All motorcycles are built to be inherently stable i.e. they will tend to travel in a straight line if undisturbed. Even if they are disturbed by a slight turn of the handlebar, they will tend to return to the straight and upright position. This is made possible by the geometry of the motorcycle’s construction. The front wheel is inclined forwards at an angle (called the ‘Rake’). The front tyre’s contact patch falls below the front-wheel’s axle while a line extending and following the Rake angle meets the ground a little further ahead of the contact patch. This distance between the contact patch and the extended rake line is called Trail. Trail is primarily responsible for a bike’s straight line stability. Of course too much stability (vis-à-vis a large trail as in cruisers for example) leads to sluggish maneuverability. Motorcycle design is therefore always based on the targeted end use of the bike.

At very slow speeds we steer a motorcycle by turning the handlebar in the direction we wish to go. We can only do that at speeds of less than about 10kmph. At any higher speed, we do the exact opposite, whether we realize it or not. For example, assuming we want to turn to the right, we actually TRY to turn the handlebar left. This results in the front wheel leaning to the right and, as a result of the lean of the wheel, a turn to the right. This is counter-steering. No matter how slight, if your front wheel deviates from a straight path your motorcycle will begin to lean in the opposite direction. You can observe it at a complete stop. Just turn your handlebars in one direction and you will see that your bike leans in the opposite direction as a result. The ONLY WAY to turn a motorcycle that is moving faster than you can walk is by leaning it.

There is another, more powerful, reason that the lean is translated into a turn - Camber Thrust. Unlike car tires, your motorcycle rides on tires that are rounded instead of flat from side to side. When you are riding vertically the contact patch is right in the middle of the tire, at its farthest point from the hub of the wheel. When you are leaning, you are riding on a part of the tyre that is closer to the hub of the wheel. The farthest parts of the tyre from the hub of the wheel are TURNING FASTER than any part closer to that hub. Thus, when you are leaning, the outside edge of the contact patch is moving faster than is the inside edge. To make it easier to understand this, imagine a typical motorcycle tyre profile as two truncated cones joined at their bigger flat faces. As the tyre leans to one side, just one cone comes into contact with the road. And as the bigger end of the cone lies towards the outside of the turn and the smaller end towards the inside, the outside edge Your browser may not support display of this image. has to travel a longer radius and so travels faster than the smaller end thus making the cone (and so the tyre) follow a circular track.

Counter-steering is a much more effective way to steer a motorcycle than shifting body weight. If something suddenly enters your path and there is no way to stop in time, counter-steering may save your life. The trick is to look past the object to your escape route, and to quickly counter-steer in the proper direction. Imagine yourself cruising down the highway on a beautiful bright day. Suddenly you see (your worst nightmare: a large pothole, a dog, a rock or whatever) in the road, covering the right two-thirds of your lane. If you do not consciously understand and use counter-steering, you will probably attempt to steer left like you would on a slow moving bicycle or in a car where you steer left to go left. To do that you will push on the right side of your handlebar and this will steer you directly into the object. The correct action here would be to push on the left side of the bar (as if you are steering to the right i.e. towards the obstacle instead of away from it) and steer away from the obstacle. That is why we call it counter-steering (since we steer in a direction counter to what we feel is the normal one). So remember: "Push left to turn left. Push right to turn right." Like any safety technique, it only works if you practice it. Unless the action is second nature, you will return to your old habits during an emergency. Riders who do not practice counter-steering, will try to turn away from the object, which just brings them closer to it!