"...the phenomenon of 'countersteering', whereby the rider can steer to the left only by first briefly torquing the handlebars to the right, allowing the bike to fall into a leftward lean."
Am I just doing this subconsciously?
This PDF explains it very well, with illustrations, on the last page:
"Practically nobody is conscious of the fact that they must steer briefly to the left ion order to make a
right-hand turn. But this is not so strange, because the swerve is very small (approximately 3 degrees)
and happens very quickly – 0.5 seconds. The wet tire tracks from cycling experiments reveal that we all
do this. Apparently we learn this unconsciously when we learn to ride a bike."
with plots of torque-vs-time and analysis here:
The author spends most of his time at CERN, but got interested in bike physics for a couple of years.
Let's say you want to turn left. We know from experience that you will be leaning left when you turn: meaning, your weight is going to be on the left hand side of your wheels. (The common-sense explanation works really well because I'm not going to explain why you need to lean left to steer left, I'm just going to take it as a given.)
The basic-physics question is: if you're starting totally vertical, how the heck do you get your body mass to be on the left hand side of the wheels in the first place?
You can get a little bit of effect, of course, by simply leaning over left: but that leans the bicycle to the right because you can only lean over one way by pushing your bicycle the other way... and when you do this the bicycle briefly opposes you in the way it's leaning before your gravity can win out. That's less good.
So what your brain has actually learned to reflexively do is, to send your wheels going off to the right while your body continues in a straight line, hence your mass is now over the left-hand side of your bicycle and there is no competition. You then steer into the turn and complete it normally.
I can steer pretty well without hands. It seems as if I must be able to initiate the left lean without pushing the handlebars right.
So why couldn't I also do this when not riding without hands?
Pay attention to yourself next time you ride and you might be surprised.
The momentum from the flick your body creates begins to turn the wheel a small amount, and the forward momentum of the bike in combination with the lean keeps the wheel turned right. By contrast, if you flicked the bike/wheel but did not lean, the wheel would simply straighten itself again.
Even for automobiles this stuff is very simple suspension + steering mechanics. Due to how their suspension & steering components are designed, and assuming they are aligned properly, a car will always follow the road. If the road leans + curves, so does their steering.
Fun fact: when I read about it I had to test and I had to make sure I wasn't deceiving myself so I put one palm in front of the handle on one side and the other one behind the handle on the other side. That way I could ensure I pushed it the correct way.
It worked exactly as advertised (50cc bike so somewhere below 60km/h).
Much simpler than using slow motion camera etc.
Thinking about it though, I think I did countersteer in order to drop into bowls while riding vert BMX.
Edit: I should mention in mountain biking you are frequently dealing with a low traction environment, which I think has a large impact on the techniques.
But yeah, hypothetically lower inertia = more ability to steer with weight, obviously.
Try it. Get on a bike. Go straight, and pick up speed. Intentionally press the right side of the handlebar. Note which direction the bike is now aiming.
The way I describe it is that the wheels MUST be underneath the force exerted by the center of mass. In straight-line riding, this means your wheels are under you. In a corner, your mass is to the "inside" of the corner, but the centripetal force added to gravity's downward force ends up pushing down to where the wheels are.
So you need to steer a bicycle so that the wheels are always under this center of mass force (I'm sure there's a word for it).
Hence, if you were to turn the wheels in the direction you wanted to turn, you'd fall over, off the bike, to the outside of your intended turn.
Therefore, to initiate a turn, you have to steer the wheels out from under the bike (the "wrong" way) to initiate your mass's 'fall' into the corner. Then you steer the wheels back under you to balance the fall.
Most riders don't really think about the torque they're applying to the handlebars, but when you lean into a turn you're definitely applying that torque to the handlebars. You're kind of putting the side of the wheel to the ground in the process, and the only way to put the side you want to turn to towards the ground is to torque the handlebars in the opposite direction.
