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It’s easy to build a rocket. It’s not like it’s bicycle-science

Bicycles: We must thwart all attempts to study us. If the humans find out we're sentient they wont sit on our faces anymore.

I just taught my 2 kids to ride their bikes last weekend, it’s amazing to watch them find their balance and know once you find it, you will always have it.

I was around seven when my dad bought me a bicycle and attempted to teach me how to ride it. He spent hours and finally gave up in disgust. In ten minutes, without dad there, I figured it out and within an hour on my own, I was pretty good at it. How to ride a bicycle is difficult to explain to another person, they just have to figure it out because of being somewhat intuitive.

"Sure, it works in practice, but does it work in theory?"

"Bro, check out this thing I just invented." 'Wack. What do you call it?' "A bicycle." 'How does it work?' "... you know, I have no clue."

"According to all known laws of engineering, there is no way a bicycle can remain upright. The bicycle does so anyway because it does not care."

In many ways, the bicycle was really far far ahead of its time. We don't fully understand how it works. But it does work, it's simple and robust and reliable.

"and, of course, it's boring to write it up" Our bicycle understanding is being hindered by how boring it is.

Every two wheeled vehicle (including bicycles, motorcycles, segways, ect) has it's own personal invisible gnome that runs beside it to hold it up.

Imagine knowing how bicycles work but then you think about it really hard and then don’t know how it works anymore

The hope I take away from this video is that we engineer a faster-than-light drive before we ever figure out if FTL travel is in any way theoretically possible.

“It just works”-Todd Howard

Simon, No one says “..easy as riding a bike” People say both: “Just like riding a bike” -in reference to activities easily picked back up after one has not engaged in them in a long while. And “Easy as falling off a horse”

I propose we use this when considering how advanced alien civilisations are. Stage 1: No Bikes. Stage 2: Bikes, But How Do They Work?? Stage 3: ???

One property that was not mentioned is the fact that the geometry of the front steering is arranged so that when the steering is turned, the center of gravity of the bicycle is raised. This effect will give a self-steering effect as the raised weight will try to go back to the minimum height when the steering is not turned. This is achieved by arranging for the castor angle to set its hinge line such that the hinge line projected line will project down to meet close to the point of contact of the wheel with the ground. There are other factors to consider. The turning of the steering will displace laterally the centre of gravity of the bicycle so that CG oscillates about the line on the ground joining the front and back wheels. It is this oscillation of the center of gravity of the bicycle about the line joining the point of ground contact of the front and back wheel. All this is related to a tight rope walker riding a bicycle on the rope handling his own weight shift or that of a pole. Rather than turning the steering wheel to change the center of gravity about the tight rope, all the driver does is change his weight above the tight rope laterally to the tight rope below him. Since the footprint below a bicycle is always a thin line then the center of gravity must always oscillate about the line. All one needs to do to check this is to keep the bicycle stationary and turn the wheel to the right or left and one can easily note that the center of gravity is changing. Also, the steering of a bicycle needs to be turned in the direction of the fall WHERE THE RATE OF CHANGE OF THE TURNING OF THE HANDLEBARS MUST BE FASTER THAN THE RATE OF FALL OF THE WEIGHT. I find it difficult to believe that the mathematicians of the earlier centuries could not see these three-dimensional mathematics. Note that the self-steering of a car is related to what was said above. The weight is lifted when the wheels are turned and when the steering wheel is free the weight of the car will drop down to the minimum height which is when the front wheels are pointing straight ahead. It is very interesting that the projected hinge line with the point of contact changes with the inflation of the tires and so one should keep the tires blown up at the right pressure, for there are situations when the steering is turned beyond an angle the steering becomes unstable and does not return to facing the front, When trying to understand the steering of a bicycle or a car, do all movements very slowly as there are at least three procedures going on at the same time. Note again the raising of the CG which this video did not mention. Note that the gyroscopic effect of the rotating wheels of the bike is minor and can be totally eliminated at the slow speed we normally ride. It is the shifting of the CG about the line of wheel contact with the ground and the rate at which the handle is turned with respect to the falling of the CG. so that the CG jumps over the line joining the contacts points with the ground of the front and back wheel.

