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> (Some commenters have suggested that it was not obvious that a two-wheeled vehicle would balance, but I find this unconvincing given how many other things peo

> (Some commenters have suggested that it was not obvious that a two-wheeled vehicle would balance, but I find this unconvincing given how many other things people have learned to balance on, from dugout canoes to horses themselves.) I'll be one of those commenters I guess.... What!?? Balancing in a canoe is in no way similar to a bicycle. I can jump in a canoe having never been in one, and it will balance itself. I can probably even manage a few trepidous rows of an oar (or hand, or arbitrary object) without tipping it. Without me, the canoe will stand on its own. If I fall, it will often right itself without me. On top of that, a canoe is both an evolution on previous working designs (rafts), and analogous to nature (whether it be a fish, crocodile or a floating log). The horse, with its four (not two!) legs is an even more ridiculous comparison. It seems pretty clear that the development of the bicycle would've been significantly hampered by the fact that balancing on two wheels was: (a) unintuitive as an idea with no analogue in nature or previous innovations (b) had a marked learning curve (c) that learning curve was separate and independent for each design. Riding a modern bicycle doesn't automatically make you an adept penny farthing, unicycle, nor tandem rider. Nor any of the umpteen other technological iterations. I wouldn't be surprised if this trumped material/manufacturing limitations as a hurdle. See this whimsical video for "evidence" of this [0] [0] https://www.youtube.com/watch?v=0yJdz-kjfLk https://www.youtube.com/watch?v=0yJdz-kjfLk

tcmb 7y ago
If you saw off a disc-shaped slice from a log of wood, and it rolls a few meters, you experience first hand that a single wheel can balance itself. Some say this is how the wheel was invented in the first place [citation needed].
- SiempreViernes 7y ago
  Right, now stand on said disk. Turns out the you+disk system doesn’t trivially balance...
  - tcmb 7y ago
    That's not a fair continuation of the thought, is it? Even balancing on an entire rotating log isn't trivial. The problem here is standing on a small patch of surface that is moving under you. The required insight for the bicycle is that, counterintuitively, a rolling wheel doesn't fall to either side. The axles, fork, frame, and seat are 'just' the elaborate way of mounting yourself to those rotating discs so that you can move along with them while sitting still.
- woodandsteel 7y ago
  That sounds like a unicycle, which is a hundred times harder to balance than a bicycle. The physics of how a bicycle balances itself when you are moving is very different than that, complicated, and quite unintuitive. Basically when the bike starts to lean to one side, the rotation of the front wheel causes it to steer to move the bike underneath the direction you are leaning. This happens several times a second, and faster than a human can react. https://www.citylab.com/design/2015/05/the-weird-wonderful-science-of-how-bicycles-balance-themselves/392690/ https://www.citylab.com/design/2015/05/the-weird-wonderful-s...
  - lovemenot 7y ago
    >> ... a unicycle, which is a hundred times harder to balance than a bicycle. It's not that hard to unicycle. It just seems so to people who didn't try it until they were an adult. In Japan, any junior high school may have a few unicycles and you frequently see kids larking around on them in the playground. Nothing special.
    - wingerlang 7y ago
      Agreed, i think they take a somewhat equal amount of time to get going on. Probably takes a few hours over a few days on both of them to get going.
  - jhrmnn 7y ago
    Anyone can experience this by overtightening the headset (the steering axis) on a bike. Suddenly one has to focus on balancing way more and riding a bike no handed becomes almost impossible.
deathanatos 7y ago
> The horse, with its four (not two!) legs is an even more ridiculous comparison. The comparison is, as I understood it, the rider balancing on the horse itself. I've only ever done this myself with saddle and stirrups, so I don't know if this is significantly more difficult without those. I think you're being a little generous with the canoe. Boarding a canoe without a dock (that is, climbing in from the water) is tricky, and requires some thought about where your weight is. (Since the lip of the canoe, in my experience, sits well above the water line, and you're about to pull down on the edge to attempt to board, but that same motion is the motion that moves the edge closer to the water which will flood it.) I've seen plenty of people flip and subsequently flood a canoe after an unsuccessful attempt to board.
- JackFr 7y ago
  But a canoe floats, as a horse stands. A bicycle simply does not stand up on its own.
  - pbhjpbhj 7y ago
    Surely it can, it's just a case of finding the balance point? [Ignoring macroscopic effects of the Earth rotating, etc.]
- jessaustin 7y ago
  Horses can certainly be ridden without stirrups. In fact stirrups weren't invented for over 4000 years after the domestication of the horse. The Roman Empire had no stirrups. The hardest part of riding without stirrups is mounting. It requires some mixture of strength, coordination, and a cooperative animal to mount from the ground without stirrups. Once you're mounted, staying mounted is not much more challenge than staying mounted with stirrups. Yeah in deep water you either have to have somebody on the other side holding that gunwale down, or you have to pull yourself up on one end. Nobody boards that way from the shore, though. You just have it sitting in the water where it will barely touch bottom if you put all your weight in. Then you get in, and it's sitting on the bottom, balanced. Then you push off with a paddle or stick. The whole process is much easier than using a dock.
JackFr 7y ago
>It seems pretty clear that the development of the bicycle would've been significantly hampered by the fact that balancing on two wheels was: > (a) unintuitive as an idea with no analogue in nature or previous innovations > (b) had a marked learning curve > (c) that learning curve was separate and independent for each design. This! It's completely non-obvious that balancing will work and there is no analog in nature to copy.
- lovemenot 7y ago
  Skating was a thing long before cycling was. With enough forward momentum one can go quite far balanced on one ice-skate.
  - double0jimb0 7y ago
    Rotating wheels generate a self balancing moment that resists falling over... which has nothing to do with balancing on a thin blade.
    - jessaustin 7y ago
      For the purposes of this discussion, that's probably true. However, I wouldn't be surprised if some super-precise slow motion video of a skater gliding on one skate revealed small adjustments analogous to the steering motions of a cyclist.
mantap 7y ago
It does seem utterly counterintuitive that a vehicle that cannot balance by itself would be able to balance with the addition of a heavy rider elevating its center of gravity. Usually making an object top-heavy renders it even more unstable, and bicycles are not stable to begin with. And adding a rider on top of a bicycle does make it more unstable, but the amazing flexibility of the human brain allows us to transform that instability into stability, kind of like how modern fighter jets are intentionally unstable to make them more manoeuvrable. Bicycles are a marvel of physics and biology working together.
- Armisael16 7y ago
  Bicycles are entirely stable without a rider as long as they’re moving. The human is only really necessary to provide motive power. There are a ton of videos showing this. It is totally unlike the intentional instability of a modern jet fighter.
  - maaaats 7y ago
    That relies on the front fork being at an angle, though, doesn't it? If they made it straight down (which is the obvious choice) or pointing backwards, it would be much, much harder to ride.
    - habnds 7y ago
      Bicycles actually are less stable with a more angled fork. If the fork was perpendicular to the ground it would be very difficult to turn. the geometry of the ride type of a bicycle or motorcycle is really interesting [1] [1] https://en.wikipedia.org/wiki/Bicycle_and_motorcycle_geometry https://en.wikipedia.org/wiki/Bicycle_and_motorcycle_geometr...
  - mantap 7y ago
    Maybe in spherical cow land, but in the real world bicycles don't get very far without a human to maintain balance. It would fall over the first time it had to ride over a piece of debris on the road.
analog31 7y ago
I read a biography of the Wright Brothers, which pointed out that they spent quite some time and effort with their gliders, learning how to fly. So they were already skilled pilots before they attempted powered flight. The book suggested that this idea occurred to none of the other airplane inventors. There might have been a similar problem with the bicycle: Anybody who built the first one had no idea of how to ride it, and lacked the advantages of being six years old, namely closer to the ground and quicker to heal from minor injuries. What I want to ask: Why are we still waiting so long for the bicycle? There just seem like so many barriers to more widespread adoption.
- Robotbeat 7y ago
  > The book suggested that this idea occurred to none of the other airplane inventors. Gliders were pretty important for other airplane inventors of the era, as well: https://en.wikipedia.org/wiki/History_of_aviation#Heavier_than_air https://en.wikipedia.org/wiki/History_of_aviation#Heavier_th...
deleted 7y ago
[deleted]

