That's countersteering [1]. I find it very hard to explain but it's something that most people on a bicycle (at speed) or a motorcycle (again, at speed) do naturally.
I'd like to especially highlight your 'at speed' point here. It's often claimed that _all_ steering on a bike requires countersteering, but that is false. Countersteering allows rapid change of direction, but if you're going in a straight line, then lean left and gently steer left (or just lean left and allowing the front wheel to steer itself), you _will_ go left, no countersteering required.
Motorcycle courses put a lot of emphasis on countersteering because motorcycles go much faster and weight a lot more than a bike so you need to familiarize yourself with the effect from the get go unlike regular bikes where you generally start by going very slowly and the low bike-to-meat weight ratio means that it's relatively easy to steer by leaning with your body as you mention. As soon as you go over, say, 20km/h it's critical to learn how to countersteer properly if you want to keep control.
Try turning on a 200kg motorcycle going at 100km/h by simply leaning on it, you'll be disappointed... See for instance https://youtu.be/8_5Z3jyO2pA?t=2m24s . Later on the video they show that letting go of the handles and leaning with your body also works but only because it actually causes the bike to countersteer "on its own".
Yep. It is even more pronounced on a race track with long sweeping turns, even higher speeds, and nothing else in the world to worry about# (like traffic). The faster that front wheel spins, the more it wants to keep on doing that just as before (gyro).
You will be physically pushing the left hand and pulling your right to set the bike up for a left turn, not just "thinking" it - so as to speak. Of course it is entirely intuitive, until perhaps you stop to think about what actions you are taking, and then realise yeah that's countersteering all right.
#) It's been a few years for me now and I only got a few ride days in after also completing Superbike Cornering School lessons, but I found the art of riding my (then) 600cc GSXR motorcycle on a high speed circuit (Phillip Island) extremely meditative - and exhilarating, especially after learning the function of the knee sliders to assist with controlling lean.
If you lean left, front wheel will "do" countersteering itself (same as noted). Since gyroscopic effect on bike is not so big and speed, mass is not bigger than rider it is not noticable. For motorbike you cannot just lean hence need for explicit countersteering because of much higher forces involved.
So I think it is correct to say that countersteering is always required.
>If you lean left, front wheel will "do" countersteering itself (same as noted).
I am not sure. If you lean left, then the handle bar ll slightly turn left automatically.
In actual countersteering, it greatly helps only because it helps to quickly initiate a tilt in the required direction. For example, if you want to go to left, then turn the handle bar to the right, which causes the front wheel to slight start to offset in the right, which in turn causes the whole bike to tilt to left, and once it start to tilt to the left, then the normal process of turning is applied...
It's always countersteering. Doesn't even matter if your hands are on the bars (really).
When you lean to (your) left, the center of mass of you+bike goes left of the plane of the wheels, this causes the front wheel to rotate away (i.e. right) from the motion slightly which causes you to bank left and the front wheel comes around to meet it until you are in equilibrium again.
Countersteering doesn't "help", it's just unavoidable. Being aware of it helps you have better control. At very low velocities the effect is so minor you probably can't notice (and steering angles are large).
Why does it cause the front wheel to rotate away (right) ?
Answer is : "it's complicated" , which is why this subject causes confusion. There are many arguments about the exact dynamics (combinations of gyroscopic effects, torques, center-of-mass motion), but empirically it is pretty clear that two wheeled vehicles like bikes/motorcycles do not turn without counter-steer.
The part you are missing is the gyroscopic procession from the wheels. When you try turning the wheel to the left, you create a force that is 90 degrees to force.
If you just turn the handlebars (which would cause the bike to lean in the direction of the turn), you will end up creating a force at the top of the wheel in the opposite direction of your tilt. (e.g. the force will be at 12 o'clock)
If you just lean in the direction you'd like to turn, the wheel will turn in the opposite direction of the lean. (e.g. there will be an opposite force at 9 o'clock)
In order to turn you must always briefly steer in the opposite direction you'd like to turn, so that you may lean in the direction you'd like to turn, which will allow you to turn the wheel in the direction of the turn without upsetting the bike.
I learned this fact about 2 years ago and I've been hyper-aware of the fact ever since. Try as I might, it's literally impossible to steer a bike without counter-steering.