Perhaps because the rake is so much greater, it's not a natural, immediate carryover from bicycles. Or perhaps because the motorcycle is much heavier, handlebar input becomes all the more important, relative to a bicycle you can steer with your body.
I was taught that 2 hours into my training when I prepared for the exam to get my license. I remember my instructor telling me to ride in straight lines and try to gently push the handlebar to the left or right and "see what happens." Then he would make me try the slalom part of the exam.
I sometimes let go of the handlebar (when decelerating and when there's no traffic around me) and it takes a lot more effort to make minor adjustments to the trajectory by shifting my weight only.
Prior to that you turn the bar into the direction you want to go, above that you do the opposite. The cerebellum rules.
When riding a motorcycle it's very noticeable. Just tipping the handlebar with the finger at 100km/h and it will lean into the other direction.
When you are riding straight you are using a combination of balance and handlebar position to adjust the angle of the bike so it is directly between you and the ground. If you fail to do this you fall over. So to turn without countersteer just stop doing anything and start to fall over. When you reach your desired angle of bank then turn the handlebars in the direction you are falling just enough so the acceleration from turning exactly counteracts the force that is causing you to fall. You are now in a continuous turn and you didn't countersteer at all.
If you don't want to have to wait to fall or want to turn in a particular direction you will end up turning the handlebars in the opposite direction for a time. But that is just you continuing to adjust the angle of the bike to a desired angle like you do continuously all the time you are riding the bike. You haven't done anything different or counter intuitive. I personally don't consider "countersteer" to be a thing.
It sounds like you've never ridden a motorcycle? Most safety courses on motorcycles teach counter-steering, precisely because it is a thing and failure to understand it can compromise your ability to recover from a bad situation.
On a motorcycle going fast, you counter-steer continuously. If you make a slow right turn on a freeway, you can turn for 30 seconds by only pushing forward on the right handle.
I'm pretty sure you always counter-steer even on a bike, it's just very hard to notice, especially going slow. We don't think about it. It's not really a choice though, there's only one way to turn without leaning, you don't get to pick counter-steering or not.
You should definitely try it on a bicycle while going fast. Once you consciously turn your handlebars right and end up steering right no matter what you do, it becomes really clear.
Pushing on the side of the handlebar on the direction I'm turning counters this desire of the bike to fall into the turn. That's counter-steering. It's a pretty unconscious action, and to most feels like what comes natural when one leans a bike to turn.
I generated an argument that refutes that statement in the post you are responding to. I am not arguing that the effect does not exist, only that it isn't interesting and is not worthy of a special term to describe it.
FWIW I ride motorcycles on a regular basis... I oppose the discussion on countersteering in the regular motorcycle training curriculum because it suggests that there is more than one type of turn for no real reason. It would be better just to say that you turn on a motorcycle by changing the angle of the motorcycle from vertical. Then there is only one thing to learn.
That's why you're always counter-steering on a two-wheeled vehicle; because turning the handlebars right of where they currently are always causes you to turn more right of where you'd have gone if you didn't move the handlebars.
Since you ride motorcycles, then you already know anyone who's facing a quick turn definitely does not want to wait to fall. To turn quickly, you must counter-steer.
I am curious why you think it's not worth a special term, when it's unintuitively opposite from the way car steering works, and it's important to know in order to stay safe?
I disagree with that. Before someone learns to turn a cycle, motorized or not, they have to learn to not fall over. So we tell them that they have to turn towards the direction they are falling. Once they master not falling then in practice there is nothing more to teach. They can easily generalize to adjusting the bike to any lean angle because the required motion of the handlebars is exactly the same. If we don't tell them about countersteering they will have no idea they are doing something different for steep turns vs shallow turns. They just have to establish a greater angle sometimes.
Back in the day prospective pilots were taught by having someone show them how to move the controls for each possible manoeuvre. These days the prospective pilot is first taught what the effects of the controls are. After that they are entirely responsible for achieving the required aircraft attitude using that knowledge. They are told to roll the aircraft to turn. They are not told that they have move the stick to the right for a while and then centre it even though that is something that would not produce a continuous turn in a car.