tcmb 7y ago

If you saw off a disc-shaped slice from a log of wood, and it rolls a few meters, you experience first hand that a single wheel can balance itself. Some say this is how the wheel was invented in the first place [citation needed].

SiempreViernes 7y ago
Right, now stand on said disk. Turns out the you+disk system doesn’t trivially balance...
- tcmb 7y ago
  That's not a fair continuation of the thought, is it? Even balancing on an entire rotating log isn't trivial. The problem here is standing on a small patch of surface that is moving under you. The required insight for the bicycle is that, counterintuitively, a rolling wheel doesn't fall to either side. The axles, fork, frame, and seat are 'just' the elaborate way of mounting yourself to those rotating discs so that you can move along with them while sitting still.
woodandsteel 7y ago
That sounds like a unicycle, which is a hundred times harder to balance than a bicycle. The physics of how a bicycle balances itself when you are moving is very different than that, complicated, and quite unintuitive. Basically when the bike starts to lean to one side, the rotation of the front wheel causes it to steer to move the bike underneath the direction you are leaning. This happens several times a second, and faster than a human can react. https://www.citylab.com/design/2015/05/the-weird-wonderful-science-of-how-bicycles-balance-themselves/392690/ https://www.citylab.com/design/2015/05/the-weird-wonderful-s...
- lovemenot 7y ago
  >> ... a unicycle, which is a hundred times harder to balance than a bicycle. It's not that hard to unicycle. It just seems so to people who didn't try it until they were an adult. In Japan, any junior high school may have a few unicycles and you frequently see kids larking around on them in the playground. Nothing special.
  - wingerlang 7y ago
    Agreed, i think they take a somewhat equal amount of time to get going on. Probably takes a few hours over a few days on both of them to get going.
- jhrmnn 7y ago
  Anyone can experience this by overtightening the headset (the steering axis) on a bike. Suddenly one has to focus on balancing way more and riding a bike no handed becomes almost impossible.

