• Hildegarde@lemmy.world
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    5 months ago

    Imagine designing a bicycle without triangles. Every joint needs to be overbuilt, because there’s no structure from the geometry. But you make sure it still has a top tube, so its just as hard to mount and dismount as a normal bike. Incredible!

    • Kecessa@sh.itjust.works
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      5 months ago

      Right? Who would be crazy enough to do that?

      Next you’re going to tell me someone will make one without a top tube?

      • dejected_warp_core@lemmy.world
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        5 months ago

        Hey, look here buddy. You can’t be your own comment thread and post all the plausible responses yourself like that. You’re putting all the trolls out of work.

      • pyre@lemmy.world
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        5 months ago

        doesn’t that prove their point? they all look overbuilt, as the original commenter said.

        • Kecessa@sh.itjust.works
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          5 months ago

          Carbon fiber, aerodynamics…

          For this one it’s used as suspension (not carbon fiber)

          Not that rare in old mountain bikes either, pretty sure my old steel Raleigh was similar

          • Natanael@slrpnk.net
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            5 months ago

            Carbon fiber has very limited lifetimes when used for something with a lot of hard impacts, so if you’re not sticking to smooth surfaces the bike can literally split apart with little warning

              • Natanael@slrpnk.net
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                5 months ago

                I Googled “motorcycle carbon fiber wheel” and autocomplete immediately suggested adding “failure” and doing that search has endless relevant results

                • Kecessa@sh.itjust.works
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                  5 months ago

                  And if I do a research for “Toyota Tercel engine failure” I find tons of results as well even though it’s one of the most reliable car ever built.

                  Crazy how search engines show you results for what you’re looking for, right?

                  • Natanael@slrpnk.net
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                    5 months ago

                    https://www.bikeradar.com/features/are-carbon-fiber-clinchers-safe

                    They have limited tolerance for heat that you can’t solve without either improving cooling or reducing hard acceleration / deceleration (using additional material) when used in wheels. When used in frames you need to reduce stress points with very good dampening.

                    They can certainly be strong, but they have similarities to tempered glass where damage accumulates over time and can’t self heal so they have a best before date built in.

      • Hildegarde@lemmy.world
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        5 months ago

        The meme shows only bikes with flat handlebars, like commuter bikes intended for transportation.

        Every bike you posted are high performance racing bikes with specialized aerodynamic handlebars.

        Different priorities. Triangless bikes with a top bar is not a good idea for commuter bicicles like the ones in the meme.

        • Kecessa@sh.itjust.works
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          5 months ago

          I still showed that it’s perfectly possible to build a bike without a seat tube, hell I’m sure we can find 90s examples that weren’t high performance bikes.

      • bcron@lemmy.world
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        5 months ago

        Compliance but this is a very very extreme example - you’d hit a bump and the top tube would flex, kinda like a diving board, and smooth out the harshness. I’m not even sure this bike exists but that would be the practical purpose of such a design, but most manufacturers tend to go after the seat stays (Salsa Warbird, Bianchi with Counterveil, Moots Routt YBB) or decouple the seat tube from the top tube and allow it to flex due to seat tube angle (Trek Isospeed). Carbon’s kinda fickle and engineers are constantly trying to figure out how to finesse it into feeling less jarring and rigid

        • Wogi@lemmy.world
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          5 months ago

          This bike does not exist. This is part of a series of theoretical renders from what must be 15 to 20 years ago. When carbon fiber was kind of a new material to the general consumer. The premise was they could not only reduce the weight of the material but because carbon fiber was this space age super material that could melt your tits off if you looked at it sideways, that they could also reduce the need for structural materials like spokes and triangles. Making a featherweight racing bike. Most of the designs had absolutely no way to steer them.

          • bcron@lemmy.world
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            5 months ago

            I was gonna say, the frame just looks a little too outlandish, totally ignoring the wheels and headset.

            Once in a while a bike comes along trying to reinvent the triangle but none are particularly good, often worse than tried and true. Superstrata Classic is a perfect example. Making a 2 triangle frame and adding just a hair of compliance around less-critical spots seems to be the winning formula

      • uis@lemm.ee
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        5 months ago

        At compressing part of bend. If I remember correctly, carbon fibers are good at handling tensile loads and terrible at compression loads.

    • XEAL@lemm.ee
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      5 months ago

      Nah, but that tube is a little lowered, enough to make a difference.