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Old 06-06-2006, 08:00 PM
Red Barchetta Red Barchetta is offline
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Motorcyclists: Explain Counter-Steering to Me

I’ve recently developed an interest in learning how to ride a motorcycle, so as practice, my father took me out on his freeway-capable scooter (don’t laugh) to get used to the handling. As this is strictly practice, I’ve only been able to drive around in a parking lot at a top speed of 25 mph. With that said, I didn’t seem to have any trouble steering or cornering (granted, I’m not doing insanely tight turns, but I’d say they’re pretty concise).

Anyways, after a few practice runs I did some research on the internet regarding motorcycles, and it seems that “counter-steering” is an integral component to actually steering a motorcycle. “Push left to go left, push right to go right.” Consider my mind blown.

Upon reflection, I don’t recall consciously ever having to “counter-steer” in order to initiate or complete any of the turns I did while practicing. But according to everything I read, I must be counter-steering, lest I would essentially be going nowhere fast. So what’s going on? I have a few questions pertaining to this:

1) Does riding a scooter impact the need for counter-steering at all?
2) Am I perhaps already sub-consciously counter-steering?
3) Do I have to be going faster than 25 mph in order for counter-steering to be a requirement?
4) Does riding a bicycle require counter-steering as well? If so, it seems odd that such a basic technique would seem to have so much attention placed upon it, at least based on what I’ve seen.

Please enlighten this ignorant fool. FYI, I am taking a safety course later this month, but I figure the sooner I learn the basics, the better off I’ll be. Thanks!
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  #2  
Old 06-06-2006, 08:23 PM
Mr. Goob Mr. Goob is offline
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You are already doing it and don't realize it. I rode for years before I ever heard of the term.

Think of the cross section of a tire. If you lean to one side there is less circumference of the tire against the road and the bike will turn to that side.

Go in a straight line a weave from side to side to picture what I mean. When going around a bigger curve you can't just lean, you push the bars to one side or the other. It's pretty instinctive.
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Old 06-06-2006, 08:45 PM
cornflakes cornflakes is offline
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As Mr. Goob said, cycles turn when you lean them into a corner, and the fastest way to lean a bike over is to turn briefly to the outside of the turn.

With their small wheels and guick geometry, scooters turn quickly. Compared to motorcycles they could be described as "twitchy." It doesn't take much countersteer to lean a scooter over in a turn.
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Old 06-06-2006, 08:56 PM
Johnny L.A. Johnny L.A. is offline
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Quote:
Originally Posted by Red Barchetta
4) Does riding a bicycle require counter-steering as well? If so, it seems odd that such a basic technique would seem to have so much attention placed upon it, at least based on what I’ve seen.
You do exactly the same thing on a bicycle. Why is so much emphasis placed on motorcycles? Complete guess off the top of my head: People are used to driving cars and turning left to go left and right to go right. Maybe people want to make sure that they don't try that on a motorcycle at speed? (Incidentally, my first ride on a JetSki was interesting, since they have motorcyle handlbars, but you steer them like a car.)

Why do you countersteer? As a helicopter pilot I put it down to gyroscopic precession. (A force on a rotating mass manifests itself 90º later in the direction of rotation. i.e., pushing on the right handlebar pushes right on the rear of the gyroscope -- the wheel -- and the tilt imparted manifests itself as a right force on the top of the gyroscope causing a right bank resulting in a right turn.) Only IIRC someone on the Dope said that that was completely wrong. So until someone answers it again, I don't know.
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  #5  
Old 06-06-2006, 08:59 PM
Danalan Danalan is offline
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The front wheel, at surprisingly low speeds, is a gyroscope. When you move the gyroscope off axis, it pushes back. Turning the wheel to the left causes the bike to lean to the right. Since the tires are rounded, this reduces the turning radius on the right side of the bike vs. the left side, so the bike turns right. It's counter-intuitive.

In an advanced turn, you actually have to turn the wheel toward the direction you're turning to keep from falling over, and sharply turning in that direction is how you end the turn.
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  #6  
Old 06-06-2006, 09:39 PM
commasense commasense is offline
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Motorcycle rider for 30 years here.

For ordinary turns, lean into the turn and look where you want to put the bike. It'll go there. Don't think about "push left to turn left," it won't help.