deathanatos 7y ago

> The horse, with its four (not two!) legs is an even more ridiculous comparison. The comparison is, as I understood it, the rider balancing on the horse itself. I've only ever done this myself with saddle and stirrups, so I don't know if this is significantly more difficult without those. I think you're being a little generous with the canoe. Boarding a canoe without a dock (that is, climbing in from the water) is tricky, and requires some thought about where your weight is. (Since the lip of the canoe, in my experience, sits well above the water line, and you're about to pull down on the edge to attempt to board, but that same motion is the motion that moves the edge closer to the water which will flood it.) I've seen plenty of people flip and subsequently flood a canoe after an unsuccessful attempt to board.

JackFr 7y ago
But a canoe floats, as a horse stands. A bicycle simply does not stand up on its own.
- pbhjpbhj 7y ago
  Surely it can, it's just a case of finding the balance point? [Ignoring macroscopic effects of the Earth rotating, etc.]
jessaustin 7y ago
Horses can certainly be ridden without stirrups. In fact stirrups weren't invented for over 4000 years after the domestication of the horse. The Roman Empire had no stirrups. The hardest part of riding without stirrups is mounting. It requires some mixture of strength, coordination, and a cooperative animal to mount from the ground without stirrups. Once you're mounted, staying mounted is not much more challenge than staying mounted with stirrups. Yeah in deep water you either have to have somebody on the other side holding that gunwale down, or you have to pull yourself up on one end. Nobody boards that way from the shore, though. You just have it sitting in the water where it will barely touch bottom if you put all your weight in. Then you get in, and it's sitting on the bottom, balanced. Then you push off with a paddle or stick. The whole process is much easier than using a dock.

JackFr 7y ago

>It seems pretty clear that the development of the bicycle would've been significantly hampered by the fact that balancing on two wheels was: > (a) unintuitive as an idea with no analogue in nature or previous innovations > (b) had a marked learning curve > (c) that learning curve was separate and independent for each design. This! It's completely non-obvious that balancing will work and there is no analog in nature to copy.

lovemenot 7y ago
Skating was a thing long before cycling was. With enough forward momentum one can go quite far balanced on one ice-skate.
- double0jimb0 7y ago
  Rotating wheels generate a self balancing moment that resists falling over... which has nothing to do with balancing on a thin blade.
  - jessaustin 7y ago
    For the purposes of this discussion, that's probably true. However, I wouldn't be surprised if some super-precise slow motion video of a skater gliding on one skate revealed small adjustments analogous to the steering motions of a cyclist.

mantap 7y ago

It does seem utterly counterintuitive that a vehicle that cannot balance by itself would be able to balance with the addition of a heavy rider elevating its center of gravity. Usually making an object top-heavy renders it even more unstable, and bicycles are not stable to begin with. And adding a rider on top of a bicycle does make it more unstable, but the amazing flexibility of the human brain allows us to transform that instability into stability, kind of like how modern fighter jets are intentionally unstable to make them more manoeuvrable. Bicycles are a marvel of physics and biology working together.

Armisael16 7y ago
Bicycles are entirely stable without a rider as long as they’re moving. The human is only really necessary to provide motive power. There are a ton of videos showing this. It is totally unlike the intentional instability of a modern jet fighter.
- maaaats 7y ago
  That relies on the front fork being at an angle, though, doesn't it? If they made it straight down (which is the obvious choice) or pointing backwards, it would be much, much harder to ride.
  - habnds 7y ago
    Bicycles actually are less stable with a more angled fork. If the fork was perpendicular to the ground it would be very difficult to turn. the geometry of the ride type of a bicycle or motorcycle is really interesting [1] [1] https://en.wikipedia.org/wiki/Bicycle_and_motorcycle_geometry https://en.wikipedia.org/wiki/Bicycle_and_motorcycle_geometr...
- mantap 7y ago
  Maybe in spherical cow land, but in the real world bicycles don't get very far without a human to maintain balance. It would fall over the first time it had to ride over a piece of debris on the road.

analog31 7y ago

I read a biography of the Wright Brothers, which pointed out that they spent quite some time and effort with their gliders, learning how to fly. So they were already skilled pilots before they attempted powered flight. The book suggested that this idea occurred to none of the other airplane inventors. There might have been a similar problem with the bicycle: Anybody who built the first one had no idea of how to ride it, and lacked the advantages of being six years old, namely closer to the ground and quicker to heal from minor injuries. What I want to ask: Why are we still waiting so long for the bicycle? There just seem like so many barriers to more widespread adoption.

Robotbeat 7y ago
> The book suggested that this idea occurred to none of the other airplane inventors. Gliders were pretty important for other airplane inventors of the era, as well: https://en.wikipedia.org/wiki/History_of_aviation#Heavier_than_air https://en.wikipedia.org/wiki/History_of_aviation#Heavier_th...

deleted 7y ago

[deleted]