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Old 06-26-2013, 10:55 AM   #736
lnewqban
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Quote:
Originally Posted by Fajita Dave View Post
This will probably sound like a snide remark but answer me this. If the underlined statement is what you're experiencing then at what point does turning the handlebars do absolutely nothing?

From your experience at some point there needs to be a transition from direct steering to counter-steering. This means if you were to ride right in that transition point, steering will do absolutely nothing.
Good question, Dave.
At full left lock the bike turns to the left regardless the speed.

If the speed is low enough, my bike rolls or tends to fall to the left, while it still turns to the left.
There is a unique speed at which it will balance in a lean angle.

If the speed increases, my bike rolls or tend to fall to the right, while it still turns to the left.
If I do nothing to support it with my right foot, it will fall on the right side while describing a left turn.

There is a unique speed (call it transition speed if you will) at which the bike stays vertical while turning left.
Left steering will do something: to make the bike describe a left hand circle.
This is very difficult to achieve, due to body's movements and precise throttle, but not impossible.
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Old 06-27-2013, 04:36 PM   #737
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Quote:
Originally Posted by lnewqban View Post
Good question, Dave.
At full left lock the bike turns to the left regardless the speed.

If the speed is low enough, my bike rolls or tends to fall to the left, while it still turns to the left.
There is a unique speed at which it will balance in a lean angle.

If the speed increases, my bike rolls or tend to fall to the right, while it still turns to the left.
If I do nothing to support it with my right foot, it will fall on the right side while describing a left turn.

There is a unique speed (call it transition speed if you will) at which the bike stays vertical while turning left.
Left steering will do something: to make the bike describe a left hand circle.
This is very difficult to achieve, due to body's movements and precise throttle, but not impossible.
The motorcycle will always turn in the direction the front wheel is pointing (unless its off the ground or sliding). This is steering and for the most part how motorcycles turn just like cars do. You might be getting one thing confused here. When you are riding a motorcycle and turning left, the front wheel is point left no matter what speed you are traveling. Counter-steering only changes your lean angle which allows you to turn sharper, go straight or anything in between.

I'm going to throw a variable into the experiment you mentioned. Your experiment was to turn the handlebars left till the lock and then ride very slowly (lets say around 1mph or less). For you the motorcycle still fell left and I assume it fell pretty slowly at first and gained speed the further it fell right?

Now throw this variable in there and tell me your results. Ride with the handlebars locked left just like before at 1mph or less (same as your experiment). Only this time the moment the motorcycle begins to fall left, immediately turn your handlebars to the right. Tell me the results of what you feel. Make sure your left foot is ready to catch you.
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Old 07-01-2013, 10:26 AM   #738
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Quote:
Originally Posted by Fajita Dave View Post
........You might be getting one thing confused here. When you are riding a motorcycle and turning left, the front wheel is point left no matter what speed you are traveling. Counter-steering only changes your lean angle which allows you to turn sharper, go straight or anything in between.
Maybe I didn't understand your previous question, Dave; so, we agree on that: left steering = left turning, ..........as long as the two patches are planted on the road (sand doesn't care what your steering is).

The rolling is our point of discussion then.

This is how I see it:
1) Bike that turns generates a centrifugal force.
2) Bike that doesn't lean to compensate that centrifugal force with its weight, falls away from the center of the turn.
3) Bike that turns in steady way must be at a lean angle that perfectly balance centrifugal force and weight force.
4) Making a bike going on a straight line roll is best achieved by making the bike turn.


My trivial point for explaining the above question about the velocity at which steering becomes counter-steering is based on the magnitude of the centrifugal force.
For zero mph, that force doesn't exist; only the weight does.
For zero mph, that weight force moves off-center as I turn the steering bar (at least for my motorcycle), inducing a rolling moment toward the side the steering bar was turned.
For very low speeds, the roll moment induced by that centrifugal force (note that it depends on the square of speed) is weaker than the roll moment induced by the off-center weight (at least for my motorcycle).



According to above posts, including yours, what I have explained doesn't happen for other types of motorcycles.
For those bikes, due to steering geometry and wider tire profile, the weight moves off-center toward the same direction in which centrifugal force points and in opposite direction to the steering input.
For such bikes, there is no transition speed, as soon as, and even before, the bike starts moving, counter-steering is happening.
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Old 07-03-2013, 10:39 AM   #739
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Here's a visual representation for any noobs that still don't get it:

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Old 07-06-2013, 06:24 AM   #740
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Question

Somebody mentioned earlier in the thread that the front wheel/tire is always pointing in the direction that the bike is turning unless it is sliding or off the ground. In order to add some confusion to the thread I want to talk about the in-turn counter-steering. We have established that you have to countersteer to initiate a lean. Once you are leaning you have to countersteer to prevent the bike from falling on it's side (especially at low speeds. This is what I posit confuses people about the mythical steering/counter-steering transition speed. At very low speeds, once the bike is turning you have to steer very hard into the turn to prevent the bike from falling. The initial counter-steer compared to the in-turn counter-steer is nearly imperceptible.)

