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Old 05-25-2013, 01:43 AM   #511
Derbobs
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Body lean and pegs hardly work at all.

http://youtu.be/4PbmXxwKbmA
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Old 05-25-2013, 06:58 AM   #512
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You should return to your xbox where laws of physics don't apply

Quote:
Originally Posted by Scorpy View Post

You do not steer a bike once the wheels are gyroscopically stable which is a function of mass and rate of rotation of the wheel. The speed depends on the combination of both, so is difficult to define, but in my experience, anything less than 20 MPH needs a different technique.

All of the initiation of steering a bike is done intuitively with body weight. You may have heard the phrase 'You don't steer with your hands, you steer with your ass'. Not quite true. Everything above your ass makes the difference. That movement of your body translates into a moment arm that changes the relationship of your body's center of gravity (CoG) to the GoG of the bike. In simple terms, take a ruler in your left hand and hold it at the eight inch point losely between finger and thumb. Imagine this is where your ass is in relation to the bikes CoG. If you push the top of the ruler left or right, you cause the ruler to tip off center. Now instead of pushing, while the ruler is tilted, pull down at any point above your finger grip and the ruler will still tilt.

What you are doing by moving your body is inducing a vertical force between the vertical angle of the bike CoG and your body CoG and the force of gravity. This means that you also have a lateral difference between these angles, resolved as a lateral force.

THis lateral force acts as a pushing force on the top of the tyres and wheels, which are spinning fast enough to have gyroscopic properties. If you lean right, the force acts from the top of the tyre, pushing the top to the right. Because of the physics of gyroscopes, the force acts 90 degrees in the direction of rotation (forwards, unless you are doing something very wrong!), causing the front of the tyre to try to turn to the right.

As a result the twisting motion transmitted through the forks to the handlebars results in a force felt in the right grip pushing back. In an ideal situation you can do nothing and the turn continues, because the forces resolve themselves. (Ever ridden a pushbike with no hands?) but with changes in speed and small changes in body position or the radius of the turn, you have to 'counter' this force to allow for these changes by pushing back against the right bar.

One of the most important things to remember about all of this is *relax!
The designers have done all the hard work. Let the bike do the tuff stuff, just move your body to help it and don't worry about the bars!

This is the largest compilation of complete BULLSHIT that I have read on ADVrider.com.
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Old 05-25-2013, 09:49 AM   #513
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Quote:
Originally Posted by Scorpy View Post
.........THis lateral force acts as a pushing force on the top of the tyres and wheels, which are spinning fast enough to have gyroscopic properties. If you lean right, the force acts from the top of the tyre, pushing the top to the right. Because of the physics of gyroscopes, the force acts 90 degrees in the direction of rotation (forwards, unless you are doing something very wrong!), causing the front of the tyre to try to turn to the right.........
The front of the tire will try to turn to the right even when the bike is not moving and your feet are on the ground.

It will happen even if the bike would be moving backwards and the gyroscopic force applies on the rear of the tire.

The physics of gyroscopes helps, but is not everything: trail and caster are more influential, IMHO.
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Old 05-25-2013, 10:04 AM   #514
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This whole thread has so much misinformation on so many levels.

I reccommend that anyone who desires to know the forces acting on motorcycles should pick up the following books.....

Motorcycle Dynamics by Vittore Cosalter (my desktop reference at work)

Or

Motorcycle Handling and Chassis Design by Tony Foale. (sits right below Vittore on my desk)

Both are very valuable and contain all of the answers that people are looking for.

Tonys book may be hard to find as it is now out of print, and so far I have been unsuccessful in persuading him to reprint. But you can get an electronic coppy on his website.
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Old 05-25-2013, 11:50 AM   #515
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Quote:
Originally Posted by oldschoolsk8ter View Post
.......Motorcycle Dynamics by Vittore Cosalter (my desktop reference at work)
A fraction of the book can be read here:

http://books.google.com/books?id=rJT...page&q&f=false

A video about counter-steering that clarifies all possible confusions:

http://www.youtube.com/watch?v=PgUOOwnZcDU

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Old 05-26-2013, 02:15 AM   #516
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Quote:
Originally Posted by PT Rider View Post
In fact, we don't realize that the front end is always oscillating left-right-left-right and being brought back across center by the trail geometry built into the front end--if it ever runs straight, some road imperfection or breath of wind will start the movement again. ...
ALL: Hmmmm? This has not been my experience. I ride hands-free quite a bit. None of my bikes' front ends oscillate or wobble during hands-free riding even when crossing potholes, RR tracks, the odd bit of gravel, and the usual roadway imperfections. Not to derail the CS thread, but if one's handlebars are constantly oscillating, one might want to carefully inspect the bike for mechanical imperfections beyond specs? A wobbling front end is a sign that the bike is already unstable for some reason and not to be trusted to function as well as it should. The human body is not a very good steering dampener. Accurate steering requires a delicate touch. Any kind of front end wobble would interfer with steering touch and bike feedback. (No, none of my bikes have steering dampeners.)