In 2020 we will have flying cars 2021: We still don't know how bicycles work

After trying to distract myself from the fact that I've had three bicycles stolen from my shed today, the youtube algorithm puts this in my autoplaylist.

"Science is inherently interesting, but writing things down is boring." - Jim Papadopoulos Even without reading his ridiculous surname, you could tell this man has Greek heritage from that quote alone.

There's not a single force that keeps a bicycle upright in motion. It's a combination of forces. If you were to eliminate gyroscopic procession and run a bicycle on a treadmill, it would become far less stable, becoming completely dependent on the auto righting feature of the angle of the fork. When a motorcycle achieves high enough speeds to overcome its aerodynamic engineering, the air pressures overcome the gyroscopic procession and the bike becomes unstable. You're basically combining the forces of a gyroscope, a paper airplane and pendulum when you are riding a bike. (Gyroscope = wheels, paper airplane = air pressures due to the flat plane design of the vehicle, and pendulum = the steering angle and its predisposition to right it self /fall to center)

As a child, I had two skinned knees that disproved all theories of stability.

"Gee why is it called a safety bicycle if people get hurt on it all the time?" *Sees Penny Farthing* "Ah, right, relatively safety bicycle."

The bicycle is one of the longest standing “of it ain’t broke don’t fix it” examples, we don’t need a bike with power steering and AC 😂

Wow, Johnny Sins has grown a beard and has ventured into yet another discipline - a youtube presenter. So versatile and talented, this man.

"Oh so you like physics? Explain a bicycle"

Wish you'd included images of all these interesting-sounding experimental bicycles!

I thought to myself reading the “clickbait” title: I’ll bet my college-level physics books knows how bicycles work.

After seeing this video, I have to wonder: is the same true if you propel the bike with the back wheel first (obviously allowing it to spin freely this way). Something tells me that the bike will be terribly unstable if you try that, but that might just be due to reverse cycl'ology.

The only saying does not go, "as easy as riding bike." The old saying is, "it's like riding a bike." ..Not because it's easy, but because if you learn how to do something (ride a bike), even if it's been a long time since you've done it, you can pick it up again as if you've never stopped. That principle tends to apply to many things, and so the saying was born.

I haven't driven a vehicle in a decade. All I do is bicycle. I'll bike up the mountain tops in colorado. From Kansas. I bike all my groceries home on my back. I'm constantly burning through bike parts. Just like cars, they fall apart. I bike to work I bike for leisure I bike for any and all appointments. I have an intimate understanding of how a bicycle behaves. With impeccable balance the bike doesn't even have to move. If you're really good you can remain balanced immobile indefinitely. As soon as a stationary bike has spinning wheels it's already gaining stability (not full stability) by angular momentum. Not gyroscopic precession. The precession actually destabilizes you. The precession is the twisting upon it's axis as friction is applied to a point on the axis. the ratio of the mass of the wheels to the mass of everything else and center of gravity are key. My 29inch wheels bike is stable at slower speeds than my 20inch wheels. Also my 20 inch wheels can cut a hard corner at high speed. 29 inch wheels at sufficiently high speed you can't physically push that handlebar to do anything but minor course corrections. Anyone with a motorcyle knows what I mean. That's angular momentum. Everything moving in a straight path forward resists a change of direction proportional to its velocity. Here's a key component literally everybody has overlooked. Ready? The bicycle is a twin axle vehicle. Yes just like your car. Each wheel has an axle albeit not a very wide one. So your application of forces works in tandem across both sides of the fork. You can't think of a bicycle two dimensionally and expect to solve the math problem. When you steer right you're not twisting a center point of the wheel. You're pushing the left for forward and pulling the right fork backwards. Which torques the entire wheel from both ends of a gyroscopic axis. The back wheel acts as a gyroscope mounted in a fixed position and trailing along for the ride. That's two independent systems working together. The fixed rear gyro. The front fork working across an axle. You could imagine each wheel is actually two conjoined rims with a round bubble between them. The tread is variable. Some treads are rather flat effectively granting two beads of traction or "tracks" or "trails" or whatever the video just said. A cross section of an inflated tube is only round if it's not pressing against anything. The weight of the bike already widens out a path of contact more indicative of a small circle than a point. A fatass atop the bike with reduce tube pressure would initiate a a rather large plane of contact with the ground. This is important. Friction with the ground also causes stability. Send an empty bike careening forward angling off to one side and see what happens when it hits an oil slick. Yes the bottom flies out from under itself. Suddenly all stability was lost. My knees know. Don't ever bank a hard turn over a patch of fresh new smooth cement with loose sand on it. You'll learn a lesson or two in gravity real quick.

