I never quite understood why it is so much easier to keep a bike balanced while riding at a certain speed, compared to riding it really slow, or while standing…
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It’s to do with the geometry of the front wheel axle. It’s pretty hard to explain without pictures, but I found this video that’s actually great.
Lot of interesting responses here but it has nothing with steering or gyros, its just angular momentum.
When the bike is going forwards, it’s vector of momentum is straight forward matching it’s vector of movement, meaning that no net acceleration is being applied laterally to it. You can steer how you like.
When the bike starts to tip over, it naturally tries to move to steer to one side or the other, that’s why you can steer by just leaning if you want.
While you are leaning/turning, the vector of movement is straight forward where the bike is now pointing, but the vector of momentum is still pointing near where the bike was pointing before. This means that there’s a net force on the bike sideways pushing it back upwards. This is why it’s naturally correcting.
Next time you are riding your bike, try steering by just leaning and notice how you don’t fall over, and the bike will self correct. Then lean over while stationary and watch yourself fall over :p
Essentially, you are falling forward instead of to the side. The top of the bike tires fall forward, going down to the ground, as your weight pushes them that way. But since they are designed to roll, you just keep going. And as they roll, it’s very easy to make tiny adjustments to their direction to keep them rolling straight instead of to the side, by steering and shifting your weight. Those adjustments can happen fast enough and are small enough so that the wheel stays straight up and continues to fall forward instead of to the side. As you slow down close to a stop, though, you desperately try to steer to stay up but the wheel is going so slowly that it can’t react fast enough and you wobble more and more.
bottom line : scientists don’t know.
it was thought that it was gyroscopic forces (the forces that make a spinning top move around) from the wheels were responsible, but they built a bike that cancelled all those out and it still worked fine. there have been other hypotheses, but nothing has been scientifically proven. it’s probably not magic, but for most of us, it might as well be.
The position of the front wheel relative to the steerer tube (the part of the frame at the front between the handlebar and the wheel) causes the front wheel to ‘want’ to turn in a direction that will keep the bike from falling over.
You can see this by pushing a bike with your hand on the seat. It will tend to stay upright, and you can steer it by leaning it one way or the other.
Believe it or not, we actually don’t know completely. this is an open question. For a long time we thought that it was because of gyroscopic forces, angular momentum, but that’s not the whole equation. I think veritasium did a episode on it.
It is called a gyroscope. The wheel rotates and can levitate. The best experiment is when a string is attached to the hub and the wheel spins, the wheel can be levitated by holding just the string rather than falling down. As soon as the wheel stops spinning, the wheel falls back down.
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Destin from Smarter Every Day did a great bit on how you get hardwired to keep a bicycle upright.
And you can’t undo it. On a special retrofit, he geared a bike’s steering to go left when turned right and right when turned left. People were unable to ride it. Even when offered money.
noone here is explaining it “like im 5” just say it simply and without writing whole essays
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