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Comment by geocrasher | Hacker News Reader

I taught my son to ride using training wheels. He rode around for a few days and asked me to take them off. So, I took them off. And when I came back outside from putting the tools and training wheels away, he was riding his bike as if he'd never not ridden it. I do like the author's idea however.

By the way, did you know that the the right pedal is right hand thread, but the left pedal is left handed thread? If it wasn't, the left pedal, being right hand threaded, would come loose easily. And that was a Wright Brothers innovation.

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Love this soundbite. I did not know this and will totally use it to sound smart at dinner parties.

On a somewhat related note, the reason why Peugeot cars have a "0" in their model numbers (e.g. 208, 308, 408, etc.) goes back to the days before electric ignition, and when you still needed a crank to start the engine. The model number was in the middle of the grill, and the crank would go into the "0".

Apparently the tradition continues. On our Peugeot 407, the button to open the boot (trunk) is in the "0" on the "407" badge.

There you go! I wonder what the very first engineer or "product designer" at Peugeot who came up with the idea would think today.

The problem with training wheels is that they train how to ride a quad, not a bike. On a quad, when you turn the handlebar to the left, you go to the left. On a bike, you fall to the right.

I vaguely remember my training wheels were set a bit higher and not touching the ground unless I was leaning a lot. So this setup would aid training to ride properly.

This is exactly the case.

I'm having a really hard time verifying that it was a Wright Brothers innovation.

I can find claims that it was so, but nothing substantial. For example, this 1959 kids book - https://archive.org/details/wilburorvillewri0000augu/page/17... .

On the other hand, I can find cranks which had reversed threads, pre-dating 1900, like US643349A filed 1895 where "The screw-threads on the parts b b' of the shaft are oppositely directed, or, in other words, are right and left hand threads".

It's described as protecting the ball-bearings, not to prevent coming loose.

https://www.wright-brothers.org/Information_Desk/Just_the_Fa... says:

> In 1900, the Wrights announced a "bicycle pedal that can't come unscrewed." Pedals were mounted to the crank by threaded spindles. On early bicycles, both crank arms had standard right-hand threads. As the cyclist pedaled, the action tended to tighten one pedal and loosen the other, with the result that one pedal kept dropping off the bike. British inventor William Kemp Starley had solved a similar problem years before when the right-hand cups that housed the crank or "bottom" bearing on early bicycles kept coming loose. He simply reversed the thread direction on the right cup so the pedaling action kept it tight. It wasn't long before bicycle makers realized the same solution could keep the pedals in place. Wilbur and Orville were in the vanguard of those manufacturers that offered right-hand threads on one crank arm and left-hand threads on the other.

That is, the Wright Brothers were early promoters of the design, but not the innovators.

You may be right. I read this on the late Sheldon Brown's website, and it stuck. References:

    https://www.sheldonbrown.com/tancrank.html
    Left-threaded pedals and cranks are reputedly an invention of the Wright brothers, bicycle builders from Dayton, Ohio. (They also built airplanes). 

    https://www.sheldonbrown.com/brandt/left.html
    The left-threaded left pedal was not the result of armchair theorizing, it was a solution to a real problem: people's left pedals kept unscrewing! We have read that the left threading was invented by the Wright brothers, but we are not sure of this.

So, I said it with more authority than was warranted. But it's good enough for normal dinner conversation references ;)

It looks like that method was known by 1880, if I read https://archive.org/details/indispensablebic00stur/page/14/m... correctly ('The "indispensable" bicyclist's handbook; a complete cyclopaedia on the subject') correctly:

> The Centaur Crank is first screwed up to a shoulder on the axle with right and left-handed threads, so that the pressure of the foot tends to make it all the more secure ; whilst, to prevent its loosening by “ back-pedalling,” a slightly tapered conical pin is driven through both crank and axle, and secured with a nut.

I suspect a lot depends on the age and motor development level that people here are not talking about, and that there should a certain age where a kid has not developed the muscles as much as to bike fast enough to pedal comfortably and fast enough to be able to balance, and an age after where, once one has figured how to pedal comfortably, balancing would not be that hard. I would assume that it would be harder to balance in the first place if you have to struggle putting force to pedal, which also probably means you cannot develop a sufficient speed either.

The training wheels on the bike I learned on didn't have an additional brace to stop them from bending. (they were basically an L shape, only supported at the top)

I assume that was helpful for me, as they gave less and less support as they deformed over time and I had to properly balance to stay upright. I was still quite surprised with myself after they were taken off.

It's actually to stop it being screwed in so tightly you can't remove it. The threads are such that in normal usage the pedals turn the same way you'd unscrew them.

Apparently it's actually an effect of the thread precessing into the hole. Interesting.

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