The fact that you absolutely must counter-steer to turn is one of the reason why inexperienced bike riders tend to fall over when they need to steer in an emergency, because they just twist the handlebars, which catapults them off the other side.
Knowing this also helped me finally learn to ride a bike with no handlebars, since you have to lean opposite the direction you'd like the wheel to go.
It's timing dependent. Turning right and momentum 'pushes' your body to the left, but with the correct timing you end up countering that force while keeping the bike absolutely vertical.
PS: Picture how a car turns, the wheels are vertical and you can you can turn without counter steering just fine but the weight externally offset. The difference with a bike / motorcycle is just how difficult it is to balance.
It is not timing it is balance of mass and conservation of energy. Car has totally different mass distribution. So energy conservation is also different.
The only time you steer left to go left is if you're going so slowly that the only reason the bike doesn't fall over is because of your near-superhuman balance. That is to say, when you're practically at a standstill. Anywhere approaching walking pace or above, if you try to turn left by steering left, you'll fall off the right hand side before you make any appreciable turn.
That's the issue; how do you lean left to start with? If the human-bicycle system has its center of gravity over the wheel line, shifting your weight relative to the bike doesn't move the center of gravity - you lean one way, the bike leans the other, and you end up in the same overall position. The only way to initiate a lean to the left is to countersteer to the right.
Some people seem to describe this difference as unconscious countersteering versus deliberate countersteering, that is, that the difference isn't really whether you're countersteering or not, but whether the countersteer is large enough that you have to do it "on purpose".
By leaning and letting the front wheel steer itself, you can turn with hands off the handlebar. When I used a bike to go to the train station, I'd often bike without touching the handlebar for parts of the ride, including the turns. Yes, I was young and stupid.
Maybe I am still young and stupid, but I cycle a lot and as often without hands on as the situation allows... It is just much more comfortable this way.
Bu yes, also more dangerous, so in difficult trafic I usually don't do it
It's true, but in all the years of my childhood when I did this (and I rode and turned no-handed often), I never once had an accident when my hands were off the handlebars. Your warning is still useful, I think, but I also think good judgment goes a long way here.
I've introduced confusion here by talking about leaning left. I should have said 'shift your weight such that the bike leans left'. See my other comment for a fuller explanation.
> It's often claimed that _all_ steering on a bike requires countersteering, but that is false.
Sounds like you've never ridden a motorcycle? It's obvious on a motorcycle that you counter-steer all the way through a turn.
If you analyze bike steering more carefully, you will also find that you're always counter-steering. But the definition of counter-steering might be different than you think.
You have to think about the front wheel's turn angle in relation to your turning radius. If you're riding in a right turn circle, then your wheel position will be turned right and not changing. In order to change that turning radius, you will always steer in the opposite direction of your desired direction relative to where your steering is at steady state.
So counter steering doesn't mean that if you are turning right your wheel is left of center. Counter steering means that to turn more right, you need to steer left of where you were. When making small adjustments, your steer might be right of center at all times even though you go from a right turn to a sharper right turn.
In other words, it's the delta of your steering angle that is always counter, not the position of your steering angle.
Does that make sense?
One easy way to understand why you're always counter-steering was given in the video: a bike is physically equivalent to an inverted pendulum. In order to move the pendulum in a given direction, you always have to move the base the other way, at all times. This is true on a bike too.
> Sounds like you've never ridden a motorcycle? It's obvious on a motorcycle that you counter-steer all the way through a turn.
Once the turn has been initiated and you are in the turn, I don't believe you continue to counter-steer.
I think instead that once in a turn you feel a force trying to continue the front wheel deeper into the turn and you must maintain a counter force to prevent that. It seems unlikely that the front wheel is actually angled out away from the turn.
> Once the turn has been initiated and you are in the turn, I don't believe you continue to counter-steer.
Sounds like you haven't ridden a motorcycle? In a hard right turn, you will need to keep constant pushing pressure on the right handle (steering left) in order to stay in the turn.
And maybe you didn't follow the rest of my comment? Counter-steering doesn't mean your wheel is left of center during a right turn. It's referring to a change in turning radius. At all times. Yes, your wheel might be turned right during the stable lean angle of a right turn (or it might not) but "counter steering" is referring to when you change your turning radius. You always steer the opposite direction that you were steering before. If you're in a right turn and want to turn sharper, you steer the wheel left of wherever it is. If you're in a right turn and want to straighten out, you steer the wheel right of wherever it is. It doesn't matter where the wheel is, all that matters is which direction the change happens.
