May 6, 2006 at 11:47 am #11990
There are two parts to cornering:
1) To deflect the bike from the vertical you need to countersteer.
2) Once leant over at a constant angle at a constant speed the bike will roll around in a big circle like an ice cream cone.
A motorcycle in motion leans over in corners by balancing the tendency of machine and rider to fall over under its own weight against the centrifugal force which tends to throw rider and machine away from the centre of the corner. To maintain the lean, the motorcycle must continue to follow a curved path by turning towards the direction it is leaning. For a fixed radius of turn, there will be only one lean angle that matches a particular speed.
But to reach that lean angle in the first place, if you want to lean over further or pick the bike up again, you have to make a countersteering input.
How does countersteering work? Well, contrary to popular opinion, gyroscopic forces are not the answer – they contribute (and are easy to demonstrate) but the major forces (some 30 to 40 times stronger) are inertia and camber thrust. Turning the front wheel to one side (we’ll say to the right) has several effects:
a) the machine will turn around the point where lines drawn through the wheel spindles of the front and rear wheels cross each other (intersect)
b) the effect of trail moves the contract patch of the front tyre to one side, so that the centre of gravity of the bike is no longer directly above the line on which the bike is supported between the tyres – the bike will fall to one side
c) the effect of caster steering makes the front wheel lean, so that the contact patch is no longer on the centre line of the steering, and tries to turn the tyre into the corner – this is known as camber thrust.
So basically the inertia wants the bike to carry on in a straight line but camber thrust wants the tyres to turn in a tight circle to the left (roll a loose tyre to see the sort of size of the circle. The force generated by the camber thrust is not strong enough to overcome inertia and make the bike turn in the tight circle it would like but it is sufficient to give the bike an acceleration to the left. The final “set” which the bike settles into differs from machine to machine and may or may not demand rider input and depends on steering geometry, tyres, road surface etc. etc…
Q – Why is it called countersteering?
A – Because you are applying a force to the bars which turns the front wheel right to go left, and turns it left to go right! The easiest way to remember what you need to do is that you need to PUSH the side of the bars in the direction that you want to go – ie you PUSH the LEFT handlebar to go LEFT, and the RIGHT handlebar to go RIGHT. For this reason it is sometimes called “push” steering.
Q – Does countersteering apply to all types of motorcycle?
A – Countersteering works on any two wheeler. You simply turn the bars opposite to the direction you wish to turn. This is usually done by pushing on the inside bar.
Q – Do you push DOWN on the bar, or AWAY from you or what? All my bike does is go the wrong way.
A – First off, push AWAY, don’t push DOWN on the bars – you need to turn the steering around the pivot point of the steering stem. Think what plane the bars move in – if you push down you only try to bend the handlebar. Try pushing down on the handlebar of an XV535 Virago – its almost impossible because the bars are almost at shoulder height. Push away gently on the left handlebar and the bike will lean and swerve to the left. Push away gently on the right handlebar and the bike will lean and swerve to the right. What happens when you release the push on the bars? You’ll find the bike will either stay on the curved path you have set it and continue to corner, or will tend to sit upright – this latter is a self-correcting effect often designed into the steering.
Q – At what speed must one countersteer to turn a bike?
A – Countersteering works at speeds above walking pace. The faster you go, the greater the forces needed to steer the bike. At 20, you will barely be aware that you are doing it, up to about this speed you really don’t have to use much muscle at all, any big push on the part of the rider will have the bike changing direction very violently, enough to lose control. By contrast at 100 you will have to work quite hard to steer.
Q – How do you actually do it though, from the sounds of things you just turn the bars the ‘wrong’ way a bit. Any advice on where/how to practice?
A – Find a straight, empty road or large carpark – you really need around 50 metres minimum length for this, so an EMPTY carpark is ideal. Don’t try it when Sainsburys is busy or down your local high street.
Get up to a reasonable speed – around 20 miles per hour is fast enough for a first attempt if you are in a car park – use the gears, if you hang onto first gear and shut the throttle you’ll get a big wobble with engine braking. Don’t try this too fast to start with, brace your knees against the tank, a reasonable grip (not a death grip) on the bars and keep you elbows loose.
Remember – the amount of effort needed to turn the bike at low speeds is negligible, nor do you need to turn the bars very far. Make sure you use a VERY GENTLE push – the amount of force you need to apply is in the order of the amount you need to push an empty beer bottle over – not very much.
Just use one push on the first few runs so you can learn how much force to use. Practice doing this a few times until you start to get the feel for it. Increase the speed (if you have room) and feel how the effort needed gradually increases.
When you are comfortable with the amount of effort involved, only then try to slalom. Use the painted white lines or something similar – don’t try to slalom round solid obstacles like cars!!!. This is a valuable exercise to repeat regularly or when you get a new bike to ensure you can steer accurately.
