Cornercraft: Staying Safer in the Swerves

Text: Robert Smith • Photography: RoadRUNNER Staff

The Hurt Report identified one of the most common single-vehicle motorcycle accidents as 'a slideout and fall due to overbraking or running wide on a curve due to excess speed or under-cornering.'

Barring unexpected intrusions, mechanical failure or changes in surface, you should never crash in a curve - as long as you take care of your vision and traction.

Vision:
That is, seeing where you're going. This remarkably simple concept often gets overlooked, especially in a series of inviting bends where the fun factor overrides common sense. When entering a turn, you should never ride faster than you can see to stop safely.

There are a number of things you can do to improve your vision in a bend:

  1. Look right through the bend. A common mistake beginner riders make is to focus on the road directly in front of them. In most circumstances, your peripheral vision will take care of this aspect. Make a point of turning your head to look straight through the curve. Following the simple idea that you 'go where you look,' perhaps no single factor will improve your cornering than looking through the whole curve ahead. Try it and you'll see.

    Next time you're watching motorcycle road racing on TV, watch the riders' heads and eyes…
  2. Look for the vanishing point: If you can't see right through a curve, look for the point where the outside of the road disappears behind the obstacle (trees, cliffs, buildings, whatever). This is the 'vanishing point.' If it's moving toward you, the curve is tightening, and you may want to consider slowing. If it's moving away, the curve is opening up.
  3. Position yourself on the road for the best vision. Before a lefthander, move to the right of your lane. Before a righthander, move to the left. This will give you maximum vision through the bend. But make sure you take surface, traffic and other road conditions into account.

    Traction:
    I'm not going to talk about how small the road surface contact patch is on a motorcycle tire; you already know that. But how you ride makes a big difference regarding the effectiveness of that contact patch. Traction is affected by surface conditions, tire conditions, and the external forces applied to the contact patch.

Let's say when your bike is rolling along at a steady speed in a straight line you have 100 percent traction. Braking or accelerating will reduce the available traction by applying lateral forces to the contact patch between the rubber and the road, and so will cornering. Any kind of skid - whether a start-line burnout, a rear-brake lockup, or a low-side slide - means you've used up all your traction, and on the road, total loss of traction is usually a bad thing.

So let's say you're cornering and you've used up 50 percent of your available traction to contain the centrifugal force that wants to push you out of the curve. If you apply the brakes or accelerate, you're using up more of your traction, to the point where, if you use up the remaining 50 percent, you're in a slide. So from a safety standpoint, it's best to separate braking from cornering. Hurt noted that many single-vehicle motorcycle crashes in curves were a result of 'overbraking.' The same brake loading applied on a straight road may well have been perfectly safe.

A question I used to ask students: 'When is the best time to brake in a curve?' The right answer in most circumstances is before you get there…

Vision and traction together:
So, putting together these two concepts - getting the best sightline through the curve, and maximizing traction - gives a basic outline for how to corner safely:

  1. Stay wide before entering the curve, so you can see as much as possible of the exit.
  2. Adjust your speed using brakes and/or engine braking before entering the curve.
  3. This implies you will enter the curve late and apex late.
  4. Entering and apexing late means your curve radius increases as you go through the curve, allowing you to safely accelerate through and out of the curve.
  5. You'll also be better positioned on the road to enter the next curve,
  6. And if you do enter the bend too fast, you have room to run wide on the exit.

How does this look in practice?

Just a couple of final points. This is not meant to be a racing technique, or necessarily the fastest way through a series of curves; but adjusting your speed before entering a bend, and maximizing your sightlines will give you an extra margin of safety in most situations. Always be aware of road conditions (traffic, debris, surface, weather, etc), and above all, ride within your personal comfort level. If you're in a group, ride your own ride; don't let a faster rider 'tow' you through the curves - just because they're faster doesn't mean they're safer.

When riding a motorcycle, Safety is your top priority.

Ride safe!