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Old 01-08-2013, 09:46 AM   #151
Jim Moore
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Quote:
Originally Posted by dwoodward View Post
Both of you should go find a copy of "The Upper Half of the Motorcycle", which discusses this sort of thing.
I don't want to read it unless it agrees with me.
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Old 01-08-2013, 01:09 PM   #152
Lion BR
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Now, my question to you is this: at what direction is your front wheel pointing, in relationship to the motorcycle front-rear axis, when you are at a 60 mph curve to the right? Is it pointing to the right (into the curve), straight, or to the left (counter to the direction of the curve)?
To answer to my own question:

When at speed, when I enter a corner, from the time of the turn in, to the apex and to the exit, when on a smooth arc with no need for corrections, the *impression* that I get is that I'm counter-steering the whole way through. That is, my from wheel, at best, is moving straight, if not to the outside of the curve during lean. (Normal riding here, body straight or upper body slightly turned towards the inside of the curve, with normal tire pressures and NOT power steering - or steering with the rear tire).

The impression I have is that if I'm turning the front wheel to the curve (after initial counter steer), I'm riding too slow (u-turn example).

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Old 01-08-2013, 04:11 PM   #153
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Quote:
Originally Posted by Lion BR View Post
To answer to my own question:

When at speed, when I enter a corner, from the time of the turn in, to the apex and to the exit, when on a smooth arc with no need for corrections, the *impression* that I get is that I'm counter-steering the whole way through. That is, my from wheel, at best, is moving straight, if not to the outside of the curve during lean. (Normal riding here, body straight or upper body slightly turned towards the inside of the curve, with normal tire pressures and NOT power steering - or steering with the rear tire).

The impression I have is that if I'm turning the front wheel to the curve (after initial counter steer), I'm riding too slow (u-turn example).

Lion
It can be pointing straight ahead because the direction then wheel is pointing is not the only thing that causes a direction change where the rubber touches the ground. But this point is irrelevant because you are still pointing the tire further inward toward the curve than you would if you were countersteering. Countersteering is just the act of moving the tire out from under the mass of the bike and rider, that's it.

I think the car explanation posted was the best. If you turn left in a car your weight shifts to the right. If you slow down to 10mph your weight doesn't start shifting to the left. I hope that paints clearly how absurd a magical line where countersteering starts really is.
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Old 01-08-2013, 05:31 PM   #154
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Originally Posted by shaddix View Post
It can be pointing straight ahead because the direction then wheel is pointing is not the only thing that causes a direction change where the rubber touches the ground. But this point is irrelevant because you are still pointing the tire further inward toward the curve than you would if you were countersteering. Countersteering is just the act of moving the tire out from under the mass of the bike and rider, that's it.

I think the car explanation posted was the best. If you turn left in a car your weight shifts to the right. If you slow down to 10mph your weight doesn't start shifting to the left. I hope that paints clearly how absurd a magical line where countersteering starts really is.
I like the last part. Thank you

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Old 01-08-2013, 08:16 PM   #155
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Quote:
Originally Posted by Lion BR View Post
To answer to my own question:

When at speed, when I enter a corner, from the time of the turn in, to the apex and to the exit, when on a smooth arc with no need for corrections, the *impression* that I get is that I'm counter-steering the whole way through. That is, my from wheel, at best, is moving straight, if not to the outside of the curve during lean. (Normal riding here, body straight or upper body slightly turned towards the inside of the curve, with normal tire pressures and NOT power steering - or steering with the rear tire).

The impression I have is that if I'm turning the front wheel to the curve (after initial counter steer), I'm riding too slow (u-turn example).

Lion
The front tire is always following the direction of travel (there are some small variances but its complicated details that don't add up to much). If the motorcycle is actively turning left than the front wheel is pointing left in all riding situations with the front tire on the ground. A counter-steer is just briefly turning the handlebars further right to make the motorcycle lean left and vise versa. Once your lean angle is maintained (whether its up right or at maximum lean angle) than the counter-steer is over and the front wheel is following the exact line of travel.

Here's an example and we'll use a slow turn so you get lots of movement from the handlebars to make it work. Lets say your maintaining a left U-turn and the handlebars are halfway between straight, and full left to make the turn (so there's steering input available left to use). That handlebar position is basically the motorcycles current "center" to maintain that given lean angle and stability. If you turn the handlebars right of that "center" in the U-turn it will lean lower and tighten the turn. If you turn to the left of that "center" it will make the bike stand up and widen the turn. Mean while the front wheel is still always pointing left going through the left U-turn. That might be a little hard to follow after reading it but I suck at wording some things clearly.
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Old 01-09-2013, 05:09 AM   #156
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Lion BR and Fajita Dave are both correct. As Dave said, you are ALWAYS turning the front wheel in the direction of the turn - WHILE IN A TURN. You turn the wheel the opposite direction to INITIATE THE TURN via countersteering.

