Countersteering / Counter Steering / Gyroscopic Merged Threadfest

[johnr]

Perhaps he means from the horizontal. That would give him 26 degrees.
I had a friend who achieved 45mph on his racy treddly coming down Dyers Pass road (Port Hills Christchurch) once.  He got a speeding ticket for it and was quite proud of it. I thought he was nuts.

[rudyr]

don't forget you or sitting on three gyroscop when riding on a moving motorcycle.  with rotation you have what we use to call regegative.  when you try to turn a gyro it will tilt and if you try to turn it, it will tilt.  but all effects take place 90 deg. in the direction of rotation.  why do you think when coming to a stop lite if you rib  your engine up it want's to stand up more by it's self.  That's a five min. course on gyro's and motorcycle.rudyr

[johnr]

I have received some requests to repost this blurb and am happy to do so if someone finds it either entertaining or useful.

The thing is, that in my experience using counter steer pressures to steer the bike actually works.  And further more makes riding a much more relaxed experience.  The why of it is less important (and much argued about)

I wrote an article once about this, and may have even put it on this board on one occasion, I can't quite remember. Anyway the first part of it describes how I came to learn about it and I'll include that below.

I hope that even if it doesn't convince you, that at least it will prove an entertaining read.

Please do remember that this was written for a very different audience than this one.

Her it is.

Ever notice how you can always pick a novice rider? They teeter. So, way back in the mid 60s I was teetering about the place on the old 650 I had in those days. When I parked up outside the Fountain Coffee Bar an old hand called me over. The Fountain Coffee Bar I should mention was the place where such people tended to hang out, there was often a line of bikes outside and it was of course, the social centre of the universe.

This chap advised me to steer with my knees. Push the tank though the corner with your knees he said, and let everything else follow. My riding improved 300% overnight and I then had to find some other excuse to fall off.

If you quiz a rider that has any kind of decent miles up you can usually get them to admit, somewhat shame faced, that at least once while cruising along a sealed road at sealed road speeds and looking at the scenery they had inadvertently drifted into the gravel at the side of the road.  This is a pucker moment and tends to bring one back to the task at hand rather promptly. The thing is, they get stuck there. They find that the bike doesn't seem to want to get back out of the gravel.

This happens because they are scared to lean the bike in gravel at those speeds and try to just steer it out. It doesn't work. No lean = no turn. When they try to steer it out of the gravel the bike tries to go the other way. Teetering again. In the end, they either get over it and lean, come to a stop, or come a gutsa. (fall off)

Not knowing the mechanics of this caused my Rocket 3 to ride my leg over a gutter while on it's side (removing a few chunks of said leg) then to whack a wooden telegraph pole with its headlight, (just before my head did). It then rolled up the road doing itself a considerable mischief in the process.

Fastest ride in an ambulance I've ever had!  Fortunately I looked worse than I was and was kicked out of the hospital the following morning.  My somewhat drunk middle aged passenger had scribed a graceful arc into a nearby hedge. Not only was he wearing my helmet (which I would rather liked to have had on my head at the time) but my reaching round to stop him falling off the back seat set the whole incident into motion.

We were both leaning left causing the bike to start turning to the left. I was hanging onto the right handle bar which I pulled hard on to try and straighten the beastie up!   INSTANT DISASTER .

The point is that in those days (1972) reverse (counter) steering had not been heard of by the general motor cycling public and the cause of this prang had me truly puzzled (especially as after thumping my head with a telegraph pole I did not remember much about it all until quite some time afterwards)

The only people in those days who fooled with the sacred cow of frame design were the chopper boys and their magazines were 90% strictly low grade entertainment. It was through one of those mags though, some time later, that I first learned about reverse steering. The traditional light bulb appeared above my head and illuminated the surroundings quite nicely.

I took the bike out onto a nicely deserted motorway early that Saturday morning, got up to a nice stable cruise speed of about 70mph, and took my hands off the bars. (I should perhaps point out that Brit bikes in days of yore, had a brake built into the throttle. I liked mine set so that the throttle would just stay where I put it.)

