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Discussion Starter · #1 ·
I have a physics question I don't even know how to begin to answer. Maybe one of you can help.

Of course counter steering is used to initial a turn and to get the bike to lean. On the other hand, I KNOW that CONTINUING to counter steer, even with the same amount of effort or handle bar steering angle (NOT the same lean angle), will make the bike fall down and go boom. In fact, I am more than half convinced you can counter steer a bike flat into the ground in well under half a second.

So, here is the question: If you quickly pushed one handgrip forward 1" and left it there (against all survival instincts), would the bike fall over and hit the pavement in less than ONE front tire rotation?

It sure feels that fast, but does anyone know the math to prove me right or wrong?

Opinions are certainly welcome, but no fair calling me names for asking a question or having an opinion. If you ain't gots da math, yo opinion, while interestin', ain't no better dan mine's. :lol:
 

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Why don't you try it and let us know ???

:lol:


:joke:

... actually discussions such as this are good. I'm reading "countersteering" in Wikipedia ... interesting !!!
 

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So, here is the question: If you quickly pushed one handgrip forward 1" and left it there (against all survival instincts), would the bike fall over and hit the pavement in less than ONE front tire rotation?
No
 

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Counter steering is a lay term for gyroscopic precession.. Apply force to a stabilized gyroscope and it reacts with an equal force90 degrees to the spin along the axle
 

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You mean like this? He is going left and his front wheel is pointing right. It worked in the movie Cars too.
 

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You mean like this? He is going left and his front wheel is pointing right. It worked in the movie Cars too.
This is not countersteering as applied to conventional riding because he is in a sliding (powerslide) situation. The wikipedia link is the best explanation that I have seen. In a left turn, the actual right rotation of the steering axis is only momentary then it becomes a left rotation once the lean is initiated even though forward pressure on the left handlebar is maintained throughout the curve.

Jeff...
 

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Discussion Starter · #9 ·
Why don't you try it and let us know ???

:lol:


:joke:

... actually discussions such as this are good. I'm reading "countersteering" in Wikipedia ... interesting !!!
Yes. I have! About fell right over. That's why I'm interested. Supposedly, at least the way most teachers explain it, you KEEP pressure forward on the inside bar. This is not true. Try it. Carefully. If you KEEP pressing forward, you will KEEP leaning more and more and it happens very quickly. Don't say I didn't warn you.

Also, I know, from doing Ride Like a Pro, that the front wheel ENDS UP pointed into the curve. You really see it doing things like the Offset Cones drill. You use The Dip to get the turn/lean started, but on small circles you see very clearly that the front tire is turned INTO the corner. The same thing is happening at higher speeds on bigger corners. The thing is that the circles/turns are so big we don't notice that the front wheel is pointed into the turn.

You can see what I mean at the 5:00 mark.

 

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Discussion Starter · #10 ·
Thanks for the suggestion. Here is the part I'm talking about:

Once lean is achieved


As the desired angle is approached, the front wheel must usually be steered into the turn to maintain that angle or the bike will continue to lean with gravity, increasing in rate, until the side contacts the ground. This process often requires little or no physical effort, because the geometry of the steering system of most bikes is designed in such a way that the front wheel has a strong tendency to steer in the direction of a lean.


The actual torque the rider must apply to the handlebars to maintain a steady-state turn is a complex function of bike geometry, mass distribution, rider position, tire properties, turn radius, and forward speed. At low speeds, the steering torque necessary from the rider is usually negative, that is opposite the direction of the turn, even when the steering angle is in the direction of the turn. At higher speeds, the direction of the necessary input torque often becomes positive, that is in the same direction as the turn.

This section doesn't tell me how fast it can happen, but at least it shows some random, anonymous Wikipedia poster agrees with what I'm feeling when I ride and try to counter steer. :doorag:
 

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I think it is a similar principal to the turn of an airplane. You initiate the turn, then stop applying pressure to the stick and the turn will continue, if you continue to apply pressure, you will eventually stall or roll the plane.
 

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wrong

I think it is a similar principal to the turn of an airplane. You initiate the turn, then stop applying pressure to the stick and the turn will continue, if you continue to apply pressure, you will eventually stall or roll the plane.
This is going just one assumption too far. If you take pressure entirely off of the bars, the gyroscopes will stand up and go straight (not continue to turn). That's why you continue to apply pressure until you're through the turn.
Definitions and descriptions can be argued too. Let's say you are in a left-hand sweeper and you haven't got enough lean to make it through the turn. You're already leaning left and pushing on the left handle bar. You have 2 choices, to make the correction needed to make the curve; cut speed or increase counter-steer. At speed on a 2 wheel conveyance, you steer by the amount of lean you apply, not by how much you turn the bars. In a lean you are balancing two forces to keep the lean angle at the desired amount that will allow you to travel in the direction that you need to go. Centrifugal force wants to stand up the bike and lessen your turn, while gravity wants to pull you down towards the pavement. Lean angle and speed are the controls that we use to balance them.

Richard
 

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The is a big difference in increasing pressure and maintaining pressure, if you increase pressure while counter steering the bike will continue to lean until you hit the ground. Maintaining pressure is applying only enough pressure to keep the bike in the lean as needed. Once you have reached the apex of the curve you can then apply opposite pressure to bring the bike to an upright position.
 

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Applying enough pressure to move the bar 1" in counter steer? That is quite a bit. If going slow enough you could put yourself not the ground.

If going fast enough it might just be a tight turn.



It all depend on speed.
 

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Besides depending on the speed it also it dependent on the length of the handlebar used to initiate the turn. I realize this is a Goldwing forum but we also ride many different styles of bikes and different styles were depicted in some responses. But 1 inch on a sport bike would initiate an entirely different turn than 1 inch on a cruiser with wide bars. Unless of course you're referring to 1 inch of movement at a specific number of inches from the steering head pivot.

John
 

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Here is a real question following the TS logic is if you pull on the opposite handlebar will the bike left off the road?
 
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