"28. Motorcycle riders in these accidents showed significant collision avoidance problems. Most riders would overbrake and skid the rear wheel, and underbrake the front wheel greatly reducing collision avoidance deceleration. The ability to countersteer and swerve was essentially absent."
Wikipedia's article on counter-steering with respect to motorcycle safety begins with:
"Even more so than on a bicycle, deliberately countersteering is essential for safe motorcycle riding"
You're free to argue against it using logic and analogies to pilot training, but both safety data and public opinion don't seem to agree. I would counter that pilots are most definitely taught that pushing forward (up) on the yoke causes the plane to dive (go down), that is somewhat analogous to counter-steering. They are also taught that turning left causes a left roll.
But this didn't answer my question either - counter-steering is so-called because you steer counter to the direction of turn, which is true. Even if it weren't a safety issue, why would it be inappropriate to name it? It is a thing that's different in some ways from other types of steering; we should have a name for that. We have names for everything.
No, they are taught that pushing forward on the yoke causes the nose of the plane to pitch towards their feet. The result of that depends on the starting attitude of the aircraft. Think inverted flight as an extreme example. In exactly the same way, pushing on the right handlebar has results entirely dependent on the starting attitude of the bike.
Your comment about the roll is correct. That is an effect of a control.
I am pretty sure that I have answered your question. It's just a pointless distinction to make. Such pointlessness detracts from actual important lessons. Should we come up with a name for the "oversteering" used to recover from a turn (pro-steering?)? After all, if you don't do it you will be stuck in the turn forever. That would be dangerous.
Ignoring the reductio ad absurdum, then if you're referring to how you have to steer the handlebars further into a turn in order to straighten out, there is a name for that: counter-steering. :)
Because motorcycles are so massive (at least mine is), body steering is much less effective, but it does help if you want to lean the bike a bit further. That's sort of where the advice to "push down with your legs comes from", since it shifts the bike down as you push yourself up - voila, bike wheels make a deeper u shape, capsizes a bit more, and turns harder. It's a trim knob for turning, kind of how the rear brakes add stability while the front do most of the work.
Like a lot of the points in the MSF course, it's a useful detail to internalize so that when something inevitably dumb/awful happens on the road a poorly trained snap decision doesn't lead to panic (ohgodohgodohgodthebikeisntswervingfastenoug-), but in everyday life you won't be thinking about it directly.
Better than teaching students, "push right, go right. Push left, go left"? Yeah, I'm thinking your way isn't better. Your way, as I read it, just reinforces the idea of "you turn a single track vehicle by leaning". That might have some technical correctness, but it's practically worthless information as far telling a rider what they physically need to do.
Makes for great arguments on the Internet, though, and I'll bet if I cruised over to rec.moto it is still going on some twenty-five, thirty years later after it first started.
Countersteer is the only way to turn a bicycle at speed. If you lean, you are simply inducing the bike to countersteer for you. The fact that you are not conscious of this act does not change the fact that it is happening regardless of your awareness.
More to the point, you cannot turn a bicycle at speed to the right by turning the handlebars to the right. The bicycle will go left, independent of your intentions.
If you are on a moving bike and you turn the handlebars to the right you will soon be on the ground. :) On a two wheeled vehicle the handlebars are used to adjust the angle of the bike/rider system with respect to the ground. The handlebars are not used for turning but for adjusting things so that a turn can occur. "Countersteering" is something that occurs at all times and in all situations. It has nothing special to do with turning.
Many people that ride bikes never know about counter-steering, unless they ride motorcycles too. So, you're not alone. I didn't know about it on a bike until I learned riding motorcycles.