The only conceivable use for "push left to turn left" is if you have to avoid a relatively small obstacle very suddenly. And even then, I'd recommend it only if you practice it in advance.

The thing is, the gyroscopic force of the front wheel does not allow you to steer a motorcycle (or bicycle, either) in the way one might naively assume, i.e., to go left, pulling the left handlebar back toward you to angle the wheel to the left. It won't work. Paradoxically, that move will turn the wheel to the right.

Try it (carefully) the next time you're riding: at a moderate speed, 30 or 40, push the left handlebar forward a little. The wheel will turn to the left.

However, something as massive as a motorcycle wheel will right itself back to its original path very quickly. It might allow you to avoid a thumbtack on the road in front of you, but to swerve out of the way of something more massive would require some serious body English in addition to whatever you do to the handlebars. So "push left to turn left" technique is of limited use in real world motorcycling. At least, that was my experience. I practiced it many times, but never used it in a real-world emergency.

As others have said, your smaller scooter wheels will be twitchier.

I think the "push left to turn left" advice arose to counter the naive expectation that in an emergency, you should pull left to turn left. However, just saying "push left to turn left" is hardly sufficient to explain an advanced technique and the circumstances in which it might be useful. In an emergency, you don't have time to think, "Was it push or pull?" You have to react by instinct. If you want to learn accident avoidance techniques, take an advanced class, or do some reading and practice in a safe, controlled location, preferably with professional, or at least more experienced, assistance.

Or you can do what most of us do: learn what works and what doesn't through hard experience over many years. If you're lucky, you won't break too many bones. (I only broke one: my collarbone.)

In short, don't worry about it. Go to your motorcycle course, learn as much as you can, read as much as you can. And get out and ride.
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  #7  
Old 06-06-2006, 10:32 PM
scr4 scr4 is online now
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Think of it as a way to purposely disrupt your balance. By steering to the left, you quickly "fall" to the right side. In mid-fall you re-establish your balance, except now you're at an angle and moving in a curve towards the right, and you are achieving balance with the help of centrifugal force.
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Old 06-06-2006, 10:56 PM
outlierrn outlierrn is offline
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Quote:
Originally Posted by scr4
Think of it as a way to purposely disrupt your balance. By steering to the left, you quickly "fall" to the right side. In mid-fall you re-establish your balance, except now you're at an angle and moving in a curve towards the right, and you are achieving balance with the help of centrifugal force.

I agree with this, I'm not arguing the gyroscopic effect, but I think the balance is the key factor. I will argue with commasense though, I counter steer through fast sweepers all the time, and I've been doing it a long while, it's one of the most fun things you can do on a bike. If you try to steer right, centrifigal force will try to pitch you forward, which has become the left of the bike. Because you're up high you're unstable. If you countersteer left, you drop into the right and your weight is down through the machine into the tires. You control the turn with your body position and the throttle; all other things being equal you only imput the handlebars once, at the start of the turn. IMHO this is less obvious at low speeds, and on bicycles. Have fun, as an ER nurse I recommend full face helmets.
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  #9  
Old 06-06-2006, 11:01 PM
Johnny L.A. Johnny L.A. is offline
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No, not 'think'. Do!

Seriously, it's good to know that you need to countersteer; but as has been pointed out, it's not something you can take the time to think about in an emergency. When you're just cruising you don't have to think about it because you do it subconsciously. If you need to react quickly you need to rely on your reflexes -- which should be automatic after riding experience. (I started riding when I was five -- longer than commasense -- and as I graduated from minibikes to proper motorcycles I found that all that dirt riding served me well on the street.)
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  #10  
Old 06-07-2006, 03:48 AM
Schuyler Schuyler is offline
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Push left to go left is used to remind riders that the fastest way to initiate a left turn, for accident avoidance or whatever, is to steer the front wheel right which causes the line of the tires to steer out from under the c.g. of the bike - now the bike wants to fall over left, which is just what is needed to execute a left turn. The same thing can be achieved by shifting body weight alone - if it couldn't, then no-hands bike riding wouldn't work - but it's slower.