Very interesting that this is all on the most basic rigid bicycle on flat ground. I can’t imagine how much more difficult it would be to explain a full suspension on complicated terrain.

I'm skeptical that the counter gyroscopes disprove their effect. IT's not like a helicopter where the gyroscopic effect is to spin the copter and can just be reversed by another scope. That's not what the gyroscope in a bicycle wheel is doing

5:20 Oh come on, the casters on shopping carts don't automatically align. On most carts, one caster just wants to spin around as you push the cart.

Engineer 1: Just created this incredible, affordable, simple vehicle, made of, like, 5 moving parts. Then we improved on it for over a hundred years. Engineer 2: Cool! how does it work? Engineer 1: idk lol

Did a class project on bicycle stability in Mech. Engineering class--it's surprisingly complex and difficult tho I managed to understand and explain most of it. It was entirely optimized via trial and error and can't be improved on, it can only provide trade offs between, say quick handling and high speed stability. 5 or 6 geometric/mass factors involved.

I’m no mathematician, but I do have a decent grasp on physics and having looked at David Jones’ bicycle, I do not believe in his assertion that gyroscopic properties are unimportant. All he did was attach a second front wheel that does not touch the ground and spins in the opposite direction, but is otherwise oriented exactly the same as the original front wheel. If this newly added wheel were to have any affect at all, I believe it would improve stability, since there is now more mass spinning about a central point on the bike. The direction that the wheel spins has no bearing on it’s ability to stay upright nor would it “cancel” the others. It seems that the gyroscopic theory working in tandem with the way a bike steers into it’s fall makes perfect sense. It doesn’t have to just be one variable that is the key to how it works. The whole bike is a system. I could be wrong but it seems like David Jones’ dismissal of gyroscopic bicycle theory is based in a lack of understanding of gyroscopes. Would love to hear thoughts.

Me seeing the title: Duh, peddles turn chain turns wheel. Me watching: ohhhh

Humans: “We ShOuLd CoLoNizE MaRS.” Also humans: *can’t figure out how bikes stay upright

Side note here, David Wilson was not the inventor of the Recumbent Bicycle, that was Charles Mochet in the 1930's. First his Velocars, then the first performance Vélo Couché. A Recumbent (Nazca Gaucho) and a Quest Velomobile are my normal bikes 😉 Taking the Gaucho to Zürich this week, cycling & camping to the Recumbent World Championships in Lustenau, Austria. All races under our own IHPVA & WHPVA organisations, because the UCI doesn't consider our vehicles legal... 😏

“Mathematicians began to seriously investigate the mysterious physics of the bicycle’s remarkable stability.” Great sentence. Should be a rap.

I have NEVER EVER in my 34 years alive thought about this until now and im am thoroughly annoyed by it.

British comedian Dara O’Bian: “Science knows it doesn’t know everything. Otherwise, it would stop.”

I used to work for Bicycling Magazine in the 1980's. I met of heard of at least half of those engineering types. I met one Crispin Miller, who knew (probably) all. As the low man on the totem pole, all this math boggled the mind. I learned to see geometric differences in bicycles at a glance. At this time, Mountain bikes were evolving from downhill coasters to all out performance bicycles that could handle everything Earth threw at them. The 80's were a remarkable time for the sport. As an elder, I still ride... not the 200-300 miles per week... but per year... it's a goal now. Loved this video. Will share with former coworkers.

If you hold a bike wheel in each hand by the axle and spin it, then it's very difficult to turn it left or right. If you let go with one hand, then the wheel doesn't fall to the ground, it starts to twist around the hand that's holding it, that's precession. I've always thought it quite spooky and inexplicable.