Granted, a badly worn front tire will make the front end wobble slightly. If fitting a new front tire does not cure a slight wobble while riding hands-free, one might check for the proper tire and psi and then check to see what might be the matter with the bike.
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Old 05-26-2013, 03:39 AM   #517
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Originally Posted by IrishJohn View Post
I learned to ride a bycycle at age 8 or so and never had problems swerving or anything. I got a step through Honda 50 at 17 and never had a problem going around bends or swerving etc. I got a Kymco People 50 five years ago and never had a problem etc.
this proves men (and women) were programed to ride motorcycles. I rest my case.
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Old 05-26-2013, 03:42 AM   #518
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OK. It's late at nite and I might as well throw another log on this fire.

Sometimes it helps to use a worst-case scenario to illucidate a concept.

A very long time ago (mid 60's?) when I was so rank as a no-nothing noob that in retrospect I wonder how I ever survived, I often hit holes and road debris that I very much wished that I could avoid. And I rode slow and did not enjoy it very much trying to keep myself out of such trouble.

So, one day I am following an 'old' obviously much more experienced rider in heavy surburban traffic at about 30-35mph. Out from under the middle of the cage in front of us comes a huge pothole. Think open man-hole or worse. This is going to be a near instananious, very serious, unavoidable hit for this (Triumph with western bars) rider. The rider is right on the edge of hitting the hole due to near zero time from noticing the problem to moment of impact. With aplomb, he visciously yanks the handlebar to near full lock. I forget which side. The front wheel avoids the hole as does the rear. But the bike is so upset by this action that it looks like a sure crash is about to follow. Instead, the rider gives the handlebar another severe yank opposite to the first one. And the bike instantly straightens up and runs straight in lane on the other side of the hole. I was flat amazed to see this avoidance of hole and subsequent avoidence of steering crash. At the time, I thought that I had just witnessed a true miracle!
Natchurlly, traffic was heavy enough that I got a chance to ask the rider about all this when traffic stalled for red lights and back-ups. I didn't get an explanation of counter-steering way back then. But, I did get told that the bike would do such stuff if the rider was brave enough to learn how. I got told that the first yank was the easy part. The hard part was learning how to make the second, recovering, yank. I got told to leave the upper part of the body alone and not lean it, very much, with the bike if possible. And, most importantly, I was told to practice the moves in a safe place and work up to the bike's limits gently. So, I did.
FYI, back in the day, that was the second time that an experianced rider demo'd something for me, told me what he knew about riding, and saved my bacon. Much later, I learned why/how this worked and the process was called countersteering.
It might be helpful to some riders to go to a safe riding area and experiment, gently and progressively, with yanking (pushing...whatever) on the bars and bring steering inputs up to a level where a rider can be truly conscious of what is happening. The roadracers know exactly what it takes to get their bikes down to scratching a peg as quickly as possible and how to get it back up again and over onto the other peg as quickly as possible. Streetriders ought to be able to get a large percentage of that ability for themselves with some practice?
ymmv.

Sometimes I think that I oughta change my sig line to something like: If one is too scared to fall off as a matter of course, maybe one should give up bikes?
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Old 05-26-2013, 09:40 AM   #519
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Quote:
Originally Posted by ibafran View Post
ALL: Hmmmm? This has not been my experience. I ride hands-free quite a bit. None of my bikes' front ends oscillate or wobble during hands-free riding even when crossing potholes, RR tracks, the odd bit of gravel, and the usual roadway imperfections. Not to derail the CS thread, but if one's handlebars are constantly oscillating, one might want to carefully inspect the bike for mechanical imperfections beyond specs? A wobbling front end is a sign that the bike is already unstable for some reason and not to be trusted to function as well as it should. The human body is not a very good steering dampener. Accurate steering requires a delicate touch. Any kind of front end wobble would interfer with steering touch and bike feedback. (No, none of my bikes have steering dampeners.)

