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cornhuskxr
Mon Sep 11th, 2006, 07:35 PM
Slow, Look, Lean and Roll
Oct 16 '01

The Bottom Line Slow Look, Lean and Roll. A simple mantra, taught to students just learning to ride a motorcycle, meditating my way through the twisties, and making me a better rider.

Professor Harry Hurt, of the University of California, completed and published a study of motorcycle accidents around 1981. Hurt and his staff personally investigated 900 motorcycle accidents in the Los Angeles area. Additionally, they investigated 3600 traffic accident reports from the same area. While the final study and the appendix come to about 800 pages, the summary of the report is what has been quoted most over the years. The report has the long name of: Motorcycle Accident Cause Factors and Identification of Countermeasures, Volume 1: Technical Report, Hurt, H.H., Ouellet, J.V. and Thom, D.R., Traffic Safety Center, University of Southern California, Los Angeles, California 90007, Contract No. DOT HS-5-01160, January 1981 (Final Report)

However, it has come to be known as simply the Hurt Report.

I have a friend coming over for a ride today and I am going to show him some of the nicer roads in my area. Those roads have curves.

I was thinking about that ride the other day, as I puttered around in my shop, going over the Bandit.. I kept thinking about what Hurt discovered in his report. How riders involved in single vehicle accidents mess up turns. I also thought about how simple cornering is and how overly complex we tend to make it.

The Hurt report found that:

“4. In single vehicle accidents, motorcycle rider error was present as the accident precipitating factor in about two-thirds of the cases, with the typical error being a slideout and fall due to overbraking or running wide on a curve due to excess speed or under-cornering.”

“28. Motorcycle riders in these accidents showed significant collision avoidance problems. Most riders would overbrake and skid the rear wheel, and underbrake the front wheel greatly reducing collision avoidance deceleration. The ability to countersteer and swerve was essentially absent.”

A summary of the summary suggests that too many of us simply don’t know how to corner, or are lacking in some aspect of cornering skill.

The curves draw us, they tempt us, they are the place we really belong on a bike. Riding a bike though the curves is akin to flying an airplane through the canyons. Curvy roads draw all kinds of riders, especially those on sportbikes. These roads point to the essential nature of motorcycling. They distill riding down to the four simple acts that make up all of what riding is about. That being straight line riding, shifting, turning and braking. Everything comes together when we hit the twisties.

The twisties are also the court by which our riding skills are judged. Corner after corner our skills are put to the test and a verdict rendered. So, why do we fail with such regularity? Every one of you reading this remembers a curve you messed up, one you didn’t ride well. I remember them. I remember not being settled, not having the right line, not being ready for the next turn, just not riding as well as I know I could. Over time, I have improved, as I’m sure most of you have, but I still have a long way to go. My bad habits sometimes crawl from under my riding bed, ready to scare me if they can. How do I turn on the lights, and keep those monsters under the bed?

Do I take track days, read books, ride with faster riders, go racing? I could. All of those things do have the potential of improving my control of the bike. All of those things may improve my riding skills, settle me in the twisties, and make me a better, smoother and safer rider. All these can also make me faster too, but that is secondary to me. With smooth comes fast, not the other way around.

I can throw my efforts in to track days and riding schools, I can pour over the books, learning to twist my wrist just right, I can follow better riders, learning their lines on my favorite roads or...

I can simply Slow, Look, Lean and Roll.

Whether you are a brand new rider learning this in the MSF basic rider course or one of the Bostrom boys, ripping up Laguna, it takes the same thing for every curve.

Let’s look at what Slow, Look, Lean and Roll is about.

Slow is about entry speed. Entry speed is the first part of the equation. It is tied directly to the last part. We must Slow to a speed that allows us to negotiate the turn. In the findings of Hurt and his staff, riders crash in turns due to excess speed in cornering. Since braking in a turn isn’t always the best choice (you can‘t use the same traction for turning and braking -- something has to give), choosing the proper entry speed for a turn is crucial. If we choose the proper entry speed, we don’t need to brake, we can concentrate on the corner and move on to the next step in the process.

Look through the curve. My worst habit, one that I work on all the time, is that I don’t look far enough through the curve. In England and Europe, they teach new riders a concept called the Vanishing Point. Riders learn to concentrate on the farthest point they can see, keeping their focus and attention there, letting their peripheral vision pick up the things that are close to the bike. In short, they look up and ahead, concentrating on where they want to go and not where they are. As Bill, an experienced rider and track teacher tells me, most riders have this problem. They look down at the blurry fast pavement and draw their attention away from where it belongs.

If you ride for the Vanishing Point, if you never ride so fast that you can’t stop in the distance you can see, you have it made. You won’t be surprised by the corner. You won’t end up using the brakes or rolling off the throttle and you will ride a better line.

Leaning is what corners are about. In order to corner well a single track motorcycle has to lean. While there is still debate over counter-steering vs. body-steering, the simple fact is the quicker and smoother we can get the bike leaned over the faster we get on with the business of turning the thing. I’m a counter-steering advocate. Handlebar inputs are one of the best ways to make a motorcycle lean, or stand up after a turn. By simply pressing on the bar in the direction we want to go, we initiate lean. The bike “falls” inward towards the turn. When we reach the right lean, we ease up on the pressure, the bike’s steering geometry balances and we are in a turn. To stand the bike back up after the turn smoothly and quickly, we press on the outside grip, the bike “falls” up.
We ease up on the pressure when the bike is vertical and ride on. So, no matter your own leaning technique (I will always favor counter-steering, no matter how complex the physics discussion are about how it works, the simple fact is that it simply works), the more deliberate and smooth it is, the better your cornering.

Roll on the throttle and you will have a better corner. Just a slight roll on the throttle throughout the turn causes the bike
to stabilize on it’s suspension and transfers weight to the rear wheel. The bike ends up in a steady state of constant acceleration throughout the turn. This makes for a better turn. Remember I said that the first part of this ties to the last? If your entry speed was too high, you won’t be able to roll on the throttle.

So, what can go wrong? If you don’t Slow your entry speed will be too high. If you don’t Look through the turn, you won’t see where you are going. You will end up making slight, twitchy, unsure, unstable mid-course corrections for every little blurry ripple you see three feet in front of your bike. If you don’t Lean, you can’t really turn. If you don’t Lean over far enough, you can run wide. If you don’t Roll, the bike isn’t as stable and it won’t hold the line you want.

It’s simple. It’s taught to new riders but, it applies to every single corner we ride It doesn’t matter if you are a MSF newbie rider just out of class with their completion card or one of the Bostrom boys. The corners don’t change, just the skill level of
the riders.

I took a ride shortly after taking my MSF basic rider course in preparation for becoming an instructor. The MSF isn’t the be all, end all of motorcycle teaching, it’s just the beginning. In this part though, they really have it right. As I rode over the following weeks, I concentrated on the Perfect Ride. That ride concentrated on cornering and, this 26 year rider had developed some bad habits. Every corner I came to, it was Slow, Look, Lean and Roll.

Slow, Look, Lean and Roll.

Slow Look, Lean and Roll.

A simple mantra, taught to students just learning to ride a motorcycle, meditating my way through the twisties, and making me a better rider.