As an engineer, I find some of this to ring as rather misleading. Someone concludes that bicycles stay upright through the "caster effect" due to the front fork having a "positive trail." This does not mean that A) only two wheel things with positive trails are stable. Or B) There are no "negative trail" designs leading to stability. Physicists and engineers can easily calculate the effects of precession from the spinning wheels. We know it contributes slightly to stability. The caster effect helps self-correct a falling bike. In my mind, that explains the phenomenon fairly robustly. Because some PhD can design a two wheeled device that cancels out the gyroscopic effects of the wheels and has a "negative trail," but compensates for these design changes by having a LARGR MASS BEYOND THE FRONT WHEEL, I see absolutely no reason to then make the claim, "therefore physicists still don't know how bikes work." It screams of dishonest interpretation of the experiments. Perhaps there is more going on here; I afterall know nothing about bicycle physics. But just based on what he said and how he presented information, I feel it is rather misleading and trying to cause a stir or a mystery around something rather commonplace in hopes to spark curiosity and generate views. But this video sounds only a few degrees better than, "This one weird trick has Harvard linguists mad" to me. We could make any sort of video: "Physicists still don't understand vacuums" and then drag out the unsolved, full Navier-Stokes equations of fluid dynamics, but what are we really saying at that point?

Now...if they could just design a comfortable seat.

I think a big part of why the mystery remains is that studying it is not worth economically, since bikes anyway work. This reminds me of the theory of planes, which was at least wrongly understood and explained in pilot schools during most years of airline companies. Also, makes me think of Swifts and the fact that they seem to sleep in the air, but we have no idea of details... who would invest in researching that? The story of Papadopoulos being late even when the matter was his passion, and in the end losing it all, truly hits home :D

The bicycle is one of the best inventions in history;

“So you spent 10 years on your PhD! What did you study?” “How to ride a bicycle!” 😳

This engineer who submitted an essay two years late is my kind of guy. We'd get on well.

"Mathematicians began to study the physics of the bicycle." No wonder we don't understand how they work. I have heard the goofiest, most wrong explanations for real world phenomena from mathematicians. Mathemeticians that work at the same physics lab as I.

The problem so many people seem to have is that they're looking for a simple, single answer for everything when bicycle stability is a complex interaction from multiple forces. Even with counter-rotating wheels, a gyroscope is still a gyroscope. You might cancel out the direction the axle want's to turn, but the gyroscope still doesn't want to move its axis. You can build a bike that doesn't need positive trail but the castor effect still works. And I missed any mention of wheel flop; the tendency of the front wheel turning in the direction that the bike leans when stopped. Even if you cancel out one factor there are still other forces influencing stability. That doesn't invalidate the first factor. Pythons have small wheels with minimal gyroscopic effect, negative wheel flop and several inches of negative trail, but the configuration of the pivot uses the rider's weight to stabilize the bike. It's a lot more than "This one thing does all the work."

Silly boy, bicycles work because of... Magic.

"It's as easy as falling off a bicycle.'

Bicycles work based on momentum. The greater the momentum, the stabler its travel. It's like a coin. When it rolls, it rolls straight until it loses momentum, of which it will descend into a circular roll to one side or the other until it is eventually stopped, landing one of its faces. Bicycles, on the other hand, stop almost immediately, toppling over, because it is a dual wheel system. One wheel depends on the other for direction. If that direction is to acute to turn, the bicycle falls in on itself. If momentum is lost to a certain degree, the bicycle will fall over.

As someone who still can't ride a bike cause I could never understand how a bike stays upright, I approve of this video

I didn't know we were looking for the Grand unified bicycle theory.

"Allowing all four wheels of a shopping cart to steer at once." That's funny. The rear wheels are fixed. And in my experience, there is always one front wheel that does whatever the fuck it wants to. EDIT: I'm informed that in some parts of the world shopping carts (trollies, buggies, caddies) have four castering wheels. Great for drifting around corners I assume.

I love how the things that break science the most aren’t the things on the frontier of human technology but its stuff like bikes and dominos and breaking spaghetti Smarter every day reference

When riding a bike, you find that if you're falling to any side and turn the steering slightly towards that side, you regain balance. A bike in motion on its own does this as well. If it leans in any direction, its steering obviously falls slightly in that direction as well, stabilizing the bike. Perhaps I'm being too simplistic but it's always made sense to me.

