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terbang
9th March 2006, 20:56
I know this is a subject that has been more than likely to have been kicked to bits in the past but it is allways a good one to revisit and we do have a constant stream of new riders. So I am posting an article that was sent to me by a mate of mine in USA that I quite liked (hence the yank terminology) to stirr up some good debate..Enjoy..

Let’s first examine the proper way to make a motorcycle corner. I would say any thing under the speed of 15 mph you would turn the handle bars in the direction you want to go. That is turn right, go right, turn left, and go left.
Anything above 15 mph you will use counter steering. I’m sure there are a few out there (probably a lot more than a few) that believe that in order to turn a motorcycle you must lean into the turn. In other words, Lean your upper body to the right and the bike will go to the right. This is true in a sense, but not the easiest and most effective way to turn. Counter steering is a proven way to negotiate curves. Basically it is Press right go right, press left go left. What I mean about press is to press down on the hand grip in the direction you want to go. Do not press outwards in the direction you want to go. Next time your on your bike give it a shot, just press down on the right hand grip and your bike will lean to the right. Keep your body relaxed, with your elbows slightly bent. No need to hyperextend your arm downwards, unless you want to drag a knee. Don’t worry about your upper body, like the old saying Shi*t happens so does lean, your body will follow. Do not fight the lean by leaning the opposite way either. Just press and everything else will fall into place. If you want to turn/lean more all you have to do is press more on the hand grip in that direction. Now that we examined the easiest way to make the motorcycle corner lets look at the proper procedure to safely negotiate curves.

The procedure is Slow, Look, Press, and Roll. The First step to any curve is slow, slow down your speed. Second is to Look where you want to go, Press (counter steer) in the direction you want to go, and Roll on the throttle.

Slow: Slow down so that you can see hazards coming up in the curve, so that you don’t ride outside of your limits, and it also allows you to roll on the throttle.

Look: The key to motorcycling is to look where you want to go. It’s just that simple. Look right go right, Look left go left, Look behind you and you can make a u-turn in your two car driveway easily. I hear some riders that have gone down tell me that while in a curve they looked to the outside of the curve and they flew off the road. Some tell me about looking down at the ground or curb and freaking out and grabbed the brakes or hit the curb and wrecked. Head and eyes are the key. So in a curve look level with the horizon as far as you can into the curve. Trust your eyes; your peripheral vision will catch everything around you.

Press: Just use the counter steering method as described above.

Roll: Roll? Get off the bike and roll on the ground? No, Roll on the throttle. Give it gas or maintain a steady speed in a curve. Do not role on the gas like a fool, so that you ride outside the curve and get yourself hurt. Rolling on the gas stabilizes the motorcycle in a curve. I’m not going to get technical on the physics of it, it just works. While in a curve if you ever rolled off the gas (decelerate) you felt the bike get jumpy. That’s because the front end is no longer stable. So if you slowed down enough, as in the first step, you will not have a problem rolling on the throttle. If it is a blind corner and the corner turns out to be a decreasing radius turn all you need to do is press more. This shouldn’t be a problem for you, especially if you knew it was a blind curve and took the correct precautions before the turn. We will get into slowing in a curve and braking in a curve at a later date.

Also use the outside insides outside path of travel in every curve. It is the straightest line thru a curve (not needing excessive lean angles) and it also allows you to see farther thru the curve.

Skyryder
15th March 2006, 18:28
Good advice but too long for here. Something to do with short attention span syndrome.

Skyryder

duckaddict
15th March 2006, 22:16
thks terbang :Punk:

Lazy7
15th March 2006, 22:25
i think its probably one of those things that you do without thinking...

i was riding a bike for about a year before anybody told me about counter steering, then shortly after that i realised i was doing it anyway.

especially in a change of direction situation a quick right left movement, giving the handlebars a quick nudges gets the bike swinging over heaps quicker than you would if you just tried moving your weight...

Jantar
15th March 2006, 22:49
There have been a number of similar articles published in various motorbike magazines over the years, and I must admit that I've been tempted to research as many of them as I can find and incorporate the various idea into one overall philosophy.

Cornering isn't as simple as turn right to go right up to a certain speed, then press right to turn right at higher speeds.

Like in aviation, motorcycles have a number of critical speeds, eg.

Minimum sustainable speed (Vs): This is like an aircrafts stalling speed. There is a minimum speed below which your bike will not balance itself. The speed will differ from bike to bike, but generally the lighter the bike/rider combination and the larger diameter the wheels the lower the minimum speed. At lower speeds the rider has to assist with balance by moving body weight, turning the bars towards imbalance etc. For most bikes this minimum sustainable speed is just slower than idle speed in first gear. (Maybe the bike manufactirers have engineers who do know what they are doing). Try controlled cornering at a lower speed and you are likely to crash.

Minimum normal speed (Vc): For speeds between Vs and Vc it is necessary to lean in the direction of the turn using your body weight and turn the handle bars in the direction of turn. Again, this speed will differ from bike to bike, and will be determined by the wheel diameter and rolling inertia, and the bike/riders weight and height to the center of gravity. At speeds higher than Vc counter steering is the best way to control the rate of turn. To find this speed for your own bike find a tightish corner, but one that you could get around safely at around 60 kmh. Enter the corner at around 20 kmh with a light grip on the handlebars and accelerate through the corner. Watch to see at what speed the bars straighten themselves without any input from you. This is your bikes natural Vc

Maximum design speed (Vne). This is maximum speed for which the designers expect the bike to remain controllable. It will dependon frame design, tyre speed rating, suspension travel and settings, aerodynamics etc. Many years ago manufacturers used to list a max speed in their performance data. Many testers would slag them off by saying that the max speed was unobtainable. But in fact the manufacturers weren't saying that the bike would necessarily get to such a speed, rather they were saying that was the speed that should never be exceeded. Sometimes they would claim that the bike had been tested at a particular speed, but then they were opening themselves to unfavourable test reports.

Happy experimenting. :hitcher:

marty
16th March 2006, 06:24
mmmmm vne.

Fishy
16th March 2006, 07:46
No need to hyperextend your arm downwards, unless you want to drag a knee. [/I]

Haha this guy obviously doesn't know anything about anatomy terminology. If you were to (Hyper) extend your arm downwards, this would mean your arm would be reaching towards your pillion footpeg. (if moving the shoulder joint).