Countersteering?

[Agemax]

all you need to know.......

http://en.wikipedia.org/wiki/Counter_steering

 

[Sandy]

Do any of you know at what speed counter steer begins to work??? Does it begin at the same speed on all 2 wheeled vehicles??? It seems to be about 18 or 19 mph on most motorcycles. Kids learning to ride bicycles won't experience counter steer, because they probably won't go fast enough for counter steer to be used. I've always wondered exactly where it starts.

Try walking a bicycle down the driveway with it perfectly balanced upright and holding the bars very lightly with 2 fingers and turn the bars slightly left. What happens? When I do it, it sure wants to fall to the right. What countersteering actually does is momentarliy put the motorcycle off balance by moving the wheels out from under it's line of travel. This is what induces a turn in the opposite direction, not gyroscopic effect of the wheels or other such things. Gyroscopic effect may make it easier or harder depending on the setup but if you had a way of moving the tires out from under the bike in one direction at 0 mph, the bike would naturally fall the other way.

 

[Counter]

Steering a motorcycle is all about leaning. I was always told that whenyou counter-steered, you were forced into leaning into the way you wanted to turn. You can do the same thing by just leaning left if you want to go left and vice versa for right.

Way back in the 70's , when I was just learning to ride, there were pictures of motorcyclists leaning to turn. The pics described an inverted ice cream cone shape (wider at the bottom) and talked about geometry and lean angles. I don't remember all of them, but that is the general theory.

If you think about it, what happens when you turn the handlebars right? You automatically lean to the left, right?

Countersteering works at all speeds. I have used it as slow as 10 mph (I think). I normally don't look at the speedometer at such slow speeds. It is how I change lanes on the freeway as well. Just a little nudge on the left handlebar and I am in the right lane.

Nice discussion.

 

[posplayr]

Try walking a bicycle down the driveway with it perfectly balanced upright and holding the bars very lightly with 2 fingers and turn the bars slightly left. What happens? When I do it, it sure wants to fall to the right. What counter steering actually does is momentarily put the motorcycle off balance by moving the wheels out from under it's line of travel. This is what induces a turn in the opposite direction, not gyroscopic effect of the wheels or other such things. Gyroscopic effect may make it easier or harder depending on the setup but if you had a way of moving the tires out from under the bike in one direction at 0 mph, the bike would naturally fall the other way.

Sandy, (and others)
That is correct but there are still speed related dependencies. I'm trying to keep this discussion practical and not too theoretical and think so hopefully it will be taken in the light. So at the risk of making this discussion even more complex here goes.

See the link below. It tries to answer the question of at what speeds counter steering is more relevant. As you will see in the video below, riders are using counter steering on a Motorcycle at 3 mph and a bicycle at 10 mph.

These are experienced riders and and the link shows how the riders are using the counter steer to initiate a quick turn. If you remember back to your MSF course (I know it was probably 30 years ago for you but 2 years ago for me) where you had to do figure 8's in 1.5 and 1 parking lanes. Well to do that effectively you do need to counter steer to get the bike over in time for the short radius turns. It is like the quick turn the motorcycle rider did at 3 mph.

http://www.obairlann.net/reaper/motorcycle/beginner/countersteering.html

So in general, if you need to get you bike over (into a lean angle quickly), then the counter steer is the fastest way to do that. Ignoring, hanging off or any other weight shift technique, lean angle is a direct function of velocity and turning radius (i.e. G_c=V^2/R; tan(lean_angle)=G_c/G). The smaller the radius for a given velocity the higher the bank. The faster the speed for a given radius the larger the angle of lean.

At low speeds you don't have to use counter steering, I know my ED with round profile tires, turns easily with weight but it will do it faster with a quick counter steer. At higher speeds with an approaching turn, you have to counter steer as any attempt to turn the front wheel will cause your weight to pitch to the outside of the turn and you will feel get that being help up feeling.

So there is a speed dependency of counter steering, as the video illustrates. At higher speeds and higher lean angles counter steering is more or less (an depending upon the bike) a required condition to go through a turn. As a lower speed technique, counter steering helps initiate quick turns which could not be as easily achieved with weight shift.

Jim

P.S. I thought I was doing pretty good recovering from the trip. It seems that sleeping on the ground for a week will take it's toll :-& It was god times. I'm cleaning the road grime off the ED.