As far as gyroscopic effect - this is not needed to stabilize the motorcycle and make it rideable. Bicycles and motorcycles at low speeds have little rotational momentum, and it's the front wheel trail that is the biggest contributor to stability. In fact, zero-gyroscopic bicycles have been built and ridden. A couple of nice internet references:

From Ansers.com:
Quote:
That gyroscopic effects are unimportant at normal cycling speeds was shown by physicist and researcher into bicycle stability David E. H. Jones, whose series of "URBs" ("unrideable bikes" with various modifications to the front end) included a bike which cancelled the gyroscopic effect of the front wheel by dint of attaching a second wheel to his front forks (alongside the regular wheel) whose lower edge was about an inch (25 mm) above the ground. By gearing this wheel to the regular front wheel so that it spun in the opposite direction at equal speed, the net angular momentum of both wheels together was close to zero. Jones found he could ride this bike with no difficulty, but did discover that without a rider the non-gyroscopic bike fell over much faster than a regular bike.
From Motorcycle Stability and Steering by Andy Townsend:
Quote:
If we intentionally move the contact patch line from vertically beneath the Center of Gravity, the bike will start to lean. For example, if while riding the bike straight ahead, we press on the left bar the front wheel points to the right. The front wheel tracks to the right (sometimes called “out tracking”). So the weight of bike and rider is now to the LEFT of it’s “support” on the ground, the tire contact patches. Because the weight is to the left, the bike leans to the left. It is important to note, for a LEFT turn, we initiate a lean to the left by pressing on the left bar, turning the front wheel to the RIGHT. This is often referred to as COUNTERSTEERING: a turn to the left initiated by turning the front wheel to the right.

The harder you press the quicker the lean; the longer you press, the further the lean angle.
And finally, I did read something in (I think) a recent issue of Cycle World, where a guy was going to build a reduced-gyroscopic-effect motorcycle, on the reasoning that it would respond quicker to rider inputs for steering transitions.
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  #11  
Old 06-07-2006, 03:53 AM
Schuyler Schuyler is offline
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To echo Johnny L.A., this should all be unconscious by the time a person has any significant riding time. It's not even an issue on a bicycle. Since the steering is so fast and the machine is so light - if you actually "pushed" on the bars, you'd probably go right over!
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  #12  
Old 06-07-2006, 06:47 AM
Malacandra Malacandra is offline
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Also a motorcyclist of >25 years' standing. It was a couple of years before I heard about countersteering and I soon established that a light touch on the bars will tip the machine into the turn much more easily and controllably than shifting my weight to lean it.
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  #13  
Old 06-07-2006, 07:43 AM
Pedro Pedro is offline
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Counter steering is just how you lean the bike to get it to start turning. You can do that by shifting your weight only (toward the direction you want to lean into), although it's a very inefficient technique by itself because a motorcycle in a straight line at moderate/high speeds is a very stable system, mainly but not only due to the conservation of angular momentum of the rear tire.

Counter steering can be a misleading term. It has become a huge mantra but, whether you understand counter steering or not, everyone does it and practice trumps all.

There are three variables to any turn, radius, speed and lean angle. You're free to choose any two out of three. The third is set by that choice. Once you're set on a turn, with constant radius/speed/lean, your tire is pointing (very slightly) to the inside of the turn ("direct steering").

These angles are very small (10º degrees has a big effect on steering) and you can't analyse them properly without modelling the tires and the contact patch.

The main point is this: if you're in a turn and want to stand the bike up you turn the steering more to the inside and it will straighten up. If you want to lean more into the corner, you turn the steering less into the inside of the turn (that is, toward the outside) and it will turn sharper. Otherwise you leave it alone.

This only applies above a certain speed, typically given as about 20mph.
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  #14  
Old 06-07-2006, 08:22 AM
Pedro Pedro is offline
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Quote:
Originally Posted by Pedro
Counter steering is just how you lean the bike to get it to start turning. You can do that by shifting your weight only (toward the direction you want to lean into), although it's a very inefficient technique by itself because a motorcycle in a straight line at moderate/high speeds is a very stable system, mainly but not only due to the conservation of angular momentum of the rear tire.
I need to correct myself here. Where it says "shifting your weight" it should read read shifting your center of mass (maintaining the position of the bike's center of mass - and for that you need a steering input anyway) and thus moving the center of mass of the bike plus rider system, destabilizing it and getting it to lean. Then you need to correct for it again, otherwise you will fall. Just pushing more on a foot peg won't do. The bike itself may lean if you do that but it won't turn. You need an external force to the system to move its center of mass.