If you're in a stable lean with a constant turning radius, then your steering isn't changing, so I guess perhaps technically you're not counter-steering, because you're not steering? This is more confusing than clarifying, and not always true anyway. It's better to realize that the "counter" in counter steering is referring to the derivative, not the absolute value. It's referring to the change in steering, not the angle the wheel is turned.
> It seems unlikely that the front wheel is actually angled out away from the turn.
You might want to google gp moto pictures before making claims, you can find tons of images of racers in the middle of the turn with the wheel angled outward. For example: https://i.ytimg.com/vi/dtCD63fKw58/maxresdefault.jpg
> In a hard right turn, you will need to keep constant pushing pressure on the right handle (steering left) in order to stay in the turn.
This is not usually true (though sometimes is at slower speeds.) Bike geometry and speed changes how this works a good bit [1][2]. Tracking my old 600cc, I'd need positive at slower speeds, but would need to steer into the turn once I had a good lean angle at anything 60mph+.
> You might want to google gp moto pictures before making claims, you can find tons of images of racers in the middle of the turn with the wheel angled outward. For example: https://i.ytimg.com/vi/dtCD63fKw58/maxresdefault.jpg
This is really uneccessarily condescending again. Also, that really looks a rider deepening lean as he rounds the apex. I'm thinking that wheel's not staying at that angle for long.
I encourage you to check the tone of your comments. Being rude to folks, especially while being wrong while doing it really brings down a community, and I hate seeing that happen on HN.
> Repeating this is so unnecessarily condescending.
I didn't mean it to be condescending, it's an honest question. People commenting don't seem to have the experience to back up their comments. I know for a fact that a hard turn on a motorcycle sometimes requires obvious counter-steering even during the stable middle of a turn, because I've done a lot of riding. I agree that bike geometry and speed changes things, but you've just validated what I said with your experience.
> I'm thinking that wheel's not staying at that angle for long.
Your assumption is incorrect, you can see it more clearly if you watch videos. The extreme counter-steer during moto races happens all the way through a turn, and then it happens in the other direction in order to end the turn. The part you and the parent comment missed is the bike forces try to un-lean when moving forward, and it becomes very apparent at higher speeds, so constant counter-steering is necessary.
> I encourage you to check the tone of your comments. Being rude to folks, especially while being wrong
I know it can be very hard to understand someone's tone, but it's equally wise to check your assumptions and your own tone. I was simply trying to make my point clear precisely because it appeared the comment above didn't understand what I said the first time.
You've claimed I'm wrong, but I don't believe I am, and I've provided evidence for my case. From my point of view, pushing back on that without evidence is rude, as is arguing against my first sentence apparently without reading the rest of the clarifying explanation.
BTW, what you didn't see is that I upvoted @JKCalhoun for engaging in the discussion.
Well, my description isn't amazing or as clear as it could be. ;) There should be a way to explain this without technical vocabulary.
How about this? If you sit still on a moving bike, and you don't try to lean, bike steering changes your lean. While you are turning your wheel further to the left, your lean to the right is increasing (your right side turning radius is decreasing).
That's it. That works for negative angles and negative lean, meaning if you're steering right and leaning right, then you start moving your wheel to the right, your left lean increases because your right lean decreases.
And it's always true. No matter where you start, you could be already turning left or right, steering more to the left always sharpens your turn to the right.
Does that make any more sense? I really do want to find a better way to describe counter steering so it becomes more intuitive and easier to understand.
Counter steer happens at all speeds at all times on a two-wheel vehicle, it's just hard to notice at slow speeds, and confusing because you do steer right during the stable lean angle portion of a right turn, as depicted in the first image in that Wikipedia article.
I think counter-steering is misunderstood since people assume it means that if you're turning right then your steering has to be left of center. But counter-steering is referring to the direction of change, the steering delta, not the absolute steering angle. You always steer in the opposite relative direction from what you'd do in a car. This is still true on a bicycle at 1mph.
I'm no physicist, but it seems the intuitive reason countersteering works is because when you turn, e.g. left, your center of mass also moves left because you need to lean left in order to turn. So if you turn left on your own this will move your center of mass left. And if you turn too sharply left your center of mass will be so far out that you will fall over. So turning right very quickly before turning left means that your center of mass suddenly shifts massively right, and therefore you get some extra time turning left while your center of mass is still busy shifting from right to left?
