Proficient Motorcycling - David L. Hough

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countersteering to mean momentarily steering the contact patch opposite to the direction we want the bike to roll. Let’s be clear that countersteering isn’t a matter of whether the bars are turned left of center or right of center, or whether that takes a push or a pull, whether the bike is upright or leaned over, or whether speed is fast or slow. Whatever the position of the bike or front wheel, you momentarily steer the front wheel opposite the way you want the bike to roll.

      For example, if the motorcycle is leaned over in a tight left turn and then a crosswind pushes it over a little too far, momentarily pulling on the left grip will keep it from rolling over farther. Is that still countersteering, even though the front wheel is pointed to the left of center in a left turn? Sure. Countersteering is a momentary, dynamic input, not the direction the front wheel happens to be pointed toward at the moment. Or let’s say you are leaned over into a left turn and it’s time to lift the bike up and exit the corner. Momentarily steering the front wheel slightly more toward the curve (by pressing the grips more toward the right) forces the bike to roll more upright. The momentary press on the grip to roll the bike vertical is countersteering. You can’t determine countersteering from a still photograph because it’s a dynamic motion.

       Push Steering

      If you’re still a little confused about this countersteering business, I suggest a little experiment. The simplest way to describe countersteering is to push on the right grip to turn right or push on the left grip to turn left. Take your bike out for a spin; get up to 35 mph or so on a straight, vacant road; and consciously push lightly on the left grip. The bike will lean over slightly left and move over toward the left side of the lane. Now, push on the right grip. The bike will lean slightly right and steer back toward the right side of the lane.

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       In this situation, the rider is momentarily steering the front wheel more toward the left to roll the bike more upright, but the wheel is still pointed toward the curve.

      This isn’t something new because it’s how everyone steers motorcycles, whether they realize it or not. Lots of riders concentrate on body English such as knee or foot pressure, unaware that the important input is through the hands. Accurate cornering is much easier once you realize that the primary input is through the grips. But once you’ve experimented with push steering, it’s time to move on. Different machines and different situations provide different feedback to the grips when leaned over in a corner. So we need to understand countersteering as more than simply pushing on the low grip.

       Out-Tracking

      When you countersteer, it may seem as if pressure on the grip pushes the bike over without actually pivoting the front wheel. Does the front end actually pivot away from center as the bike leans over into a curve? Yes. The movement is slight, but if the front end isn’t free to pivot in the steering head, the motorcycle can’t be balanced or turned.

      If you could watch a slow-motion video of a motorcycle running through a puddle of paint and then making a turn, you would see that the front tire momentarily tracks toward the outside during the initial countersteer, then eases back toward the direction of turn. In slow-speed turns, the front tire generally tracks outside the rear tire.

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       When the rider countersteers, the front wheel momentarily out-tracks opposite the intended direction of the turn, then returns to center as the motorcycle leans over.

      If you’d like a good example of out-tracking, record some motorcycle road race footage, and play it back in slow motion. In those shots where the camera is looking back down the straight toward a corner, you can see the lean angle of the bikes head-on. If you mentally plot the path of the motorcycle’s center of mass, you’ll see that the bottom of the front tire out-tracks, even arcing over onto the rumble strips as the rider uses every last inch of pavement to get the bike leaned.

       Coning

      While your bike is leaned over in a curve, you might wonder why the bike continues to turn even though the front end seems to be pointed straight ahead. Part of the reason is that the front wheel really is pointed slightly toward the curve. The other part of the reason is called coning. To understand the concept of coning, let’s consider the shape of the front tire where it meets the road surface.

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       The motorcycle pictured above is in a straight line, approaching the turn-in point.

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       As the rider countersteers, the front wheel actually tracks away from the intended direction of turn.

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       With the motorcycle leaned, the front wheel recenters and then steers toward the turn.

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       When the wheel is leaned into a turn, the flexible tire forms a contact ring that is conical in shape, similar to the shape of a foam coffee cup on its side.

      Although we can see that the top of an inflated tire forms a rounded shape, we have to imagine that the tire momentarily gets flattened where it contacts the ground at the CP. And we also know that the tire CP isn’t really a single point but rather a continuous ring around the tread. It’s important to recognize that with the bike leaned over into a turn, this contact ring forms a conical shape, similar to a foam coffee cup on its side.

      If you nudge the cup forward, it wants to roll in a circle because the circumference at the closed end is smaller than the circumference at the open end. If you stick a toothpick through the center of the cup bottom, the toothpick will point approximately at the center of the circle. A motorcycle tire responds similarly when the bike is leaned over, with the inside of the tire contact surface covering less distance than the outside. So when leaned, a motorcycle wheel wants to roll in a circle, with the axle pointed more or less at the center of the turn. In a very tight turn, the axle may actually point at a center that’s below the surface of the ground.

       Fast Flicks

      The more muscle you put into countersteering, the harder the front tire will push to roll the bike into a lean, and the quicker it will roll (up to the limit of traction, of course). The longer you hold pressure on the grip, the farther over the bike will roll. Those are key points to remember when riding a twisty road where you need to flick the bike left-right-left in a series of turns. Remember, it may take a half second to get the bike rolled upright from a tight turn and another half second to get it leaned over the other way before it changes direction.

      Is it possible to muscle the handlebars hard enough to snap the tires loose? Yes. You may have seen this in a road race, where a bike suddenly jumps into a heart-stopping wiggle in the middle of an S-curve, or the front tire loses its grip and the bike crashes off on a tangent. In an aggressive S-turn, the rider needs to counteract the roll when the bike is leaned to the desired angle, and that demands some traction.

      A motorcycle rolls around its center of mass (CoM) without a lot of resistance but resists being pushed up, down, or sideways. That’s why a bike speeding over a lumpy bridge on the Isle of Man can get airborne. The bike’s mass wants to keep going straight ahead, even as the ground drops away beneath the tires.

      Even if you aren’t flying over a steep bridge, the bike’s inertia will momentarily resist

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