Some people describe their bikes as very eager to turn or very eager to stand up and go straight while turning. They describe their bikes as having to be "Held down" in a turn. If their bike is actually trying to stand up and has to be continuously counter-steered into the turn I wonder if the front wheel is actually pointing into or away from the turn. Due to the flexible nature of a tire it is possible that the tire is not slipping so much as the contact patch is flexing and rotating in relation to the rest of the tire.
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Old 07-06-2013, 12:41 PM   #741
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And for those who still don't believe, look at 1:50

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Old 07-06-2013, 03:11 PM   #742
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Whatever else, that was impressive.
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Old 07-06-2013, 03:29 PM   #743
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Quote:
Originally Posted by henshao View Post
Somebody mentioned earlier in the thread that the front wheel/tire is always pointing in the direction that the bike is turning unless it is sliding or off the ground. In order to add some confusion to the thread I want to talk about the in-turn counter-steering. We have established that you have to countersteer to initiate a lean. Once you are leaning you have to countersteer to prevent the bike from falling on it's side (especially at low speeds. This is what I posit confuses people about the mythical steering/counter-steering transition speed. At very low speeds, once the bike is turning you have to steer very hard into the turn to prevent the bike from falling. The initial counter-steer compared to the in-turn counter-steer is nearly imperceptible.)

Some people describe their bikes as very eager to turn or very eager to stand up and go straight while turning. They describe their bikes as having to be "Held down" in a turn. If their bike is actually trying to stand up and has to be continuously counter-steered into the turn I wonder if the front wheel is actually pointing into or away from the turn. Due to the flexible nature of a tire it is possible that the tire is not slipping so much as the contact patch is flexing and rotating in relation to the rest of the tire.
Bikes that have to be held down with constant pressure on the bar is due to the geometry (mostly bikes that have a lot of trail built in for stability). How the suspension compresses in a turn and tire profile have a heavy effect on this too. When the front tire on my sportbike gets worn I have to hold it down into the turn. Its perfectly neutral with a new tire to the point I don't even need my hands on the handlebars.

lnewqban I know what you're saying but it still doesn't seem to work that way in practice for me. As you said maybe its because of the narrow tire on your 250. The contact patch wont roll as far off center compared to a wider tire when the handlebars are turned to full lock. Just for the sake of it I've been practicing more trials type riding on my mountain bike and dirtbike with the same results I explained above. Tried it with the sportbike too . There wasn't much to "balance" with when the speedometer was reading 1mph but it still seemed to favor counter-steering to create lean angle the way I wanted. Body position and movement has way to much of a deciding factor at next to no speed.
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Old 07-06-2013, 07:40 PM   #744
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Holy shit!


Do any of you fuckers actually ride?
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Old 07-06-2013, 08:39 PM   #745
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Quote:
Originally Posted by FlySniper View Post
Holy shit!


Do any of you fuckers actually ride?
Everyday You've over doubled my post count in roughly the same time frame.... just sayin'.
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Old 07-06-2013, 09:39 PM   #746
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Quote:
Originally Posted by Fajita Dave View Post
............lnewqban I know what you're saying but it still doesn't seem to work that way in practice for me............. Just for the sake of it I've been practicing more trials type riding on my mountain bike and dirtbike with the same results I explained above. Tried it with the sportbike too . ..................... Body position and movement has way to much of a deciding factor at next to no speed.
Thanks for honestly trying all that, Dave.
Then, we could conclude that for most bikes, in a practical way, counter-steering works for any speed above zero.
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Old 07-06-2013, 09:48 PM   #747
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Quote:
Originally Posted by henshao View Post
Somebody mentioned earlier in the thread that the front wheel/tire is always pointing in the direction that the bike is turning unless it is sliding or off the ground........................Some people describe their bikes as very eager to turn or very eager to stand up and go straight while turning. They describe their bikes as having to be "Held down" in a turn. If their bike is actually trying to stand up and has to be continuously counter-steered into the turn I wonder if the front wheel is actually pointing into or away from the turn. Due to the flexible nature of a tire it is possible that the tire is not slipping so much as the contact patch is flexing and rotating in relation to the rest of the tire.
According to how the geometry of the steering and tires (width and patch deformation) work for each case during a turn, once the balance lean angle is reached, there are over-steering, neutral and under-steering motorcycles.

http://books.google.....page&q&f=false

Read page 315~317.


lnewqban screwed with this post 07-06-2013 at 10:40 PM
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Old 07-06-2013, 09:52 PM   #748
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Quote:
Originally Posted by Fajita Dave View Post
Everyday You've over doubled my post count in roughly the same time frame.... just sayin'.

Duh. You missed my point.

Try again.


You are so caught up in this .... debate.... that you can use no other lense to see the world through? That makes this even funnier.

A while back I posted something to the effect that it takes less than a second to figure out contersteering.... but you need to be on two wheels to figure it out.... If you can't figure it out, then it stands to reason you don't ride. (Not you in particular, but "you" as in the general population.)

Oh, oh, oh! WAIT! Let's do the "miles this year" dick wagging thing at each other next! (I can't find the gay smiley, but you get the idea.)
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Old 07-06-2013, 10:35 PM   #749
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Quote:
Originally Posted by henshao View Post
Somebody mentioned earlier in the thread that the front wheel/tire is always pointing in the direction that the bike is turning unless it is sliding or off the ground. In order to add some confusion to the thread I want to talk about the in-turn counter-steering. We have established that you have to countersteer to initiate a lean. Once you are leaning you have to countersteer to prevent the bike from falling on it's side (especially at low speeds. This is what I posit confuses people about the mythical steering/counter-steering transition speed. At very low speeds, once the bike is turning you have to steer very hard into the turn to prevent the bike from falling. The initial counter-steer compared to the in-turn counter-steer is nearly imperceptible.)..........
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Old 07-07-2013, 08:09 AM   #750
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Good to see out tracking get a metion at last.
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