Next find a nice straight clear road and try countersteering in a gentle slalom. Don’t frighten car drivers by doing it in front of them. As you get more confident, you’ll be able to swerve the bike harder and harder or at higher speeds. It’s much easier to experiment like this than actually in bends, which should come once you’ve got the feel.
Finally to get the feel for countersteering in a bend, find a corner you know well, with a good clear view, not too fast and not too slow – something in the 30 -50 mph range is ideal. Ride round it a few times just to refamiliarise yourself at a speed and using a line that feels comfortable, and away from the extremes of the kerb and the white line – remember we are trying a new technique and need leeway for errors.
Finally try countersteering into the bend. Make sure the road is empty, and your posture is nice (elbows loose, knees gripping the tank). Approach the corner as normal, getting your braking done in a straight line before you get there to get the bike settled. At your normal turn-in point, actively countersteer (remember the provisos above about the degree of turn and amount of effort needed) until the bike is at the lean angle you need to negotiate the corner. You’ll almost certainly find that you turned along a much tighter line than you expected (hence the advice to only do in a bend where you can see there is no traffic).
Once the bike is turning, you should only need a light grip on the bars, and no real steering input. Remember to turn in on the power, and to keep the power on gently through the corner.
Q – I can honestly say that I have never consciously countersteered in my life and, so far at least, I seem to have survived
A – Well, whether you think you do, or think you don’t, you do. It’s because the amount of deflection that you make at the bars at average speeds and average lean angles is tiny and very short lived, so unless you are consciously looking for it, almost indetectible. Remember, countersteering initiates the turn by getting the bike over off the vertical. Once leant over the bike rolls round like a great big ice cream cone.
Q – The notion of deliberately turning the bars in the opposite direction going round a tight bend is just not on
A – Like any new technique it should be approached cautiously. If you don’t want to try out and practice yourself on the basis of what you’ve read and possibly not fully understood, then have someone there actually to show you how. Any competent instructor should be able to explain and demonstrate countersteering.
Q – I tried countersteering once and scared myself silly – I nearly lost control
A – it sounds like you have pushed too hard in the past and scared yourself! At around 20mph, a very gentle push is all that is needed, so on a reasonably light and agile bike, upto about this speed you really don’t have to use much muscle at all, any big push on the part of the rider will have the bike changing direction very violently, enough to lose control. So take care trying the theory out in practice!
Q – I’m inclined to continue to rely on my instincts – if it ain’t broke don’t fix it!
A – Don’t you think you might improve your riding if you were fully in control of what you do?
Aside from sharpening up your lines around corners and giving you more space to steer round them in, countersteering is also very useful is making the transition from upright to full lean angle VERY quickly, which if you consider it is a good “get you out of trouble” skill. It’s useful when mid corner you realise the bend is tightening up – countersteering more can stop you running wide.
Q – Nobody worried about this countersteering malarkey when I learned to ride 30 years ago, and it was never taught on training courses. I reckon it only applies to those bum in the air plastic crotch rockets
A – The physics behind countersteering apply to all bikes, regardless of age. Older bikes with 19″ wheels and narrow tyres handle differently to modern sports bikes, but then so do modern trail bikes. Countersteering has been known about since the 20’s, the physics first investigated in the 50’s and properly described in the 60’s and 70’s. It’s been the subject of magazine articles since the late 70’s.
Q – Most of the time I’m riding I don’t think about countersteering. Am I doing something wrong?
A – You’re quite right in that 90% plus of the time I’m riding I never give countersteering a thought either…
Where it comes in most useful is as a highly practical road-riding (as opposed to track) skill when you arrive in the midst of an “oh shit” situation. Then understanding and being able to use countersteering positively is a huge plus point.
Q – So what advantages are there to countersteering?
A – Once you know how it works you can choose whether to use it consciously. If you do, it’ll allow you to brake later and keep the bike upright for longer in the turn, thereby allowing you to see further through the turn. It’ll allow you to get the bike upright sooner, and get back on the power earlier, getting better drive out of corners. Not least it allows you the option to keep away from potentially dangerous extremes of position to either side of the road – in other words it gives you more space to choose from on the road.
As regards speed, between about 20 and 50 you can improve your turning with a positive decision to use countersteering – you can still turn without feeling what you are doing or thinking about it, but by using countersteering you will improve both the speed at which you get the bike to full lean and also your placement in corners… this is what I mean by medium speed, but the forces you have to apply are still fairly small..
Over 50 you are now having to turn the bike fairly quickly to get round bends on anything other than motorway or Roman road, so you need positive input, and of course the forces are increasing… by now you are starting to notice that you are actually doing physical work, particularly if you are riding a bike that doesn’t turn easily… this is what I mean by high speed, and now actively deciding to countersteer has huge benefits in terms of control…
Clearly these figures are guestimates, and depends on bike, road, loading etc. etc., and there is obviously no real boundaries but I think you will get the idea…
Q – So do you do anything else in corners apart from countersteer?
A – Another important factor in cornering is throttle control. Don’t coast round bends, but gently put the power on all the way through the bend, this will stabilise the bike.
