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Comment by calibas | Hacker News Reader

I don't think that's how a bike works.

You pivot the front wheel to turn, the leaning is secondary. It's to counter centrifugal force so you don't fall over.

Edit: I'm mistaken and didn't account for camber thrust which happens when "a point on the outer surface of a leaned and rotating tire, that would normally follow a path that is elliptical when projected onto the ground, is forced to follow a straight path while coming in contact with the ground, due to friction. This deviation towards the direction of the lean causes a deformation in the tire tread and carcass that is transmitted to the vehicle as a force in the direction of the lean." https://en.wikipedia.org/wiki/Camber_thrust

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So, to read into this, "countersteer" is the term that'll get you into a lot of discussion about this.

But, in-fact at speed, while pivoting the wheel will initiate the lean, the lean itself is the primary factor in steering the bike.

These weird unintuitive mechanics, are part of why learning to ride a bike with training wheels, or from a tricycle is so hard, the steering mechanism of a bike inverts from when there are 3 wheels on the ground, to when there is 2 wheels. And also a significant reason that "Balance bikes" have replaced a lot of tricycles and training wheels when teaching kids to ride a bike.

did the balance bike thing. my kid just yesterday is riding a real bike at 3 years old. just told him to get going and put his feet on the pedals and he was riding his bike in less than 5 minutes.

Nice job!

Balance bikes aren't even all that necessary and a lot of them are so poorly made that they aren't doing much of anything. Get a decent real bike of the appropriate size and take the pedals off of it (lower the seat so they can sit while both feet are flat on the ground).

Teach the kids to glide. That's it. Start with gliding a few centimeters and work up to gliding multiple meters/feet. Go at whatever pace is comfortable. It could take months or minutes. You'll know when the time is right to put the pedals back on and raise the seat. At that point, you are 5-10 minutes max from riding a bike like a pro.

For my oldest kid, I paid $50 for a "we will teach your kid to ride in ONE HOUR" class and watched them teach it (my kid took 45 minutes). Since then, I've taught little kids, older kids, adults. This stuff really works. It is seriously hard to believe that the old way of teaching people to ride bikes ever existed.

Yeah the balance bike was a present at 1 year old to gauge interest as he grew. Definitely not necessary. We went all out with a Strider 12 pro though. He was able to walk with it very early on but the 2 front wheel scooter captured his attention more. He loved riding on the Shotgun Pro seat though on our bikes.

The gliding is definitely the skill needed. It helps to have somewhere with a slight incline like a driveway apron too. At least it made it less boring for my son. The problem I see with the gliding is that it wasn't all that interesting to my son. So it really took him to get old enough to realize it would be a step towards riding a real bike.

What I can't believe is that the high end companies like Specialized, Trek, etc hadn't figure this out years ago. I can't believe they even still allow themselves to sell bikes with training wheels. I get that it's a short term sale for parents who don't know any better but you'd think they'd be better off if the kids actually learned to ride quickly and graduated to bigger bikes instead of maybe never learning to ride until much older.

They should sell the bikes with the crank arms that can pop on and off with a quick release and without actually taking off the front sprocket. Even taking the pedals off the crank arms are still in the way.

Here's a good video showing how a bike actually works, and the relation between steering and leaning:

https://www.youtube.com/watch?v=9cNmUNHSBac

It's kinda weird, but if you want to turn right for instance you turn the handlebar slightly left and then use the centrifugal force to lean the bike to the right and into the curve.

At least that is what i got from Flick of The Wrist, a kinda funny instructional video on riding bikes (it's on youtube) :)

No, I hate to disagree so unequivocally, but you pretty much never pivot your front wheel on a bike to turn!

I have a cargo bike with a lockable front wheel, and even if I forget to unlock that, I can still drive, even though it's unpleasant.

That unpleasantness mostly comes from being unable to turn my front wheel in the opposite direction before leaning in to the actual turn direction, though.

This is on a manually powered bike, though, so maybe things are different on a motor bike? But I sort-of doubt it, since the physics are the same...

I think, some confusion, at least mine, comes from comparing bicycles to motor bikes. I imagine you are right that initiating a lean with a bicycle without steering should be fairly doable. The confusion, is motobikes are much heavier, and with heavier wheels, maintain much stronger gyroscopic forces. So while I recognize the ease of your experience leaning a bicycle. It becomes much more difficult with a motorbike.

Bringing this back to the original post. Looking at this thing, I imagine it'd be hard to properly lean it given what appears to be significant heft.

Edit: To be clear, I mostly agree that it's the lean that's the primary factor in the turn. Just a subtle bit of confusion over how important steering is over initiating the lean in heavier bikes.

I can absolutely guarantee you that on a snow bike, leaning into the direction you want to go in is critical.

Turning the front skis (which have a range of, maybe, 20 degrees, not sure, never used them!) is discouraged, and probably doesn't do much, except in emergencies. Like braking!

And yeah, these things weigh around 200kgs (450 lbs), before occupants.

By awkwardly turning with the front wheel locked, what you're demonstrating is that your cargo bike isn't perfectly rigid.

The leaning is the primary factor when it comes to turning a bike. It's why forks are angled forward, instead of straight down. You can even turn while keeping the handlebars straight, just by leaning.

Watch some youtube videos of people turning while in a wheelie. The counter steering helps lean the bike, but it's the lean that makes you turn.

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