Granted, a badly worn front tire will make the front end wobble slightly. If fitting a new front tire does not cure a slight wobble while riding hands-free, one might check for the proper tire and psi and then check to see what might be the matter with the bike.
The weave isn't noticeable. If you locked your front wheel dead center while traveling at speed, the bike would fall over instead of continuing in a straight line
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Old 05-26-2013, 11:19 AM   #520
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Love your pothole example above, it brings up a good point/clarification about the before, during, and after effects of any handlebar movement (steering/countersteering). The importance of safe purposed practice cannot be overstated, because reading can be more easily misunderstood than the actual feedback you feel from your bike. Case in point - Push Right, go Right, well not exactly, that is only true in the end, in the begining (which can be very important in precise situations) when you push your right grip forward (turn the handlebars left) the bike will go LEFT! , mostly your wheels, until the lower half of your bike outruns the upper half creating a lean angle to the right and an eventual turn back to the right to get the wheels back under the bike and remain upright, or steet luge will occur (ouch). The amount is determined by your speed, bike geometry, and the amount you pushed right. Riders that have not been consious of Countersteering need to fully understand and practice all of the actions that take place. In most common situations the slight move (which can be as much as a few feet) in the OPPOSITE direction of the way you push will not be a problem, but it does exist and must be accounted for in the highest levels of riding and/or multi hazard precise avoidance. The importance where your tires are going to go initially becomes more important in the no time to respond pothole, and other examples. When avoiding small or too close to me hazards and no time (or room) to wait for the upper half of the bike to respond as the 2nd move, I will push right to THROW the wheels LEFT around the hazard, and then of course will turn right and regain upright position. Every situation is different and it all depends on where your wheels need to be NOW, and where you have room up ahead (left or right) to regain your upright position.
That should simplify everything ---- NOT!!! Go ride/practice with a purpose.

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Old 05-26-2013, 12:47 PM   #521
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Great point there, I often push left and dodge my wheels to the right. Push left, go right, then left, unless you push right before you go left.
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Old 05-26-2013, 01:40 PM   #522
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Writing or reading a theorem on this isn't doing any body any good , anymore than the term COUNTERSTEERING itself. It doesn't matter what it's called , there's only one way to turn a bike. Nobody reading this to learn will learn anything from reading , but they Will from actually RIDING.
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Old 05-26-2013, 02:38 PM   #523
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I learned a lot from reading
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Old 05-26-2013, 07:06 PM   #524
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Quote:
Originally Posted by joexr View Post
Writing or reading a theorem on this isn't doing any body any good , anymore than the term COUNTERSTEERING itself. It doesn't matter what it's called , there's only one way to turn a bike. Nobody reading this to learn will learn anything from reading , but they Will from actually RIDING.
In order to practice the right thing, you have to know what the right thing is. Knowing about countersteering will not, in itself, teach you how to ride a bike. But that knowledge can direct you on the correct path to learning how to ride a bike.

The place where this matters, in real life (and which has already been brought up several times in thsi thread) is that riders who do not actually *know* what they are doing, when in a stress or emergency situation, often panic and override their muscle memory to make an emergency maneuver. If they do not know about countersteering, and if they have not consciously practiced emergency maneuvers with that knowledge, they do, in real life, often do exactly the wrong thing, and steer themselves *into* the hazard instead of away from it. That's bad.

There is no reason to *not* know what you are doing, and good reason to know what you are doing and practice that. So those of us who are in this thread trying to educate people about what they are doing are acting in the interest of safety and knowledge. I don't know what the heck those arguing against it think they are doing.

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Old 05-26-2013, 07:29 PM   #525
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Originally Posted by PhilB View Post
In order to practice the right thing, you have to know what the right thing is. Knowing about countersteering will not, in itself, teach you how to ride a bike. But that knowledge can direct you on the correct path to learning how to ride a bike.

The place where this matters, in real life (and which has already been brought up several times in thsi thread) is that riders who do not actually *know* what they are doing, when in a stress or emergency situation, often panic and override their muscle memory to make an emergency maneuver. If they do not know about countersteering, and if they have not consciously practiced emergency maneuvers with that knowledge, they do, in real life, often do exactly the wrong thing, and steer themselves *into* the hazard instead of away from it. That's bad.

There is no reason to *not* know what you are doing, and good reason to know what you are doing and practice that. So those of us who are in this thread trying to educate people about what they are doing are acting in the interest of safety and knowledge. I don't know what the heck those arguing against it think they are doing.

PhilB
I'm not argueing against countersteering , professer. I'm saying you keyboard experts are confusing to the Newbs out there.They need practice and seat time , not a name to remember for a movement. Like I said earlier , there's only one way to turn a bike. They're already countersteering unless they fall down every ten feet.
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