Don’t forget posture and relaxation. Many riders are far too stiff. Relax your elbows and upper body, make yourself flexible and brace your knees against the tank. And remember not to negate your steering effort by pushing on the other side of the bars at the same time.
Q – So how do we use countersteering with braking and acceleration?
A – It works with the standard technique for taking corners which is elsewhere on the site. As soon as you see the next corner you should :
* Set your position in the road
* Sort out your speed, braking in a straight line if necessary,and getting it in the right gear
* Drive through and out of the corner with the throttle
Q – These techniques are race stuff. Countersteering is something you only do on trackdays and sportsbikes.
A – I disagree. The more skills you understand and can use, the better. It doesn’t mean that your knowledge obliges you to ride fast, but if a corner tightens, or you need to avoid a Volvo, then the techniques to change direction hard and in control are very useful.
Q – So countersteering is the only technique to use in corners?
A – No, that’s too simplistic too. Countersteering works as a stand-alone technique. It’s by far and away the most important, and the other techniques are very relevant and complementary, but only when used in conjunction with countersteering.
Used together, they put you in full control of steering.
Q – One thing I don’t understand: the faster you’re going the more you need to countersteer; but at low speeds, you don’t countersteer. Does this mean that there is a certain speed at which steering has no effect or has an unpredictable effect because it’s too fast for “normal” steering and too slow for countersteering?
A – The maths shows that for a conventional bike countersteering works from about 5mph upwards. By about 20mph, the forces needed to countersteer are big enough for you to be able to feel them and steer smoothly (the forces below about 20 are so small that it’s difficult to steer smoothly and light bikes with wide bars make it more awkward still due to the small mass and increased leverage). By the time you get up to 100mph+ you need serious muscle to turn the bike fast.
Q – I understand countersteering and use it all the time – but I find when the bike is leaned over I have to keep a force applied to the bars to keep it on line
A – This is down largely to steering geometry and tyres and you will feel this as whether the bike naturally oversteers, understeers or is neutral steering in corners. Most modern bikes are set up to understeer, so that you have to keep a small amount of steering effort applied to hold a steady line against the bike’s natural tendency to straighten up. Some of the 80’s 16″ front wheel bikes oversteered – they used to flop into corners and felt very unstable indeed at low speeds. As the speed goes up, the self stabilising effect usually increases so the bike feels more stable when turning.
Q – Somebody told me I need to oversteer into a corner if it tightens
A – Confusion of terms! The main thing to remember is that to ALTER the lean angle of a bike either in the initial turn-in phase of cornering or mid turn use a technique we call countersteering. What we call oversteer (or understeer) is the tendency of the bike to deviate from a CONSTANT turn radius constant. This is a result of a whole mess of forces operating on the tyres and the geometry and design of the bike. You may still be applying a force to maintain a constant radius turn, but it is not called countersteering! For example, if you are pushing the left bar through a left turn to keep the bike on line, you are correcting for UNDERSTEER – if you didn’t the bike would run wide in the turn.
Q – You tried hanging off and countersteering?
A – Yes, and it still works. In fact, in my opinion it puts you into a better position to countersteer because hanging into the corner gives you more leverage on the inside bar.May 14, 2006 at 11:25 am #48727
That’s really good Gix
But you forgot one thing…
Counter steering is bloody well amusing on a 50mph sweeping-country-road-corner! you get a buzz like no other when you first do it… it’s fantasticMay 14, 2006 at 12:26 pm #48728
Levi, it does not matter what speed you are travelling, you are doing it at anything above brisk walking pace, you just arent conciously aware of it.
Using the conscious knowledge of doing it, to drop a bike rapidly into a corner however, does give a buzz, but then the buzz is there everytime I swing leg over bike.May 14, 2006 at 12:42 pm #48729
Originally posted by Gix
the buzz is there everytime I swing leg over bike.
Yeah, but it’s different for girls you put your helmet on back to front remember? hehe
I didn’t think I really needed to specify having conscious knowledge of doing it, I would have thought that was obvious I was talking about it hehe
I was very lucky though, I got taught how to counter steer on my intensive course, and as a rule people are not usually taught this unless they are on a DAS (so my instructor tells me)May 14, 2006 at 12:47 pm #48730
as a rule people are not usually taught this
Thats because knowledge of doing it is not essential to passing test, it comes naturally, though knowledge of how to control imput where, can be very useful as experience progresses.
Having said that, I think that it should be touched on at the very beginning of a new bikers motorcycle training, ie the CBT, as the ‘concious’ knowledge and effort of doing it can help in sticky situations.May 14, 2006 at 1:04 pm #48731
I agree there, because they do NOT tell you that at any sort of speed the steering, essentially, reverses…
Now what happens if a CBT-er goes out on the road at the end of the day, get’s into a pickle and thinks “Right, I better swerve to the left otherwise I’m going to crash”
So they grab the bars and yank them to the left, and they, to their surprise, rocket to the right into on coming traffic… game over.
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