Moto-Myths 2: How to Steer a Bike

Conventional (non-biker) wisdom says if you turn the wheels left you will turn left, if you turn the wheels right, you will turn right. With motorcycles, however, you turn left to go right: this is called counter-steering.

Physics 101

The theory of this is actually pretty simple: 2-wheeled vehicles turn by leaning in the direction of the turn. Lean a bike left, it turns left; lean right, turn right. The problem is a motorcycle has too much mass to be easily leaned over once it’s moving. This is where counter-steering comes in…

Q: If you were riding a bicycle and some bully were to run along side and turn your handlebars violently to the left which way would you fall?

If you said “to the right”, then you’re correct. A sharp left would drive the wheels to the left forcing you and the upper part of the bicycle to fall to the right. This is the key to how you steer a motorcycle. By turning the bars to the left the front wheel pulls to the left leaning the motorcycle to the right, allowing you to turn right. Because 2-wheeled vehicles turn by leaning in the direction of the turn.

How come some experienced motorcyclists disagree?!?!

This is what I find so interesting! There’s a lot to be said for instinct. People can counter-steer (to an extent) instinctively without realizing what they are doing. Bicyclists often counter-steer without realizing it, and so do some motorcyclists (usually Harley-type riders). What they will tell you is that they simply “lean in the direction of the turn to get the bike to turn…”

But what they are really doing is…in the act of trying to lean, they are gripping the handlebars and counter-steering. I can prove it. Sit on your bike and hold the bars with your elbows somewhat stiff (the way you would if you were trying to move something heavy) and lean your body to the left. Which way are you turning the front wheel when you do this? By moving your body to the left you are actually steering the front wheel to the right. Counter-steering!

Not only that, Keith Code’s “no BS (body steering) Bike” shows that it’s impossible to effectively steer a motorcycle at speed simply by leaning. All those “lean-ers” are really just counter-steerin, but they don’t know it. Monkey bars and similar Harley-type contraptions additionally force you to lock your elbows as you “lean” causing you to counters-steer more easily.

More theory…

So does this mean that when a motorcycle is in a turn, the front wheel is faced in the wrong direction? No. The wheel is faced more or less in the direction of the turn, but in the act of leaning (or leaning further) it faces further out of the turn… So if you’re making a constant left turn (in a circle) the bars would point left. But in order to get the bike to make an even tighter turn to the left you would “push” on the left grip causing the bike to lean left even further. During that whole time the front wheel would face left, but at the moment you make the steering input it would face slightly less to the left.

So do you have to continually counter-steer in a turn, or is it just to initiate a turn?

It depends on how far you are leaned over… If you are going for a full lean, Moto GP style, or a very slow turn at a moderate speed, the answer is: you only need to counter-steer to start the turn – once you’re in the turn the wheels follow the arc of the turn.

But there are speeds and lean angles at which you may have to keep applying the steering input for as long as you are turning at that speed and angle. So often times in spirited parkway riding you need to counter-steer, hard, and keep pressing in order to maintain the arc, otherwise the bike seems to want-to straighten out.

…If all that confuses you – then forget it, the theory is not all that important as long as you get the feel for it.

How the Pros Do It…

This is how expert bicyclists, scooter riders, and motorcyclists turn their bikes. Scooters and bicycles can-be turned by forceful leaning (usually), but when you watch skilled riders, they don’t whip their bodies around – they steer. How do you steer your bike?

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PS – So for those to whom counter-steering is a new idea, here’s a little exercise you can do on an empty street. At a moderate speed (30mph or so) make S-lines across the center of your lane. (Make sure there are no cars behind you…) Lean forward so that you can reach the handle bars while keeping your elbows bent. Push on the right grip to lean right, left grip to lean left. Try not to move your torso relative to your bike, but use only your arms. Gradually make sharper “esses” as you get the feel for how the steering works.

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8 responses to “Moto-Myths 2: How to Steer a Bike

  1. This is a very good description of the steering.

  2. Okay, so if I slightly turn against the corner (e.g. to the left, on a right-hand corner), my weight will shift to the right, making the right turn smoother, right?

  3. Hey Kolyn – jump over to the new location:

    http://www.citybikerblog.com

    When you’re going 30mph (or faster) on a motorcycle, there’s no way to lean right without turning the front wheel slightly to the left…counter-steering.

    As you turn (the front wheel) LEFT – sometimes just momentarily (until you reach the lean angle), but sometimes with a constant force (throughout the entire turn) – as you do that, the bike leans and turns right.

    Strange, I know. This is why so many motorcycle accidents are single vehicle accidents – newer riders don’t know which way to turn and wind up crashing.

  4. Hi there. I was talking with my cousin about it…
    I’m 37 years old and i ride motorbikes more then 20 years…
    If i lock the steer somehow and ride the bike, the bike will turn the side i lean my body and the bike, of course.
    I do use counter-steering when i use drift technique while turning…
    I agree with all you say exept that when i want to turn left, i lean my body and the bike to the left and use steer for corrections.
    Greethings from Greece..

  5. I think i got it…
    Counter-steer helps me to lean the bike the direction i want.
    So if i want a left turn, i momentarily turn right, to get the bike lean left.
    Correct?

  6. Counter-steering is essentially correct.

    I am surprised that so little is written in layman’s terms about the physics of bike wheels. In fact, some scientists are still arguing about whether gyroscopic effects keep the bike from falling over when it’s moving (they don’t)!

    So how does a bike stay upright and why does it steer in an arc when it leans over? Why, for example, does it not carry on in a straight line just because it’s leaned over?

    To answer both these questions, consider what happens when you roll a coin (or a bike wheel) on a smooth surface. The coin will roll straight and remain upright until it loses momentum.

    What is generally not understood is how the spinning wheel remains upright. The truth is that as soon as a small wobble to one side occurs, the leading rotating edge will fall to one side of the straight-line path causing it to steer in that direction. Inertia will try to force the wheel in its original direction and friction from the surface will act with the inertia to force the wheel back to the upright position. You can see this wobble yourself. The wheel will quickly settle to a point of least resistance.

    The trick on a bike is that the wheel can be steered and the weight of the bike and its rider can be used to counter the upright tendency of the wheels. When leaving a turn, the handlebars are pushed in the direction of the turn allowing the upright tendency to act.

    Some people consider the trail of the forks to be important – and it is. It aids stability and allows the handling of the bike to be fine-tuned.

  7. The no bs bike thing, that can’t be right, because you can steer a motorcycle with no hands on the bars! You see cyclists doing it all the time…

    Maybe I haven’t understood it correctly but it doesn’t make sense

    • Yeah – you’re right you can. But if you look, when you lean left with your hands off the bars, which way does the bar turn?

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