 

[Agemax]

Why does a motorcycle work this way? The motorcycle's wheels act like gyroscopes and create gyroscopic forces when moving at speeds above five miles an hour. One of the most interesting effects related to a gyroscope is a phenomenon known as precession. When a force is applied perpendicular to a gyroscope's axis of rotation, the resulting motion is perpendicular to the input force. This motion is called precession, and it's what causes the steering in motorcycles to be counterintuitive.

http://www.youtube.com/watch?v=C7Ow9W0MIac

also known as DRIFTING

 

[Sandy]

Sandy, (and others)
That is correct but there are still speed related dependencies. I'm trying to keep this discussion practical and not too theoretical and think so hopefully it will be taken in the light. So at the risk of making this discussion even more complex here goes.

""This is what induces a turn in the opposite direction, not gyroscopic effect of the wheels or other such things. Gyroscopic effect may make it easier or harder depending on the setup but if you had a way of moving the tires out from under the bike in one direction at 0 mph, the bike would naturally fall the other way.""

Correct you are and I should have included the speed comment in this sentence as gyroscopic effect is a function of both mass and speed (rotation).

 

[Big Al in NY]

If you can turn your bars at speed you're a better man than I.

Exactly, the force you apply to the bars is blocked/met by the gyro effect of a spinning wheel(literally won't let the wheel turn(much, it does move a little)) so your force takes the next easiest(less resistant) path(like electricity) which happens to be leaning the bike over. The more force the quicker it happens. Keep applying force and the bike will keep going over until you stop it. In a tight switch back you're literally lifting the bike back up with the handle bars.
My main ride is a v65 magna with buckhorns. I ride it rather aggressively at times in the twisties. I wish I had a pressure gauge to see exactly how many pounds of countersteering pressure is at the bars at times. Enough to make my arms sore after ripping through the Hawks Nest a bunch of times.

Ever heard of Keith Code's NO BS bike? http://www.superbikeschool.com/machinery/no-bs-machine.php

I don't preach countersteering because I think I'm expert or anything. I don't think I'm the only one who knows about it either. I just know there are a lot out there that don't know about it. I love riding and I want others to love it too(for a long time). I've turned hundreds of riders on to it and haven't had a one not appreciate it. It seems knowing what to tell the bike to do when it doesn't do what it normally does is important?

Big Al

 

[posplayr]

""This is what induces a turn in the opposite direction, not gyroscopic effect of the wheels or other such things. Gyroscopic effect may make it easier or harder depending on the setup but if you had a way of moving the tires out from under the bike in one direction at 0 mph, the bike would naturally fall the other way.""

Correct you are and I should have included the speed comment in this sentence as gyroscopic effect is a function of both mass and speed (rotation).

Actually Sandy you were correct the first time. Gyroscopic has little to do with the 1st order vehicle turn dynamics. Roll and turn rate are related through what is called centripetal (the force on the tires forcing you to continue into the turn) and centrifugal forces (the force trying to push you to stand up from the turn). Gyroscopic is something else and had little to do with these first order effects which is why even the 3 mph low speed turns are aided by the counter steer.

By turning the wheel to the outside at low speed, the small centripetal force and more importantly the weight of the bike cause you to roll into the turn with little effort. When you start actually turning (progressing around a radius) the centripetal force holds you up and stops you from continuing to fall to the ground.

While gyroscopic forces are there, they play a small if not insignificant role in countesteering dynamics. The speed sensitivity I spoke of is that counter steering helps you achieve the desired roll angle faster, the roll angle is a direct function of speed and radius of turn. Gyroscopic forces are related to the 2nd moment (Moment of rotational inertia which is essentially fixed for a given wheel tire) and the speed of rotation alone.

I would not have gotten into a physics description, but we want to quell any notion of gyroscopic having any bearing.

 

[Agemax]

Actually Sandy you were correct the first time. Gyroscopic has little to do with the 1st order vehicle turn dynamics. Roll and turn rate are related through what is called centripetal (the force on the tires forcing you to continue into the turn) and centrifugal forces (the force trying to push you to stand up from the turn). Gyroscopic is something else and had little to do with these first order effects which is why even the 3 mph low speed turns are aided by the counter steer.

By turning the wheel to the outside at low speed, the small centripetal force and more importantly the weight of the bike cause you to roll into the turn with little effort. When you start actually turning (progressing around a radius) the centripetal force holds you up and stops you from continuing to fall to the ground.

While gyroscopic forces are there, they play a small if not insignificant role in countesteering dynamics. The speed sensitivity I spoke of is that counter steering helps you achieve the desired roll angle faster, the roll angle is a direct function of speed and radius of turn. Gyroscopic forces are related to the 2nd moment (Moment of rotational inertia which is essentially fixed for a given wheel tire) and the speed of rotation alone.

I would not have gotten into a physics description, but we want to quell any notion of gyroscopic having any bearing.

