"...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:
http://bicycle.tudelft.nl/schwab/Bicycle/DO-07-3-2bicycles.p...
"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."
http://socrates.berkeley.edu/%7Efajans/Teaching/bicycles.htm...
with plots of torque-vs-time and analysis here:
http://socrates.berkeley.edu/~fajans/pub/pdffiles/SteerBikeA...
The author spends most of his time at CERN, but got interested in bike physics for a couple of years.
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?
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.
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.
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.
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.
https://www.youtube.com/watch?v=HOGQ-HePrT8
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.
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.
http://www.sheldonbrown.com/headsets.html#troubleshooting
(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.
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?
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.
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.