So in a turn, you may correct the radius of the turn/lean angle with additional countersteering inputs. So technically in a turn you are doing both... turning the wheel in the direction of the turn and countersteering to provide additional inputs as needed.

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Old 01-09-2013, 06:08 AM   #157
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Sorry to complicate things but I was under the impression that the fact the tire is leaned over provides enough camber thrust to cause lateral acceleration of the front end without having any steering angle at all. Of course this only applies to wide angle turns, and at higher speeds 40mph+ you can actually have the wheel turned in the other direction.
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Old 01-09-2013, 10:45 AM   #158
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Lion BR and Fajita Dave are both correct. As Dave said, you are ALWAYS turning the front wheel in the direction of the turn - WHILE IN A TURN.
Erm. So we're now completely discounting the "ice cream cone" effect that's been used for so long to explain why motorcycle tires are rounded instead of square?

(Which is neither here nor there, as far as countersteering is concerned...)
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Old 01-09-2013, 11:45 AM   #159
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Originally Posted by dwoodward View Post
Erm. So we're now completely discounting the "ice cream cone" effect that's been used for so long to explain why motorcycle tires are rounded instead of square?

(Which is neither here nor there, as far as countersteering is concerned...)
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Old 01-09-2013, 06:09 PM   #160
Lion BR
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Quote:
Originally Posted by shaddix View Post
Sorry to complicate things but I was under the impression that the fact the tire is leaned over provides enough camber thrust to cause lateral acceleration of the front end without having any steering angle at all. Of course this only applies to wide angle turns, and at higher speeds 40mph+ you can actually have the wheel turned in the other direction.
There you go. A magic number finally appears. And my impression that at 60mph on a curve, that my front wheel is NOT turned into the corner could be correct. It may not necessarily be the counter steering we speak of, but it is a counter steering.
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Old 01-09-2013, 07:12 PM   #161
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There you go. A magic number finally appears. And my impression that at 60mph on a curve, that my front wheel is NOT turned into the corner could be correct. It may not necessarily be the counter steering we speak of, but it is a counter steering.
Yes it could be correct, but I believe the right term is the wheel is outtracking, this has nothing to do with countersteering so please do not confuse the two.
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Old 01-09-2013, 07:32 PM   #162
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Originally Posted by shaddix View Post
Yes it could be correct, but I believe the right term is the wheel is outtracking, this has nothing to do with countersteering so please do not confuse the two.
The same way that a car's "counter steering" (as in drifting, for example) or a throttle steer for a motorcycle, where the front wheel(s) is(are) pointed outward to the curve, should not be called counter steering? Is it because the concept is too complicated and once you got it you don't want to lose it? Or is it because counter steer is a trademark for motorcycles and other two-wheel vehicles when referring to initiate a lean (turn)?
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Old 01-09-2013, 08:06 PM   #163
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Originally Posted by Lion BR View Post
The same way that a car's "counter steering" (as in drifting, for example) or a throttle steer for a motorcycle, where the front wheel(s) is(are) pointed outward to the curve,
The front wheel(s) is not pointed outward to the curve!!!! Its still following the exact line of travel!!! The frame itself is whats pointing toward the outside of the curve and rotates around the steering stem in this case.

The only possible way for the front tire to not be following the line of travel is if it were sliding or off the ground.

Camber thrust does have an effect on how far the handlebars are actually turned to make a given corner. However, its not a significant effect compared to the front wheel's direction deciding the radius of the turn. You could have a motorcycle with razor blades for tires (so no camber thrust what so ever) and it would corner just fine if not better than a rounded motorcycle tire. I'm pretty sure I remember reading something from a Moto GP mechanic about having razor sharp tires would be optimum for cornering. Of course they could never make a rubber tire handle that sort of load on a razor sharp point.
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Old 01-09-2013, 09:25 PM   #164
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Quote:
Originally Posted by Lion BR View Post
The same way that a car's "counter steering" (as in drifting, for example) or a throttle steer for a motorcycle, where the front wheel(s) is(are) pointed outward to the curve, should not be called counter steering? Is it because the concept is too complicated and once you got it you don't want to lose it? Or is it because counter steer is a trademark for motorcycles and other two-wheel vehicles when referring to initiate a lean (turn)?
Well words can have multiple meanings. So if you want to call two separate and disconnected concepts countersteering and confuse everyone you speak to, be my guest.
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Old 01-10-2013, 01:12 AM   #165
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Pro tip: Don't stare at your front tire while you're riding.

Speaking of knife edge wheels, I feel the need to ride a razor scooter now. A few weeks ago I rode one for a little bit, and its bugging me. I don't remember consciously countersteering to initiate a turn. I was just trying not to run into a pebble.
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