I used to ride a bike with no hands. I was still able to countersteer! If I leaned to the left, the bike would lean to the right, the steering wheel would go right, then I could lean to the right into the turn.
The best way I've found to experience this is to first learn to ride with no hands. This works best at speed. You actually steer by shifting your weight, but the easiest way to learn is is to grip the seat with your thighs and think about turning the bike by trying to turn the seat.
Once you can stabilize a no-hands ride, try pushing on the handlebar with one finger. You will find the the bike turns in the opposite direction of what you would naively expect. The harder you push, the tighter the turn will be in the "wrong" direction.
Not fan of the term "countersteering". If you changed the mechanical direction that the handlebars rotated the front wheel I doubt anyone would bother to call it "prosteering".
A better way to think about this is that bikes turn by banking. The method of controlling the angle of bank does not map in a simple way to the direction of turn.
> The method of controlling the angle of bank does not map in a simple way to the direction of turn.
Sure it does! (Unless by "simple" you're ruling out derivatives). If your wheel angle is moving right, then your bank angle is increasing left (or IOW, your left turn is becoming sharper, left turn radius is decreasing). While your wheel angle is moving left, your bank angle is increasing right. Whenever you stop moving the wheel, your bank angle will stop changing and you will be in a constant radius turn.
> I doubt anyone would bother to call it "prosteering".
Not sure I understand this objection... there's no rule about symmetric or consistent prefixes. Lots of things called X have a counter-X (see also anti-X). Examples: counter-intuitive, counter-insurgency, counter-strike, counter-reformation, counter-current, etc.
Counter-steering is differentiating from steering. But there's no need to differentiate normal steering from steering, so we don't normally prefix things with "pro", unless you're talking about someone who advocates for something. I think there are a few counter-examples to that in physics though. :)
In motorcycle safety, it's rather important to call out the counter-intuitiveness of counter-steering. People's reflexes tend to do the wrong thing in tight situations where quick steering is needed. If you need to turn right very quickly and haven't learned counter-steering, you can injure yourself by trying to steer right, and many people have.
It's pretty common for riders who haven't learned counter-steering to believe that leaning hard will be sufficient, and/or that body lean is as or more important than steering. But to turn very quickly, knowing about and being able to counter-steer is incredibly important.
Well the aviation people, who also control vehicles that are controlled by banking, don't bother to come up with a special name. When teaching people to fly they first teach how the controls can be used to control the attitude of the vehicle (roll, pitch, yaw are the terms that are used). Then they start a whole new discussion of how various attitudes will affect where the vehicle will end up.
Some things can't really be simplified (and perhaps shouldn't be).
Easiest way to try/prove this is ride without holding handlebars. You can turn corners easily.
Limits (compared to regular turning) are your lowest speed is higher (where you'd lose balance without holding handlebars) and the fact your center of gravity and stability are messed up (can't turn as tightly). And self preservation of course.
I've done a lot of riding without holding handlebars, so that's how I learned this.
Another limits is that you've got a delay to reach the brakes, which can make it dangerous for others in addition to yourself. And I agree that having your center of gravity moved up really mess up your stability.
Only if you've got a stupid racing bike with only hand brakes. Coaster/foot/back-pedal brakes are standard issue around these parts, and I wouldn't ever want to ride a bike without one.
Depends on how you ride. An adult in the US, you're on a road bike bent over the bars and going 15-20mph. Hands on the brakes at all times. I do a ride every summer with 20,000 like-minded people and if you see even one bike with coaster brakes all week its unusual.
Brakes on rear wheels only are relatively ineffective, so I don't understand why you would prefer them. Unless there is such a thing as a front wheel pedal brake, which I have never heard of.
Rim brakes either grip too hard or not enough, and sometimes don't work very well in rain, and need regular maintenance and replacement. Coaster brake supplemented by hand brakes for emergency stops just feels safer and more in control in traffic situations.
It's very easy to try. Go up to speed (20 km/h or so) and press on a handlebar, away from you. You will "turn" to that side even though the handlebars are moving in the opposite direction.
Here's how I explained countersteering to myself: To turn left, I need to lean left. The easiest way to lean left is to pull the bottom of the bike, where the wheels touch the ground, to the right.