I extended my pointing finger and gave the right hand grip a bit of a prod. (to turn the bars left) The bike immediately leaned and turned to the right! All by itself!

I would have liked to spend a few moments with an expression of shocked amazement on my face at how well this had worked, but the fact was that the three foot high concrete motorway divider I was turning towards was arriving rather rapidly.

I duly prodded the left grip (to the right)  with my left nostril picker and the bike leaned and turned to the left with casual aplomb and precision. Another right hand prod had me straightened up again. I went home and didn't think much more about it.

A few months later I was doing my annual major tour and was heading up to a place called Queenstown from a place called Invercargill. This involved some very scenic stuff especially a stretch called the Lake Road which winds around one of the  mountain ranges that contain Lake Whakatipu. On a bit called the Devils Staircase, cliffs beside you, a 250 foot vertical drop to the lake, 15 kph  (10 mph) corners, Beware Falling Debris' signs  and all that sort of stuff, (who is this 'Debris' anyway?) I stopped to relieve myself.



Just as I was getting underway again a green sports car decided I shouldn't be there  and had a go at running me off the road!   I've refrained from quoting the kind of words that went through my mind, but it was definitely time to be elsewhere.

Well, a major adrenaline rush and full throttle wasn't enough. Rocket 3s didn't develop a whole lot of noise until you got to at least 3000rpm  and if you really let rip and dumped the clutch you wore out a TT 100 tire and got no where. All that happened was that I got up to 70mph before I was successfully run off the road.

There I was , stuck in  a 1 foot wide gravel verge with a huge drop beside me, a very, very sharp right hand corner arriving very fast and a vast drop dead ahead. There was absolutely no way I could take that corner using the gravel verge.

Dead was the appropriate word too. There was absolutely no way out of this one. I was, as the saying goes, a goner. This was so certain that I had got beyond panic and had gone into the calm peaceful acceptance phase. ... Interesting actually.

Meanwhile, the back of my mind was flipping through dusty files, sweat running down its forehead looking for something that could be used.

The distant memory of a certain afore mentioned light bulb...  What the hey, I had nothing to lose, may as well try it.
 
I turned left, off the road!  The bike popped up to the right onto the seal and hurtled round that sharp right hander, me hanging off the side of the tank and everything scraping and sending off showers of sparks.  There were just inches to spare between my tires and the edge of the seal and the long drop.

I gradually got slower and slower until I got to a pretty little mountain stream. Walked upstream for a while, sat down, had about 6 cigarettes and shook like a leaf in wind tunnel.

For the thousand odd miles back to Auckland I practiced reverse steering.  I found it to be a very precise and easy way to corner.

The thing I had to unlearn was the mental association of turn left, lean left  In effect what was happening then was I would find my bike wanting to go one way and me trying to lean the other. Not good. Once I learned to trust the bike to take up the angle of lean it wanted for a corner and just sit on the centre of gravity and go with it, it all came together.

I have ridden using only that technique ever since. No more having to lean the bike or throwing my body about,  I just sit there like a sack of spuds looking at the scenery or what ever and let the bike take me where it will. All I have to do is push the bars the wrong way.

I should emphasise that when I did the experiment on the motoway mentioned in the above article I noticed that when I pushed the the right hand handlebar to the left with my finger the bar actually came back towards me so at no stage did it appear to actually turn to the left. Rather the pressure on the bars to do so resulted in an actual turn to the right.

The reasons why reverse steering should be so (or not) is the subject of a great deal of argument and debate.  Why this should be so is a bit of a mystery to me as the physics of rotational dynamics are available to any who cares to study it.  It does seem very odd to my mind though that given that it works can be determined with simple experimentation and experience that people would set out to prove that it doesn't. 

Every argument or experiment that tries to prove that it doesn't work comes up against one inescapable problem. It does work, as anyone can determine for themselves.

The why of it is a whole other question though and all I can do is offer up my understanding of it which may be right or wrong.  It seems perfectly simple to me though and I've yet to hear anything that modifies my understanding of it.

Here then is the second part of the above article for your consideration with a repeat warning that it was written for a very different audience than this one.

The how and why of it

Two big words. Gyroscopes and precession.  Enough to put any one off, but it's not hard.