I think it's in part due to the minor gyroscopic force of the two rotating wheels and the self correcting is a moment of force. Where the front wheel can't topple the rest of the bike so the rear end straightens the front tire. The opposing weight of the rear end counter balances the front. It is a bit more complicated than that, but thats basically it. If you fix the steering of a bike it would fall over, the ease of movement in the front wheel is in part the cause of the self corrections.

Why can't bicycles stand up on their own? They're too tired.

"Th" in German is pronounced "T" by the way. We do not have the English "th"-sound.

The caster effect is probably still the answer, kind of, but they debunked it the wrong way. As long as the wheel is angled it doesnt matter which direction, it will be stable due to friction of the wheel forcing it to straighten out if it turns. A straight up fork, 90 degree caster would probably be unstable. Try to ride on ice and you realize quickly how much of a bikes stability is based on friction.

This guy can do a 5 minute video in just 12 minutes. Talent.

The most important thing I learned working in bike shops was how little most people know about their bikes. The second most important thing I learned was how to not be a dick about that. (Edit: I'm surprised this comment is still getting replies. Seems like a lot of people found my comment to be judgmental. It's not. Theres plenty of things I don't know and plenty of jobs I'd rather have a pro do.)

Ski bikes disprove most of the past explanations of how a bicycle works. The best explanation to my thinking is kinetic energy. Mass in motion tends to stay in motion. For the mass to change direction, as in falling over, would take additional energy. Energy takes the path of least resistance. For that it is harder to fall over than it is to stay upright.

I think what has been forgotten is that all vehicles pre-dating the "radial" tire used a negative caster alignment on both front wheels. Only after the radial tire was mainstream did vehicle manufacturers change alignment of caster to a positive alignment. The tires are the reason why this change was necessary. All bicycles as far as I am aware still use a Bias-ply construction which doesn't necessarily require negative caster but polyester chord and Bias-ply constructed tires "feel" more stable with negative caster alignments than with positive caster alignments. I think bicycles are using both gyroscopic forces and "caster" alignment to achieve a self stabilizing ability.

Easy, we're living in a simulation. The player put in a cheat code that grants physics to bicycles and bumblebees.

*Scientists:* "We know how the very universe we live in came to be!" *Scientists:* "Yeah, we still have some questions about how bicycles work."

Disappointing that they showed no examples of these experimental bike designs. This could have been a very interesting subject to cover but the video seems rushed and the presenter talks a little too fast at times.

I wonder if bicycles stay upright due to the "unstable system" theory. Basically, as the bicycle's wheels spin, the top of them try to fall over, but (moving at a decent rate) the top soon becomes the bottom, thus the top's downward inertia is either canceled or redistributed as the bottom becomes the top and also tries to fall over. This constant shift of inertia over the entire circumference creates what I think can be considered an "unstable system", which has been already shown to create rather interesting gravitational effects due to an object's mass not being able to settle towards any particular direction of "falling".

Sadly, I don't think anyone would get a Nobel prize for cracking this one.

I worked as an engineering technician for many years and I can tell you honestly we wouldn't have bicycles if someone tried to invent them today. Why, because I have run into far too many engineers with the attitude that, it didn't matter that we had a working prototype, unless we could prove the concept on paper it couldn't go into production.

I happen to think that a far more relative force is camber. I am a mechanic by trade and do alignments all the time.One thing that can cause a pull is both front wheels being off in the same direction in camber. if they are both to the left the car will pull left, and the to the right if it is opposite. The tire being at a slight angle causes drag on the side that has more pressure, and pulls it in that direction. I believe the action of the front wheel is the result of this movement and position on the ground. Once the bicycle is going too slow the wheel can't move fast enough to right the vehicle, though YOU can if you are riding. Above a certain speed the movement of the vehicle out of camber makes a far faster movement of the front wheel causing the vehicle to remain upright.

Gryoscopic effect. The 2 rotating wheels are gyroscopically stable until they slow down enough to unbalance the bike. there is right now a roller set you can buy that allows you to simply place your bike on the rollers and make your regular bike a stationary bike, and its very difficult to get started as you have a stationary bike thats unstable, but once you get the wheels up to speed, the bike is no more difficult to ride than if it were on the road. And ofcourse the bike is unstable if the fork cant move. If youve ever seen a gryoscope, it needs to be able to move in order to correct itself.

