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Traction Limit - Riding Skills Series
You've Passed The Traction Limit- Now What?

 Traction Limit

In the previous RSS (Dec. '06), we discussed how our sense of speed can be impaired by panic, causing us to think that we're entering a corner too fast. This often leads to the desperate-and false-sense that we need to stay hard on the brakes as we lean into the corner. In my eight years of instructing thousands of students of all ability levels on racetracks across the country, I can tell you without reservation that this panic situation causes more crashes than all others combined.

When done correctly, trail-braking ("trailing" the brake application as you enter the corner, making sure to ease off as your lean angle and cornering force increase) is a very useful tool, but it's one that should be wielded with caution. Like a razor-sharp knife, the line between success and failure is pretty thin, and the consequences can be costly. Visit www. sportrider.com/0703 for a link to more info on trail-braking.

While novice riders typically lose front-tire traction from excessive trail-braking, they also sometimes transfer too much weight forward by chopping the throttle (shutting it suddenly) midcorner. In either case, the sensation of losing front-tire traction is the same: The feedback usually communicated through the handlebars to your hands goes quiet, similar to the volume suddenly being turned down on your stereo. The next sensation is that of the bars turning inward as the contact patch loses traction and the bike falls inward.

Losing rear-tire traction is most often caused by too much throttle for a given lean angle. While expert riders have enough skill and experience to feel and control slides with throttle and lean-angle inputs, novice riders usually end up losing rear-tire traction suddenly and with little warning. The problem is that if the rider chops the throttle and the rear tire regains traction, the energy released from the momentum of the bike and rider's weight compressing the suspension completely and then springing back with full force can result in the dreaded highside, where the rider ends up catapulted high into the air, often with bone-crunching consequences upon landing.

Ironically, the solution to both situations is throttle application. In the front-tire situation, smoothly but quickly applying throttle relieves the load on the front tire by transferring weight to the rear, allowing the front tire to regain traction. In the rear-tire situation, backing off the throttle ever so slightly allows the tire to regain traction, while the continued throttle application maintains rear-tire rotation so that it continues to propel the bike forward, its gyroscopic effect helping keep the bike upright. Both these situations, however, happen quickly enough that the techniques must be done on reflex, and the only way to make such action instinctive is practice. Obviously, practicing these techniques on the pavement is extremely difficult (and could lead to expensive repair bills, both from the hospital and bike shop), so the best way to learn throttle control in these situations is to practice on the dirt with 125cc or smaller machines, where the consequences of a mistake are much less costly.

If you do happen to crash, the first thing to do is get away from the bike. You've probably seen videos of 125 and 250 Grand Prix riders hanging onto the bars as their bike slides to a halt so that they can pick the bike up and get back into the race, but getting one of your body parts trapped under the handlebar or other component is an easy way to lose it. Also, the bike has some serious kinetic energy built up; not only will it slide much farther than you, but should it begin tumbling, it will cause you even more serious injury if you become caught up in it. Try to relax and lay your body out as straight as possible to keep from tumbling. If you do tumble, you will more than likely end up violently whacking your appendages against the ground, often with bone-splintering results. While tumbling is a good way to avoid injury if you fall while walking or running, the energy built up traveling even as slowly as 30 mph will cause your arms and legs to fly outward uncontrollably. Sliding flat on the ground helps you scrub off that speed much more quickly, without the danger of exposing your limbs to additional impacts.

Once you are sliding on the ground, you need to resist the temptation to get up before you've stopped. It's very easy to become disoriented and think that you are sliding at a walking pace, when in reality you are still traveling at speed. Should you try to get up before you've stopped, nine times out of 10 you will end up tumbling because your legs will be taken out from under you. A good practice is to wait until you think you've stopped, then count to five-then make sure you don't have any major injuries before attempting to get on your feet.

Finally, the most beneficial thing you can do after a crash is be brutally honest with yourself about the cause and your possible contributions to it. It's all too easy to get defensive and, intentionally or not, place the blame on anyone or anything but yourself. From experience I can tell you that the riders who say they are never at fault for their crashes end up crashing for the same reasons again and again.

As an instructor, I've always taken it upon myself to study each crash as objectively as possible, identify the factors (there are typically several) and have everyone learn from the mistakes of others-mine included. You can learn from personal experience as well as that of others. And when it comes to crashing, I strongly suggest the latter.

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