This was just to show that countersteering's goal is to provoke a controlled fall of the bike plus rider center of mass. The proper way to do that is using the steering.
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  #15  
Old 06-07-2006, 08:36 AM
Uncommon Sense Uncommon Sense is offline
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Quote:
Originally Posted by Pedro
This only applies above a certain speed, typically given as about 20mph.
Exactly, I read this thread before I left for work this morning and then spent the 40 minute ride into work testing different things. 20 mile per hour was about the speed I came up with when the you stop using actual conventional steering to steer the bike (nothing fancy, just start out from a stop swerving the bike back and forth while you accelerate and at about 20 mph you will not be able to steer the bike anymore by turning, you will now need to countersteer, or push).
This is why lots of people have a hard time with low speed manuevers. You reach a piont in some manuevers in which you cross the magical 20mph boundary and things change suddenly, whether you're accelerating into a manuever or deccelerating.

Some other things I tried going about 40 (on a country road - to avoid the 'looks');
Leaning to the right/left without applying any pressure to the handlebars makes the bike drift right/left.
Pushing the bars right/left while keeping the body perpendicular to the road makes the bike drift right/left.
Leaning AND pushing makes me drive through the ditch.
Just kidding, leaning and pushing will get the bike to drift much more aggressively. Use this technique in tight corners or in emergency situations where 'throwing' your body into the turn and pushing on the bars will keep you from harm or keep you on the road. Not for beginners. Most people get by with just sllightly pushing or leaning or a light combo of both. It takes some practice to feel confident with an aggressive lean and push turn. You will see this technique on the race track.

Something to think about. Try to picture driving a bike that has the front wheel locked in a 10 degree turn. If you try to ride this bike (remember, you can't steer it, the wheel is locked) you will begin out by doing circles. And below a certain speed you will be able to maintain this circle pattern, however, above a certain speed, you will start to feel the effects of the centrifugal forces. These forces will cause your body and the bike to start straightening up and eventually falling to the outside of the circle, loosing control of the bike and crashing. Now, if the wheel became unlocked as you began to get unstable you could steer out of it.
This is what's happening when you ride a motorcycle and you have to countersteer to actually cause the bike to go the other way.
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Old 06-07-2006, 11:28 AM
CookingWithGas CookingWithGas is offline
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Quote:
Originally Posted by Johnny L.A.
Why do you countersteer? As a helicopter pilot I put it down to gyroscopic precession. . . .Only IIRC someone on the Dope said that that was completely wrong.
There certainly is precession. Anyone who doesn't believe it can take a bicycle wheel, hold the axle and have a friend spin the wheel, then turn it one direction and watch it lean the other as it pulls against your hands. Although this effect may not be a significant force on a rolling bicyclist, it is very easy to demonstrate with a disembodied wheel at relatively low RPMs.

I looked up the thread you mentioned including your citation, and I'll admit it gave me pause. However, the poster scotth was making broad claims ("This is an extremely common misconception even of writers of magazine about motorcycles") but neither giving cites nor providing his own qualifications. The article you cited is interesting and may be entirely correct, although we don't see the qualifications of James R. Davis to write such an article and there is no further citation in the article.

That said, I must add that I have ridden machines like JetSkis and have noticed that they I was surprised to find that they can be countersteered in the total absence of a rotating wheel, so perhaps geometry does play a large role.
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Old 06-07-2006, 01:24 PM
scr4 scr4 is online now
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In case it's still not clear...

A body in motion tends to stay in motion, at the same speed and in the same direction. That's true for a motorcycle+rider. When you turn the handlebar to the right, the front wheel starts moving to the right, but the bulk of the mass still wants to go in a straight line. The end result is that the wheels move off to the right from under you. The center of mass is no longer above the wheels, so the bike+rider starts to fall to the left. That's the whole purpose of counter-steering.
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Old 06-07-2006, 05:45 PM
Kevbo Kevbo is offline
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Quote:
Originally Posted by Johnny L.A.
You do exactly the same thing on a bicycle. Why is so much emphasis placed on motorcycles?
A bicyclist makes up more than 80% of the total man+machine mass. So it is pretty easy to linitiate a turn by weight shifting. In fact it is very easy to ride without touching the bars at all. With a lot of experience on a bicycle, you don't think about it all. Some riders steer mostly by weight shifting, and some mostly by countersteering...and few of them think about which they are doing.