A top is a gyroscope. You have all seen a top. You spin them up and they sit there on their pointy little heads spinning away merrily and not falling over.

Your wheels are gyroscopes. The forces that allow a top to balance are the same ones that hold you up on a motor cycle. It is not your balance, nor your movement, it is the wheels spinning. That is why you have to put your feet down when you stop. That is why it is harder to perform very slow speed maneuvers.

That being firmly established it is reasonable that your wheels should behave like gyroscopes and as chief pilot, equally reasonable that we have some understanding of this. This brings us to Precession. Now we don't need to worry about why precession works, you can find that out if you are interested enough, we only need to know what it does, and how that affects our bikes.

Here is the rule;
If you apply a force to the axis of a gyroscope, the action will take place 90 degrees in the direction of rotation.

For example. If you have a top spinning away and singing little top songs to itself on the desk in front of your keyboard, and you were to give the top of it a wee push to lean it toward the monitor, it will tilt, in fact, at right angles to the push.  (which way depends on which way it is spinning)

Try it if you don't believe me, but don't be a bully. Remember you are much bigger and stronger than the top and can easily overpower any of the little forces a top can generate.

Now it is time to get out the felt pen and the table cloth. We need to draw/ imagine a hypothetical motorcycle with forks on it that are straight up and down, No rake, narda, zero.  The front wheel is just like the top but is operating in a different plane. A sideways operating top. Forces applied to the handle bars can be translated as though they are directly applied to the axle, which of course they are, so we only need to look at forces and angles at the axle.

If you applied a force to turn the wheel, say to the left, it doesn't go there. The action takes place 90 degrees in the direction of rotation. In this case the wheel would not turn anywhere. It would just lean over to the right. You would hypothetically fall off.

Now,  when we hypothetically return from our hypothetical hospital,  we modify our hypothetical bike to have some angle on the forks. For the sake of clarity, let's make it 45 degrees.

This time when the force is applied to turn left, it's not a horizontal force, but one that's on a 45 degree angle. So it's going to try to turn and lean the wheel to the left, ( not just turn it) but round we go 90 degrees in the direction of rotation to the direction  the action takes place on the axle, and it actually turns and leans to the right!

The relationship of lean to turn depends on the actual angle of the forks. Fork rake (angle) also affects other quite important parts of your handling, but they have no place in this already overly lengthy diatribe.

What it means is that if you apply a force to your handlebars to turn left, your bike will turn and lean to the right.. You need to be prepared to go with it.

When you go round a corner you are doing this in any case. You are just applying the same forces from a different direction. But, as I pointed out in the story section, not knowing how this worked caused the nastiest accident I've ever had, and later, knowing it saved my life.

There has been some discussion as to whether it is better pull on a bar to turn, or push on the other side. Theoretically it shouldn't matter, except for one thing.

When you pull on, say the left bar to turn right, there is a tendency to pull yourself a bit upright. Your body weight then partially resists the turn. On the other hand if you were to push the right hand bar to turn right, your body tends to follow it a bit, enhancing the turn.

For that reason I think push is better than pull. Anyway, it is easier to remember Push right, Turn right

A little addition


 

I knew I had one somewhere!

This shows one of those toy gyroscopes that you can buy. See how it is only being supported by the string at one end? (It is spinning)

It's our 90 degree rule in action. The weight of the thing is trying to tilt it down, but the action takes place 90 degrees in the direction of rotation, so it is turning round the string instead.

One thing that is not made clear above is that a gyroscope, like anything else, will keep doing what it's doing once the forces are balanced.

What that means is once you have applied the force to set your bike into a curve it will just keep on in that curve until you (or some other force like a road irregularity) do something to change it.

That means that once cornering (given that it is a constant curve and you got it just right) you could take your hands off the bars until it's time to straighten up again (or turn out of the curve).  I have tried this and it works, but the realities of roads means it is probably wiser to keep at least one hand on the bars for minor adjustments.

[oldbike54]

 Thanks John . One of the most concise explanations of how a motorbike works I have ever read  Funny also , always makes things easier to digest 

  Dusty

[johnr]

No problem Dusty, and thanks.
If you like the blurb it may pay to grab a copy of it for yourself.