I would not have gotten into a physics description, but we want to quell any notion of gyroscopic having any bearing

but it does , THAT IS PHYSICS ffs look up gyroscopic effect on motorcycle wheels

 

[Big Al in NY]

I don't know what it's called but for a simple street rider as myself and I believe most others here, agreeing that the bars won't really turn because the spinning tire won't let them is good enough?

1. You can press or pull on bar.

2. You turn in the opposite direction that you want to go.

3. The bike leans over instead of the bars turning.

 

[Guest]

Can this be moved to Off-topic? I have to agree with the minority, and site BS..... There is no way someone could ride a motorcycle and turn the bars to the right and go to the right, at any speed above 20 or so, this seems like a troll thread.

 

[posplayr]

but it does , THAT IS PHYSICS ffs look up gyroscopic effect on motorcycle wheels

As I previously confirmed, gyroscopic effects does exist as it is one of the terms in rotational equations of motion, however they have little bearing on the subject of 1st order principles of counter steering.

Please refer to your (my) prior Wikipedia reference for any description that provides a determinative relationship between "gyroscopic effects" and counter steering. If you find one, it will be a 2nd order or high order effect. .

The principle effect is how counter steering rolls the motorcycle into a turn. The principle factors are the CG of the combination motorcycle/rider and how far that exists above the road which is the principle center of roll rotation. Compared to the this roll moment of inertia, the wheel moment of inertia is very small by probably an order of magnitude less. Given the low speed counter steering demonstrated in the video, gyroscopic precession is virtually non existent.

I could do some back of the envelope calculation but it should Elbe obvious that gyroscopic progression is not the reason the bike lays down when you steer the front wheel to the outside of a turn. It is the weight of the bike falling when the front wheel moves from beneath the C.G. that causes roll. This can be demonstrated at almost zero speed where the front wheel angular momentum in inconsequential.

Of course at 60 mph, the front wheel angular momentum starts to have an effect that gives the counter steering a different characteristic. However if you recall the simplest high school demonstrations of gyroscopic precession, you will realize that precession can't generate a roll angle. The classic example if to sit in a swivel chair with a spinning wheel while holding the axles. When you try to rotate the axles in azimuth like you would a handle bar, the angular momentum of the wheel cause the chair to spin (assuming your feet are off the ground). It doesn't cause the wheel to roll over as the observed benefit of counter steering is.

 

[posplayr]

Can this be moved to Off-topic? I have to agree with the minority, and site BS..... There is no way someone could ride a motorcycle and turn the bars to the right and go to the right, at any speed above 20 or so, this seems like a troll thread.

how do U figure a technical discussion on motorcycle dynamics is "off-topic"

Never mind it is not OT.

 

[Big Al in NY]

There is no way someone could ride a motorcycle and turn the bars to the right and go to the right, at any speed above 20 or so.

I agree 100% with that but I don't agree with everyone knowing it already. Informing others is why I started this thread and think it should continue. I see in some of the responses there is interest in knowing more and also the need for it. It can be an intimidating subject but once broken down and explained it's much simpler. As a rider you just need to know how to use it.

I was already in the middle of a left turn going straight when I tried to turn left to go left because the bike wasn't leaning like it normally did. I almost wrecked as I kept going straight and realized I didn't have control of bike and didn't know why. It kept me off the road for almost 20yrs before it was explained to me.

My bud "knew how to ride" and had been for 15yrs until his v65 sabre going 115mph on the interstate slowly got ate by a sweeper with me right behind him watching. He couldn't get the lean initiated and was straight up with a last ditch foot stuck out when the bike touched the shoulder dirt and instantly started tank slapping then sliding on the shoulder. The rider IS member Rodman's brother Dave. He was tossed into the medium and walked away with a black eye.

He had heard of countersteering but always thought it was too technical for his simple riding style. Basically he didn't understand it or realize how simple yet important it was and kicks himself for not listening earlier. He uses it now and quite profitiently too.

Sorry for rambling but every one needs to know about it! It's my mission. j/k (sort of)

Nice forum, I've been reading alot.

Big Al

 

[reddirtrider]

I don't think you can turn at speed without countersteering - at least a little. If I remember correctly one of the superbike schools had a bike setup with bars attached to the frame, not the forks and it was almost impossible for the riders to negotitate the track. Wether you know it or not, you're countersteering. Probably not as well as you could, but you are.

Well, I took some time to actually find an article written by keith Code on countersteering. He's the guy that rigged up the bike too, so it's a pretty good read.

http://www.vf750fd.com/blurbs/countercode.html

 

[bonanzadave]

A-friggin-men.