EDIT: There's a neat heuristic that was brought up in the course: the center of mass of the bike is above the bottom of the wheels, and a turning bike must lean into the turn (weird road geometries excepted), therefore to turn the stuff under the center of mass must counter the top leaning in. Thus to go left, you push left, causing the front wheel to pull out from under the bike right-wards, which starts to capsize the bike leftwards! Like I said before, a bicycle reacts really really hard to this, but a hefty motorcyle has a far lower center of mass and leans into it more gracefully.
Well yes, seeing as that's how you steer a bicycle. As a keen cyclist it annoys me when people (especially coaches) start harping on about countersteering being an additional technique you should learn, when it's what everyone has been doing intuitively since they first learned to ride a bike.
Counter-steering is said to be important to learn consciously because it's unintuitive, and people have crashed and died on motorcycles in panic situations by turning their handlebars toward their escape route only to have the bike go the opposite direction. Or at least I heard a rumor about that in my MSF course.
I do think it's valuable to know this fact consciously and not rely on body intuition, but I'm also sure it's much more important for motorcycling than for bicycling.
I know this works for sure on a motorcycle, and I've tried this experiment on a bicycle too, you can turn a bike right just by pushing the handlebar forward with your right hand. Totally counter intuitive but it works and I'm pretty sure we do it subconsciously when we lean by pushing on the handlebar and we end up counter-steering.
It's an example of a skill most of us acquired and use every day all without being accessible to our conscious brain.
In fact, not only is it unconscious, most people consider it very counterintuitive.
What other types of cognition do our bodies perform everyday that we aren't aware of? I'd argue that the amount of cognition accessible to our conscious mind is only a small fraction.
"To turn left you need to lean to the left. Leaning to the left momentarily forces the handlebars to turn the right."
This describes an equivalent outcome to the quotation from the article but implication about what is cause and what is effect is quite different.
The countersteering argument has been repeated literally 100's of times on the internet on motorcycle forums. It's not worth debating as it is absolutely a real phenomena. It's counterintuitive yes, but there is no doubt that it is real.
For cycling, I can only explain this passage by saying I lean a little left first, possibly providing that right torque, which then enables the handlebars to turn fully left into the turn.
But I have no idea what I'm talking about.
My master touched this. Used AI to find spoke patterns. http://master.matsemann.com
> There were untested geometries out there that could transform bike design.
Better hardware and simulations makes it easier to test thousands of these, possibly with the help of AI. I wonder if any drastically new designs will be found in the feature, or if time will show the current design is the best.
But for my colleague - he finds it much easier to balance his racing bike.
As the article suggest - the hope is that this will provide better guidelines for building bikes that are more stable.
The balance on my mountain bike definitely saved me from two near crashes of a knock to my rear wheel by a u-turning car and being hit on the handle bars by a wing mirror.
(see section on "Indexed Steering")
(From today's stage of the Tour de France)
This is all coupled by the fact that the rider is actively piloting and adjusting the bike to keep it under control at all times. The bike seems like it would balance to me because the control mechanisms are designed to keep things balanced easily.
Second most embarassing thing the bike ever did to me.
And nitpick: typical bicycles aren't symmetric left-right. The chain and gears make them heavier at the right. Most mass is close to the center line, though, so its moment is negligible, especially when ridden by a human.
You can steer by either turning the basketball (horizontal plane) or leaning the basketball (vertical plane). In the case of a motorcycle at speed, the bike's effective turning radius is affected more by the lean than by how much the handle-bars are turned. The handle-bars are more about controlling the amount lean.
If you know more than the rest of us, it would be good to post an informative comment that teaches the reader something. If you don't want to do that, it's fine to post nothing.
I was clearly wrong in that many people disagreed and found this to be an interesting and nontrivial subject.
Bend left -> torque to the right, bend right -> torque to the left. Here you have the basic ingredient for stability: the one torqueless angle is the bike going straight perfectly vertical wrt the ground, while any perturbation leads to a torque in the opposite direction.
I felt it was basic stuff maybe it's not?