While quite interesting and somewhat informative, I would have liked to seen more visual representations of the theories and ideas discussed.

Isn't it weird we had trains before we had bicycles? Wtf.

I'd like to see those run-along, hobby horse styled "bicycles" go Xtreme

Its just stearing geometry. When the wheel turns right, it tilts the bike left, whitch makes it stear left, whitch makes it tilt right, whitch makes it stear right whitch makes it tilt left, so on...

The reasons behind this phenomenon are simple. Ghost enjoy riding bicycles when the opportunity presents itself

That last burn. Dude called everyone out, worrying about dark matter. Dang.

I never knew this. I always just assumed the foward movement, combined with gravitational force balanced the weight of the bike, allowing it to "ghost ride" made sense to me, still does, would definitely explain why it doesn't stay upright on its own when the bike isn't moving. I feel like this is a simple problem, that only hasn't been solved because anyone who's actually taken the time study, assumed it can't be something simple.

"Objects in motion, tend to stay in motion" I thought we covered this. The rotation of the tire pulls it straight, momentum, designed correctly of course. I feel like this is being over analyzed

As someone who rides a bicycle very regularly (yes, I am Dutch), this was really fascinating. I had no clue there are people actually trying to improve upon the standard design, nor did I know said design was as old as it is!

“Whenever I see an adult on a bicycle I have hope for humanity.” HG Wells

Well.. we do know... that's why we use the forward "caster" which makes the bicycle more stable. we use a slight forward caster in setting a car's wheel alignment for the same reason. It has to do with the tire angle causing the center of the tire to try to move faster than the edges. The same principal that makes a band saw blade stay on the wheels (they "crown" the "tires" on the wheels the blade rides on) Combine the crown with the forward caster and you get positive stability. Reverse the caster and it gets unstable.

Ok.. I am currently 2:23 into this video... The question is how does the bike maintain balance at a higher speed? Centripetal Motion doesn't explain this? The wheels themselves are being thrown in a circular direction with a direct rebound off the ground. This rebound pushes back up on the bike equally to the bike pushing down on the ground. That force is then centripetally directed around and outwards of the wheel, which includes making the bike stand up straight as the force is moving in a tangent to the wheel. The reason this causes balance and not for the bike to go any other direction would be simple, gravity. Gravity pulls the center of the bike down while the motion of the wheels tries to throw it in several directions including bouncing off the ground which would be vertical once again. So you have an equal and opposite amount of Vertical acceleration with a bike sitting still on the ground. With this, if you were to add the energy from the wheels in other directions... it then pulls the bike into a channel. Not to mention the faster you are going the rubber on the wheels is then touching the ground with les Width. Same with a tire on a car but it's more extreme on a car. But with more of the rebound being directed around the tire at an accelerating speed... the bike then rests on a much smaller width of tire. This enhances the effect of the channel that the center of gravity, the rebound and the centripetal motion are affecting the bike at the higher speeds. A gyroscope is a good reference for the centripetal motion of the wheel. Or a top even. Give the gyroscope more friction and it will have a harder time maintaining balance. So the lack of friction on the wheel of the bike, is what keeps the other principles affecting the outcome of the bike's balance. If I had the money, and the equipment. I could run some experiments to test these hypotheses, but I think if you use a little intuition you can see what I am getting at. One of the best ways to test the rubber of the tire affecting it's balance would be to use the same bike with both a tire and something solid on the wheel. If the bike with a solid surface has a harder time maintaining balance, this shows that the ground is indeed making more contact with the wheel and therefor the friction is now spread across the entire face of the wheel, where the tire is being affected by the same friction in a smaller area giving it less effect on horizontal frictional affect. So as I mentioned earlier the centripetal motion of the rebound from the ground pushing on the tire is more centered on the tire, giving it an equilibrium with the gravitational forces. It's not 100% effective of course but it is obviously noticeable when you push a bike with no one on it. Now... this is my uneducated brain speaking. Let me watch the video and see if any of my ideas are contradicted by the science.