[guzzimike]

You guys are overthinking it.

It is very simple.

Aim with your inside shoulder at your intended line trough the turn .

There. Insta-Countersteering...  

AND, as a bonus; now you will be smoother through those turns.


BTW, this aim-w / shoulder method also keeps you from "Target Fixation" , as the line which you are aiming on is constantly upgrading itself.



-

[Old Jock]

I agree Mike

My method is a bit different but achieves the same thing through body action. I take my butt just off the saddle and move my body into the curve looking where I'm going through the curve with my head out into the curve. So my whole body is leaning into the curve, knee up or down as I choose. t Its not a lot, the movement when viewed from behind is barely discernible.

The action of moving my body, especially upper part, into the curve pushes my shoulder and arm on the bar, so I'm countersteering using my body. I just find it a more flowing method.

The only time I use the direct heave onto the bars is in an emergency where something unexpected occurs and I have no time to set up.

Its just the best way I've found, when I first got the Daytona I was months trying to get it to turn, as it was the first bike I had with something approaching modern rubber plus its was a lazy sod anyway and needed a good prod to get it to move from the vertical.

John

[Chuck in Indiana]

That means that once cornering (given that it is a constant curve and you got it just right) you could take your hands off the bars until it's time to straighten up again (or turn out of the curve).  I have tried this and it works, but the realities of roads means it is probably wiser to keep at least one hand on the bars for minor adjustments.

Absolutely. Once flicked into the turn, the machine is stable, and doesn't need or want you messing with it.. EXCEPT you are now on the side of the tire, and it is essentially smaller in diameter at the contact patch, so it needs to be rotating faster. Adding throttle all the way through the turn stabilizes the bike and makes for faster exit speeds..

[56Pan]

Absolutely. Once flicked into the turn, the machine is stable, and doesn't need or want you messing with it.. EXCEPT you are now on the side of the tire, and it is essentially smaller in diameter at the contact patch, so it needs to be rotating faster. Adding throttle all the way through the turn stabilizes the bike and makes for faster exit speeds..

And it just feels so good.

[Kev m]

The action of moving my body, especially upper part, into the curve pushes my shoulder and arm on the bar, so I'm countersteering using my body. I just find it a more flowing method.

At this point, isn't this just semantics. At the end of the day, it's still the movement of THE BAR that accomplishes everything, no?

[Old Jock]

Yes Kev I wouldn't say its necessary semantics, by using my body I'm also slightly lowering the CG too and I find that this action allows me to initiate a smoother transition. But that's just what works for me

However Yes absolutely it is the action of pushing the bar in the desired direction is what is causing the bike to turn

[Rough Edge racing]

At this point, isn't this just semantics. At the end of the day, it's still the movement of THE BAR that accomplishes everything, no?

 Yes pretty much so.....Riding at let's say 50 mph with hands off the bars and and steering with body English....You lean your body to the left and the bike drifts to the left...Have the bars moved to the right? Maybe no so with a very slight turn... I do this from time to time but never paid close attention to the bar position...

[Kev m]

Yes Kev I wouldn't say its necessary semantics, by using my body I'm also slightly lowering the CG too and I find that this action allows me to initiate a smoother transition. But that's just what works for me

However Yes absolutely it is the action of pushing the bar in the desired direction is what is causing the bike to turn

Don't get me wrong, I'm under the impression that what you are doing is all good technique.

By shifting your weight, and lower the CG a little, you're also setting up the bike so that it can turn with LESS lean angle (the weight shift allows it to reach that point of balance sooner) and I would argue that's more safety margin especially on the street right?

Yes pretty much so.....Riding at let's say 50 mph with hands off the bars and and steering with body English....You lean your body to the left and the bike drifts to the left...Have the bars moved to the right? Maybe no so with a very slight turn... I do this from time to time but never paid close attention to the bar position...

I honestly can't answer that. We've reached my unimpressive limits in knowledge of physics.

I'll once again say that the NO BS bike demonstrates we're not going to actually initiate a turn with the body English.

But I'll agree I've felt a wobble or drift if I've played with body English.

