his whole portfolio is graphic design, renderings, and packaging.

    1. Androo Avatar
      Androo

      Eh? Seatstays aren’t necessary when you aren’t using tubular construction, the chainstay is in between the wheel and the drive sprocket, the lacing pattern of an off-the-shelf component is irrelevant, and that folding mechanism is about as simple as it could possibly be.

      Basically, the dude designed Mike Burrow’s 2D folder with a different hinge point:
      http://www.foldsoc.co.uk/IMG_0412a.jpg

      You can say it’s derivative, but to say it’s impossible CAD trash is just being close-minded and curmudgeonly.

      1. Mike Avatar
        Mike

        You are correct that the chainstay is between the drive and the wheel, it looked otherwise to me when I first looked at it. As I think we sussed out on here last time someone had a one chainstay design, this isn’t really physically possible without a huge S bend in the chainstay like a Giant Halfway (a Mike Burrow design IIRC). The Halfway has a seatstay, of course; not familiar with the one you posted the pic of but I’m willing to believe that someone like Burrow could make it work. Anyway, in carbon I would think it would be either very weak or very heavy, and the Q factor and heel clearance might still be unacceptable.

        We might have had some insight into those issues if the “designer” had built a prototype instead of a series of renderings. Of course, then it wouldn’t be on Yanko, because then it wouldn’t be vapor, and if a mechanical object that wasn’t vapor were ever posted on Yanko the universe would surely explode. I’ve said if here before: Yanko is a marketing channel, and the things you see on there are made by people who market for a living, not design for a living.

        I point out the spoke lacing because as usual with CAD trash the wheels aren’t drawn correctly because drawing wheels on a computer is hard. Of course, if you drew one you could reuse it, but none of the people generating this junk ever do multiple bike projects so why bother? This particular variant shows more ignorance of how a wheel works (and the laws of physics) than usual, which makes it noteworthy, if unsurprising given that the designer has a background in things like graphic design and packaging.

        I may be crumudgeonly, but I’m just tired of seeing stuff like this win student design awards (which it did — came in 3rd in some Brazilian competition) when what the student really needed was to be told to put down the mouse and pick up some tools. Presumably if you read this blog you do some kind of design work, so ask yourself this: would you be more likely to hire this person to design mechanical objects if they came to you with these drawings, or with one sketch of the overall design and a working model of the hinge element he came up with that is the key piece and only original part of the whole thing?

      2. kfg. Avatar
        kfg.

        “Seatstays aren’t necessary when you aren’t using tubular construction”

        And leaving them off makes sure people don’t mess up their bikes with useless crap like fenders, racks, lights and other such garbage that makes them look less like an Über Kewl BMX bike than something really useful.

  3. art Avatar
    art

    That’s a nice looking caliper, but I’ll really be impressed if there’s a road lever to go with it.

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