"Well you got me. By all accounts it doesn't make sense." Kronk, talking about bicycle physics

I've done hundreds of hours of research, and I'd like to announce my findings: Bicycles work by pedaling your feet in a circle.

It would be nice for a supplier to supply mix+match bicycle parts for people to build bikes of their own size, gearing, braking, and wheel types.

It's 2 gyroscopic forces tied together and mass in motion moving along a linear path. If both the front and back wheel could pivot like only the front wheel does it would try to do a peroett and fall. But the fixed trailing wheel steers it straight and the gyroscopic force and the camber of the front wheel make it impossible. Just put the front forks perpendicular to the ground and it all falls apart. It's all a trick like the carnival rope lader or the sledgehammer and the bell at the top of a pole. I tell you how to ring the bell. Carnies will hate me for this but it's simple. Just hit the see saw board that launches the weight right on the edge with just the front edge of the Hammer . Don't hit the pad square on center. You want the most leverage you can get so you hit the edge of the lever where it is longest .the same goes for the hammer it to is a lever and you want it to be as long as possible.

4 old guys in a pot bar in Amsterdam, "We're the bicycle research institute, man!"

"Allowing all 4 wheels to steer at once" WHEN?

I think it's mixture of friction and gravity that uses a conservation of angular momentum. The case of a bicycle being able to balance straight is not what is truly amazing. It's it's ability to lean and turn as well as turn in tight circles at slow speeds by leaning into the turn. In this case gravity is pulling down. Anglar momentum is pushing outward and friction is pushing inward. Think water in a bucket revolving around you. Water stays because angular momentum and the strength of the bucket keep the mass of the bucket stationary relative to the bucket and why nascar has an incline on it's turns to prevent cars from flipping And a buck self rights itself because the least rolling resistance is when the wheels are inline with eachother. When the bike is moving forward it the Handel bars are turned the friction of the wheels being slightly out of alignment will pull the wheel back into being straight. A similar concept causes a bike to turn if its the center of gravity is moved to the left or right of center.

I think they should start with figuring out how one-wheeled objects stay upright such as a unicycle or even so simple as a coin. The momentum thrusts it forward along its side, but it falls if the side surface is not flat. Without a stable side to glide upon, the one wheel turns hard into whatever side it favors and basically spirals into a fall onto the ground. It's missing a force to counteract the slip into the fall. It's obvious from previous studies that the second wheel has great stabilizing properties in which it naturally turns into the fall similar to the physics of a trailer. I believe the answer to the rest is in the momentum's force pushing the bike forward and the same logic as a trailer where it reverses the fall by trying to turn to the way side out of the way of the second wheel that it will never be able to escape due to its fixed distance from it. As a result, the second wheel does not accomplish moving out of the way of the momentum coming from the rear, it instead counteracts the direction the rear wheel is wondering from; and so, the bicycle straightens out into an agreed direction until the momentum dies down and gravity defeats the forward force resulting in a harder and harder turn into the fall until the friction of the wheels give out and the bike falls. I understand that there are in fact bicycles that have no turning point on the structure, especially with early, experimental models, but those bikes are far less stable and depend much more on the rider's abilities. Without a rider, I'm sure it would lose balance significantly sooner, if not instantly, much like a single wheel would. Due to the fact that there were experiments where designers built a bike to completely neutralize gyroscopic forces, I believe that the gyroscopic forces of the wheels may be present, but not in an impactful way to the bike's ability to be thrust forward without falling. I have a theory that due to the wheels' vertical orientation, the gyroscopic forces do not stabilize its horizontal movement out of balance.

Me: "How does a bicycle work?" Todd Howard: "It just works!"

I didn’t hear the conclusion as being “we don’t understand how they work”, but as, “how they work isn’t adequately or fully explained by the more simple-minded ideas.” There are equations of motion that accurately model how bicycles work, and based on that, one can do computer modeling and create innovative designs. It’s not a “mystery”-it’s just not simple.

really some simple newtonian stuff here. leaning a moving bicycle causes friction, combined with steering geometry (negative or positive trail) causes the front wheel to steer into the lean. an upright position while rolling is simply the path of least resistance for the forces involved.