A motorcyclist makes up 30% or less of the total man+machine mass. It is difficult to steer a small dirt bike with weight shifting alone. It is nearly impossible to steer a heavy street bike by weight shifting. The grand prix racers you see hanging off the inside of the bike are doing so to keep thier foot pegs off the pavement, and keep thier tires contacting the pavement in a more favorable way.


Many new rider's will have developed a bicycle appropriate habit of steering by weight shift. These riders tend to have an early crash due to running wide in a turn, because "it just wouldn't turn". These are typically at reasonable speed for the turn involved.

By countersteering, anyone can cause a motorcycle to turn up to and beyond the limits of traction. If "the bike won't turn" it is because you are attempting to cause it to lean by shifting your body weight.

Because few bicycle riders can tell you exactly how they make a turn, emphasisiing countersteering to all new motorcyclists makes sure at least when they have that first crash because "it wouldn't turn" they might have a clue that the machine was not the root of the problem.
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Old 06-08-2006, 11:40 PM
Pedro Pedro is offline
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Quote:
Originally Posted by CookingWithGas
That said, I must add that I have ridden machines like JetSkis and have noticed that they I was surprised to find that they can be countersteered in the total absence of a rotating wheel, so perhaps geometry does play a large role.
It's the same principle at work. Turning the steering to the left generates a moment that leans the jet ski to the right. Then you must compensate for this. The force of the leaned hull against the water is analogous to the friction force on the tires. It has a normal component and a tangential one pointing inside that makes it turn. Although here the thrust from the jet probably plays a part too.

The same could be said, for instance, for a ski bicycle (single track bicycle with skis for wheels).
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Old 06-08-2006, 11:56 PM
Pedro Pedro is offline
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Quote:
Originally Posted by Pedro
Although here the thrust from the jet probably plays a part too.
Come to think of it, to take the analogy further, it's kind of like sliding the rear wheel.
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  #21  
Old 06-09-2006, 02:46 AM
GusNSpot GusNSpot is offline
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A couple of things to try or to think about.

After you have ridden a while, you may find that traffic or some idiot in a cage had crowed you into a curb so that you are running about 30 MPH with your tires rubbing the curb. This is a very difficult thing to get out of without a crash as you cannot counter steer as the curb is there and you might be already actually having your weight too far over. You will need to lean aggressively and quickly because you can't turn the front tire away from the curb as that will lean the bike even more 'over' in the curb direction. You have to use weight shift alone if you can't get stopped before you 'high side'. The front wheel ( handle bars ) must be left alone and you need to hang off the 'road' side fast and if that idiot in a cage still there, it can get even more dicey. Once against the curb, you cannot use the bike to get the center of mass back where it belongs.

Second. With practice you can dodge a skunk in the road without you actually moving your upper body much in a lateral direction.

If you do this where you can go back and look at the tracks you make, you will get a real good understanding of why M/C's steer like they do.

Tracking straight at a 6" manhole for instance, you can flick the bike to, say the right, by starting an aggressive turn to the right. You will 'push left, or pull right' , which ever way you like to think of it and the wheels of the M/C will move to the right of a straight track and the bike will start to lean but as you feed in a bit more counter steer, the bike is still traveling in a more or less straight line, actually moving out from under you to the right, let it do so. By this time you are actually past the manhole cover and with counter steer in th eother direction you stand the bike back up. Your wheels will have missed the manhole cover and your bike will have moved right and then left without actually making much or any real turn.

It is just a fast way of going down a street and leaning the bike over one way but shifting your weight the other so that the M/C is leaning at some angle with you holding some counter steer in and using you weight to force the M/C to travel straight by using your weight to keep the center of mass over that part of the tire pactch that allows it to go in a straight line even though you are a bit to the side of the center of the tire.

The real informative part is when you go back and look at the tracks.

Always remember to look where you want the bike to go and not at what you want to miss.

YMMV
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