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Really nailing a corner is one of the more thrilling experiences you can have on a motorcycle; but getting it wrong can be one of the more painful.

The best approach to understanding cornering is "divide and conquer." You need to divide a corner into four main points: the braking point, turn-in point, apex and exit.

Entering Buttonwillow's decreasing-radius hairpin corner, Yamaha R1-LE-mounted Jim O'Connor takes a wider entrance than MV Agusta-mounted Lance Holst, who is demonstrating what not to do and why.

Proper cornering technique needs to begin with hitting the turn-in point at your desired speed. If you're hard on the brakes, standing the bike on its nose with the rear tire in the air or slewing side to side, you're virtually assured of, at best, blowing the corner or, if you're not so lucky, tasting the asphalt. So begin by braking early and comfortably setting your speed for your corner turn-in point.

The turn-in point and the apex are the most critical aspects of a corner. Turn-in points are initially judged intuitively by using your vision to determine approximately where you should begin your steering input. As you become more familiar with the road or racetrack you're riding and your speed comes up, the need for precise reference points increases.

As with any aspect of riding, you want your vision to be at least one step ahead of the bike. Approaching your turn-in point, keep track of it with your peripheral vision, but the center of your vision should be focused toward the apex. Approaching the apex, look ahead to the corner exit and down the track. Smoothly scan your vision forward in constant motion, not stopping to fixate point to point. The moment your vision fixates, you begin to get behind what the bike is doing on the track.

The corner exit shows the benefits of O'Connor's later turn-in and later apex as he has his bike picked up and accelerating sooner while hapless Holst is still finishing off the corner to get the mighty MV pointed down the straight before any meaningful acceleration can be applied. The lesson here is that while a tight entrance may close up the gap early on, Jammin' Jim's late apex gives him several times that advantage at the exit.

As the turn-in point approaches, begin easing off the brakes gradually as the bike is leaned into the corner. As the bike is leaned further into the corner, continue to transition smoothly off the brakes, making sure to be off the brakes entirely before maximum lean is reached. The bike's increasing lean angle and resulting cornering force mean that there is no additional traction left for braking. As maximum lean is approached, smoothly apply a slight amount of neutral throttle; this isn't accelerating, but instead balancing the chassis by transitioning weight off the heavily loaded front tire to balance it with the rear. At neutral throttle, you're allowing the tires to share the side grip load more equally, greatly reducing the risk of overpowering available front-tire traction. This middle portion of the corner is where you should do the majority of the turning, getting the bike pointed through the turn, so that by the time you approach the apex you're able to pick the bike up slightly (say 10 to 15 degrees from maximum lean) and begin smoothly opening the throttle to start accelerating. Do not attempt to accelerate before lifting the bike up from maximum lean.

It's important to realize that the precision of the proper line varies with speed. At a relaxed street pace, placing your bike nearly anywhere in your lane can be an acceptable line. But as your speed increases, your margin of error lessens and the acceptable line becomes progressively narrower. At a race-winning pace, the proper line on critical portions of the track is squeezed to mere inches, or perhaps even fractions of an inch, wide.

A specific turn-in point is where that critical precision begins, because where you begin your turn determines your apex and resulting exit of the corner. It's best to remember that our instincts (especially under stressful or panic situations) tend to cause us to turn in too early, which, in turn, forces an early apex that usually results in a wide exit point. The options available at this point are all bad: either scrub speed, increase lean angle or run wide. Reducing your speed can be accomplished by either smoothly rolling off the throttle or feathering the brakes, but both risk overcoming the available traction. Increasing lean angle after the apex is disconcerting for most riders, since they're already leaning as far as they're comfortable-and whether they're near the limit of traction or not, they perceive that they are. Running wide can put you into the dirt or grass in the best of circumstances or into the path of oncoming traffic in the worst. The lesson to learn is not to turn in too early. For instance: If you run out of pavement at the exit, you need to turn in and apex later. If you find yourself exiting the corner in the center of the track, you can either increase your speed or turn in and apex earlier. Study the corner diagram for a clear illustration of this.

Here's an illustration for cornering techniques

The physics of cornering can be summed up in terms of corner radius (the measurement of how tight it is), corner speed and lean angle. For a given corner radius, increasing corner speed requires a larger lean angle. As a corner tightens up, we're forced to either reduce corner speed or increase lean angle. Maximum lean angle is determined by either the cornering clearance of the bike or the traction of the tires. Hanging your body off to the inside of the bike shifts the combined bike/rider center of mass to the inside, which allows the bike to be more upright for a given corner speed. This, in turn, allows you to increase your speed and use the additional lean angle you've gained. The fastest riders get their speed from maximizing the physics involved in cornering.

Many corners are constant radius, meaning that the radius remains unchanged throughout, but there are increasing-radius and decreasing-radius turns as well. An increasing-radius corner opens up as you travel through it, which tends to inspire confidence because you have more track available on the exit. Decreasing-radius corners are just the opposite, in that they tighten up and rob confidence. There are factors other than radius that are critical to understanding corners as well: elevation and camber. An increase in elevation helps slow the bike, which tightens the cornering line, while dropping elevation has the opposite effect. Camber is how we define the banking or lack of banking in the cross section of pavement. Positive camber is the presence of banking, which slightly increases the available lean angle and traction and assists in turning the bike. Negative camber pavement slopes away, which decreases traction, robs us of available lean angle and encourages the bike to run wide.

On any track or section of road, there are corners that inspire confidence and those that make riders uneasy. For corners that make you uneasy, study them carefully in terms of radius, camber and the available traction dictated by the surface and smoothness of the asphalt itself. Breaking it down helps you not only understand the corner better, but also allows you to come up with a different way to approach the corner that makes you more comfortable.

Some riders assume that the fastest way around every corner is to enter as wide as possible, hit the apex at the center of the corner, and use every inch of pavement at the exit, essentially scribing as wide an arc as possible which, in theory, allows the highest corner speed for a given lean angle. This might be true if not for the fact that a tire using all its available traction for cornering force, or side grip, has no additional traction available for braking or acceleration. Leaning over at the limit of adhesion is also a risky proposition, depending too much on the available traction from a very small contact patch.

In the middle of the hairpin, O'Connor uses a later apex, while Holst, who closed up the gap slightly by taking a tighter line and covering less distance, has apexed earlier, which will keep him leaned over longer.

If your goal is quicker lap times, the length of the straight following the corner determines which type of apex to use. Think of corners that lead onto long straights as "drive" corners, and turns that lead to short straights or other corners as "momentum" corners. Momentum corners are best approached with wide, sweeping lines that maximize midcorner speed and conserve momentum. Drive corners which lead onto long straights reward late apexes that allow riders to get their turning done early, in order to begin picking the bike up off the edge of the tire and accelerating sooner.

The best option depends on your strengths as a rider, but more importantly, the strengths of your bike. What a Kawasaki ZX-10R does best, for instance, is accelerate. It turns the best lap times by late-apexing corners leading onto the straights, in effect compressing the corners and lengthening the straights. A rider maximizing his midcorner speed might arrive at the corner exit before the rider who slows the bike midcorner to get his bike pointed, but the late-apex rider will exit the corner with, say, two to three more miles per hour, which is an advantage held all the way down the following straight. The result is that Mr. Late Apex soon overtakes Mr. Midcorner Speed and extends that advantage all the way to the next braking point. On the other hand, a bike that doesn't accelerate as strongly-for instance, the Kawasaki 650R twin that Editor Kunitsugu raced at Daytona-can't afford to slow as much midcorner as a literbike, so maximizing midcorner speed in order to maintain momentum off the corner is paramount.