And I think we all do agree that body English has an effect on a turn (like I just said, you can change the balance point with body positioning for sure).

I will say that on yesterday's relatively brief ride I tried verifying bar movement and positions before, during, after turns and it reminded me that part of the problem with these discussions is that the movement is MINISCULE... I mean we're talking a few degrees makes all the difference (at least in the big sweepers I was riding yesterday).

Ohh, that reminds me of something funny I saw... time to start another thread.

[Old Jock]

No offense at all Kev known you long enough "virtually" to understand where you are coming from.

I don't understand the term full body English, but my impression is when just leaning the bike, it will initiate a wide turn or general drift in that direction. Of course that could also be another input, I'm unaware of too, I never gave it that much thought.

On the no hands thing it took me a ridiculous amount of time to discover that hands off and sitting back, more upright, the bike will quite happily track by itself. However the further forward I lean towards the bars the more unstable it becomes. Same thing for the bicycle. 

My unscientific anecdotal evidence also tells me that on more modern rubber, i.e. wider, the actions require to be accentuated more. If on the Sfida (LM 1000) it turns ridiculously easy (input wise) compared with the 1098. Its not that the Sfida is faster into the turn there just seems less effort required on the skinnier rubber. On the other hand the 1098 feels a lot more stable in the turn and less nervous.

[Kev m]

I don't understand the term full body English, but my impression is when just leaning the bike, it will initiate a wide turn or general drift in that direction. Of course that could also be another input, I'm unaware of too, I never gave it that much thought.

Did you watch the video of the no BS bike.

I believe it clearly demonstrates that you can't really initiate a turn (for all practical purposes) with JUST a lean.

That's all I'm saying.

You need an input at the steering head because of the extent of the forces involved in a motorcycle.

Bicycle is a different matter, because you and your weight far outweigh the forces involved (the mass of the bike and generally any speed/momentum/centripetal force)... of course, even then I'm not sure, it's been too many years since I rode a bicycle without hands as a kid, maybe my leaning turned the steering head even then.

[Triple Jim]

You can steer a bicycle by just weight shifting and leaning, Kev, but in practice it's sloppy compared to using the bar, and it works best at relatively high speeds.  Generally things are very similar between a bicycle and a motorcycle, as far as steering technique.  Things just happen quicker on a bicycle because of the shorter wheelbase and much lower masses involved.

[Old Jock]

Did you watch the video of the no BS bike.

I believe it clearly demonstrates that you can't really initiate a turn (for all practical purposes) with JUST a lean.

That's all I'm saying.

You need an input at the steering head because of the extent of the forces involved in a motorcycle.

Bicycle is a different matter, because you and your weight far outweigh the forces involved (the mass of the bike and generally any speed/momentum/centripetal force)... of course, even then I'm not sure, it's been too many years since I rode a bicycle without hands as a kid, maybe my leaning turned the steering head even then.

Yeah Kev seen that video and I agree with what you are saying.

When I say lean with hands off though I do get a turn of sorts though, its a ridiculously wide turn and not much use for anything. Simply that anecdotally that shifting weight does have an effect albeit marginal.

As a practical technique its useless.

As others have already stated my understanding is the countersteer initiates the turn, the narrower wheel radius when leaned in is what actually makes the bike turn.

[donn]

Bicycle is a different matter, because you and your weight far outweigh the forces involved (the mass of the bike and generally any speed/momentum/centripetal force)... of course, even then I'm not sure, it's been too many years since I rode a bicycle without hands as a kid, maybe my leaning turned the steering head even then.

Even on a bicycle, though you can initiate a turn with body weight, it's also "not much use for anything."  I far as I know, countersteering isn't just something you do in an emergency, it's the way we normally start a turn, on a motorcycle or bicycle.

[Kev m]

 

[LowRyter]

I can't wait until we talk about "trail braking".

 

[johnr]

Absolutely. Once flicked into the turn, the machine is stable, and doesn't need or want you messing with it.. EXCEPT you are now on the side of the tire, and it is essentially smaller in diameter at the contact patch, so it needs to be rotating faster. Adding throttle all the way through the turn stabilizes the bike and makes for faster exit speeds..

