In an effort to combat high production costs, Korean designer Jaemin Lee proposed an alternate frame solution by taking the more simple front triangle of a standard bike and replacing it with an injection molded element. Using a simple rear triangle that could be just snapped into a two piece front, the design allows for a degree of modularity that would still allow frame size and even gearing flexibility in an overall bike that should be able to dramatically lower costs for a city riding bike. Take a closer look after the break…

Placha_plastic-bicycle_Jaemin-Jaeminlee_3 Placha_plastic-bicycle_Jaemin-Jaeminlee_2

The main frame would be injection molded plastic injection in two parts with internal ribs for reinforcement that would give rigidity and keep a low weight. While molds would be a relatively expensive startup cost, even molding with a reinforced engineered plastic, each mainframe would be very cheap to produce in large numbers, with molded-in colors cheap and easy. The two halves would just snap together with collars at the headtube, seattube clamp, and bottom bracket further locking it all together.


Placha_plastic-bicycle_Jaemin-Jaeminlee_4 Placha_plastic-bicycle_Jaemin-Jaeminlee_5

Outside of the plastic (and recyclable) mainframe and the most-likely aluminum rear end, the bike would use standard components throughout allowing for low budget commuter bikes or individual customization.  A pair of holes in front of the headtube are designed to support a modular carrier that would snap in in the same way as the rear triangle. A simple porteur-style rack is the most logical solution, but the designer suggests that other items like a handlebar bag or even lights could be mounted as well. The frame also includes a special water bottle holder, which would use a specific bottle that is held in-place by retractable pins inside the plastic frame.


  1. This has some good thought behind it – looks more robust than the Swedish Itera from the 80s and some other concepts that’ve trickled out in the last 10 years. If you’re gonna concept a plastic frame though, do the rear triangle as well. The biggest failure point might very well be the 2 junctions of different materials, and you’re washing most of your production savings by still having welds at the dropouts (plus the assembly time of putting together the F and R triangle). And at the very least, design some matching wheels to really exploit the mass-production benefit of IM plastic. Wheels have been done successfully, not simply vaporware.

  2. No brakes and the rear end doesn’t look sturdy enough for skid-stopping. Lame.
    Injection molded plastic bikes have been done before. And there’s a reason why they are gone.
    When you factor in reliability, the production cost ends up higher than convensional methods.

  3. no way would this save money over current manufacturing. It’s actually quite cheap to build a simply double diamond cromo frame. This is simply a design exercise. not a scalable design

  4. So…I’m assuming one would recycle the plastic mainframe after each week’s use?

    Brilliant, really. Gillette and Schick have had disposable razors for years. Until Dollar Shave Club beat them at their own game.

    Imagine: a weekly subscription where they would send you a new frame every week, and you just recycle your old one. Durability issues solved! And you could fashionably change colors to whatever suited the current hipster trend.

    I sense a successful KickStarter in the works, people…

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