[FONT=Arial, Helvetica, sans-serif]"The Bottom Line. Steering a motorcycle results from the process of pushing the inside bar forward, the same angle and direction the forks rotate in the steering head bearings. You can also pull on the outside bar. You can do both push and pull. That is what turns it, that is all that turns it with any degree of accuracy, efficiency, quickness or smoothness. That and only that, No BS."

[/FONT] [FONT=Arial, Helvetica, sans-serif] Keith Code[/FONT]

 

[gane]

Countersteering

Countersteering

Math and Physics were never my 'forte" however, "countersteering" is a fact. learn it and use it. as unreal as it may sound, during the period of "superbikes", era riders would BEND the then standard '7/8"s bars when changing directions on tight courses, and packed spares.. and, if you read about Bonneville racers, sometimes the rules changed... IE, up to @ 180 it was OK, but after 200 MPH, steering reversed... Different venues offer different skills.In MHOP trials riders are the most skilled, followed by speedway, roadracers,flattrackers, 1/4 milers, then the rest of us. each venue has differnt threashshold levels and danger levels. each offers slightly different teqniques, Personally I'm a dismal trials rider, but the experiaiance I garnered flat-tracking and moto-xing have aided my road racing enourmously. For new riders. Think out your' ride in advance.most newby casualties are from indecision/doing nothing at all, take a class. enjoy the sport, theres nohing like it,luck g

 

[posplayr]

I agree 100% with that but I don't agree with everyone knowing it already. Informing others is why I started this thread and think it should continue. I see in some of the responses there is interest in knowing more and also the need for it. It can be an intimidating subject but once broken down and explained it's much simpler. As a rider you just need to know how to use it.

I was already in the middle of a left turn going straight when I tried to turn left to go left because the bike wasn't leaning like it normally did. I almost wrecked as I kept going straight and realized I didn't have control of bike and didn't know why. It kept me off the road for almost 20yrs before it was explained to me.

My bud "knew how to ride" and had been for 15yrs until his v65 sabre going 115mph on the interstate slowly got ate by a sweeper with me right behind him watching. He couldn't get the lean initiated and was straight up with a last ditch foot stuck out when the bike touched the shoulder dirt and instantly started tank slapping then sliding on the shoulder. The rider IS member Rodman's brother Dave. He was tossed into the medium and walked away with a black eye.

He had heard of countersteering but always thought it was too technical for his simple riding style. Basically he didn't understand it or realize how simple yet important it was and kicks himself for not listening earlier. He uses it now and quite profitiently too.

Sorry for rambling but every one needs to know about it! It's my mission. j/k (sort of)

Nice forum, I've been reading alot.

Big Al

Wow 15 years and doing 115 and did not know what countersteering was. I guess he never took an MSF class? MSF class should be mandatory.

 

[TheCafeKid]

If you want a simple way of examining the effect of "countersteer" without smashing your bike into the pavement, a nice way to check it out is to balance a ball bat or a broom stick in your hand on end. See which way you have to move your hand to get the broom to fall in any direction.

In actuallity a motorcycle, or any two wheeled vehicle is in a constant state of "falling". You countersteer CONSTANTLY whether you're turning or not to keep the bike in line. Its just that the corrections are so minute, you dont even realize you're doing it. In my mind, countersteering has more to do with BALANCE than anything else. When you need to get the bike to lean into a turn quickly, you need to knock it off centerline quickly. As your broomstick will show you, the best way to make the bike fall off center to the RIGHT, is to move the bars slightly to the left.

I think, when everyone sits down and really starts to examine the concept, it confuses people. Yes, its a good idea to understand the basic concept, but a bigger problem, especially for NEW riders, comes from THINKING about it while riding. Its so convoluted and backwards it may actually cause someone to have an accident. Because we've essentially been "countersteering" or better still "counterbalancing" our entire lives, whether it be walking or riding a bicycle, you simply accept THIS is how its suppose to work.

Not long ago, Steve's oldest son brought home a bicycle that was VERY interesting to attempt to ride. It had been modified so that turning the bars left ACTUALLY turned the wheel RIGHT. To ride it, you basicly had to SHUT OFF countersteering in your head...Its very hard to do.

 

[mighty13d]

How it was explained to me is to picture the front tire as two water glasses fused together at the open ends so thats the tallest part at the middle of the tire. If you turn slightly one way, it will make the other side of the tire coming in contact with the road and pull you around just like if you were rolling a glass on a table. It's a very very simplistic view but it helps explain why it would pull you around and how it leans the bike over.