Chuck, do you think that the small, if any, change in diameter is significant? I can't say I've ever noticed it.  Of course, if you are doing something other than just cruising along then having a bit of power on in a curve is a good thing anyway.

[Kentktk]

Chuck, do you think that the small, if any, change in diameter is significant? I can't say I've ever noticed it.  Of course, if you are doing something other than just cruising along then having a bit of power on in a curve is a good thing anyway.

You don`t notice anything because the statement is not true.

[Chuck in Indiana]

You don`t notice anything because the statement is not true.

And what makes you say that? When you are on the side of the tire, the effective diameter is smaller.

[biking sailor]

Resisted saying this long enough, about to bust!   

After discussing this with my kid, shortly after a call from Dusty, he put a zip tie on the handlebars between the clamps extending the end straight back.  Then he put a piece of marked masking tape across his tank to form a scale.  This was on his Street Triple.

With his helmet cam running, he recorded the results.  Countersteering starting the turns, then, and hard to tell, but looks like turning into the turn to maintain at slow 30 MPH speed turns, neutral to more very slight countersteering to maintain higher speed 60 MPH sweepers.  Body steering, no doubt about it when he leaned hard with hands off the bars at 60 MPH, as the bike SLIGHTLY fell over into the turn the bars turned away from the direction of the lean, which means he initiated a countersteering turn with his body weight shift.

I'll post the video, or link, when he gets around to posting it on his blog.

For those with a GoPro, or such, try it yourself and compare results.  I'd love to see more videos of what happens on other bikes with different geometries (rake, trail, wheelbase, tire width, CG...)

[Kentktk]

With his helmet cam running, he recorded the results.  Countersteering starting the turns, then, and hard to tell, but looks like turning into the turn to maintain at slow 30 MPH speed turns, neutral to more very slight countersteering to maintain higher speed 60 MPH sweepers.  Body steering, no doubt about it when he leaned hard with hands off the bars at 60 MPH, as the bike SLIGHTLY fell over into the turn the bars turned away from the direction of the lean, which means he initiated a countersteering turn with his body weight shift.

He was already in the turn after countersteering was initiated. Have him try the same thing to initiate a turn, body weight shift doesn`t work

[donn]

Countersteering starting the turns

That's the deal, it's how we all start turns.  You can't stay with it, though!  the countersteer moves the bike out from under its center of gravity, for the lean.  You can't keep that up for long, or the bike will keep moving out from under its center of gravity until it's sliding along on its side.  The tire contact patch goes where you point it, not the bike's center of gravity.

[biking sailor]

Semantics, means hard to describe. 

Slow motion appears the counter steering is not turning the bike, only making it lean. Same with hands off. The sudden weight shift caused the bars to go slightly opposite, with a little lean, then back immediately to straight. No real direction change. In the middle of all the turns, the bars were center to pointing in the direction of the turn.

[redrider]

as the bike SLIGHTLY fell over into the turn the bars turned away from the direction of the lean


Yes. The mass of bike to overcome the forward inertia far exceeded what the human input provided. The front end was attempting to maintain the balance of the straight and level before the human input.

Trail Braking is a topic that is showing up in classroom discussions. Oil and tire threads used to be the hotties.

[drums4money]

There's got to be an Ivy League Dr. of Physics that can help counter steer us in an acceptable direction.  I'd like to see what a little official science smells like. . . .at least that's how I'm leaning.

[johnr]

And what makes you say that? When you are on the side of the tire, the effective diameter is smaller.

Agreed.

The thing is, I would posit that given the width of the wheel etc that the change in diameter is very small indeed and I have a big doubt that it has any effect on steering.  Nor can I think just now of any reason why it should. 

The effect of that change of diameter would seem to me to be either that the wheel speeds up by a small amount or that the bike slows by a small amount or both.

That would make sense because in "physics speak" a turn or change of direction is an "acceleration" (in a given direction) and requires energy which would be sapped from the bike speed. (or provided by more throttle)

While I don't think the diameter change has any relevance to steering practices I remain open to the possibility. Unconvinced as yet though.