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Blake
Posted on Monday, October 11, 2004 - 10:04 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

You come out of a lean in opposite fashion to how you initiate a lean. Turn the bars further into the turn.

How negotiating a turn works on a bike...

1. Initiate lean usually by counter-steering, ie steering away from the curve (turning front wheel towards outside of curve.)

2. Cease further leaning and initiate turning by steering into the inside of the curve.

3. Hold a constant steering input through the turn maintaining lean. Some bikes will remain on track with no steering input, some will require constant steering pressure/input. This depends on tires, suspension settings, and steering geometry. Make minor adjustments through throttle and steering modulation where more throttle/speed increases turning radius and less decreases turning radius.

4. Initiate turn exit and uprighting of bike by turning the front wheel further into the turn.

Whether we realize it or not everyone riding a two wheeled single track vehicle follows the above general procedure whenever they make a turn, no matter the speed. Even at very slow speeds the bike/rider MUST lean into the turn before the turning can initiate, albeit that lean can be at very slight angle.

The only thing that differs between slow and high speed turning is the hindering effect that gyroscopic action imparts causing the rider to put significantly more force into turning the front wheel.
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Rocketman
Posted on Monday, October 11, 2004 - 10:06 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Then no doubt Bob, it will be our loss. Or will it? Come to think of it, you don't contribute that much anyway so why bother coming here to tell us?

Bet you can't push the inside bar on that Triumph either.

Rocket
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Buellnuts
Posted on Monday, October 11, 2004 - 10:44 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Ouch, that hurt.

Which Trumpet Rocket? There's three.

Be specific fat boy.

Bob

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Buellnuts
Posted on Monday, October 11, 2004 - 10:46 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Oop,s hope I don't get kicked out for slipping that one in there, But God it was just perfect timing LMAO

Bob
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Rocketman
Posted on Tuesday, October 12, 2004 - 04:55 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Very informative post their Bob. Thanks for your contribution to a topic that obviously interest you greatly, but why am I not surprised Blake hasn't deleted your insulting and much off topic post. Nope that isn't a question.

Now go run back into your hole you scrawny little Triumph riding c\runt with the big ego.

Rocket
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Rocketman
Posted on Tuesday, October 12, 2004 - 05:55 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

You come out of a lean in opposite fashion to how you initiate a lean. Turn the bars further into the turn.

No you don't. That's ridiculous. How can you turn more into a corner when you're already leaned over in it, to steer out of it? You'll continue to keep turning.

You turn out of a lean the opposite way to it and this is where people get lost in the world of counter steering. This is because YOU stop forcing the counter steer by releasing the pulling pressure on the outside bar, the effect of which allows the bike to lift towards upright. Catching the lift and steering into the lift without applying too much counter steer is how you get it back up.

1. Initiate lean usually by counter-steering, ie steering away from the curve (turning front wheel towards outside of curve.)

Nope, wrong again. You turn into the corner. Counter steer only comes into it once the machine is past upright. If you steer away from the curve before, as you describe, you will go the other way. Counter steering does make the machine lean the opposite way to the steer but attempting to initiate lean by counter steering is not how you initiate lean. Only when you've initially turned can you involve counter steer to aid the turning and leaning.

2. Cease further leaning and initiate turning by steering into the inside of the curve.

That could work. You might start getting it around the corner now.

3. Hold a constant steering input through the turn maintaining lean. Some bikes will remain on track with no steering input, some will require constant steering pressure/input. This depends on tires, suspension settings, and steering geometry. Make minor adjustments through throttle and steering modulation where more throttle/speed increases turning radius and less decreases turning radius.

Yep, I could agree with most of that but you're arse about face with your speed \ radius analogy. More throttle \ speed will decrease your turning radius if you're in the turn. Likewise, less will make you run wide, ie increase your radius.

4. Initiate turn exit and uprighting of bike by turning the front wheel further into the turn.

Nope, that's what you're doing in your 2nd observation, which you seem to understand there will steer you into the corner. You need to turn out of the corner, that balance between you counter steering and turning being separated as I described above.



I'm surprised by many of the comments in this thread. It seems some people don't actually know the science involved when they're steering a bike. I can't help but feel if you actually tried to get your brain around it you might benefit from it more so one day. It gives you the ability to initiate the motorcycle's behaviour from a more lateral stand point. If you know your motorcycle is capable of doing something more than you can fathom, I'd be asking myself what it is. More so if I liked riding hard and fast.

Rocket
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Bomber
Posted on Tuesday, October 12, 2004 - 08:54 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Rocket -- your last paragraph described me to a tee, and many others as well, I imagine

just because some use different words to describe the same thing you are attampting to describe doesn't mean they are uninterested, unskilled or beneath your notice, all it means is that the English (and/or American) language is a very imperfect tool to describe the topic on this thread -- if we were all using math, I have a feeling we'd be saying the same things in the same way, and would all be nodding sagly to one another . . . ..

alas, if that were the case, it would be over my head, if no one else's
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Reepicheep
Posted on Tuesday, October 12, 2004 - 10:51 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Bomber... Math can be just as imperfect as english, so you ain't missing a thing there. The arguments just get more formal and less accessible.

Can everyone else try and renew their efforts to make their points without the personal attacks?
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M1combat
Posted on Tuesday, October 12, 2004 - 01:51 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I'll try...

You can only affect the initial lean of the motorcycle two ways...

1. You can lean way off the bike and let your weight pull it over.
2. You can turn the bars and jerk the tirepatch out from under the bike.

You can modify lean angle with the throttle as well, more on that later.

Number one is futile. You will indeed lean, but not very far and not precisely at all. The No BS Trainer bike of Keith Code's proves it.

Because objects in straight line motion tend to stay in straight line motion... When you turn the bars of a motorcycle the motorcycle will fall to the outside of the turn. Think of what would happen if you are heading down the road straight, you sit back and remove your hands from the bars, place one foot on the left bar (You'll need to be somewhat of a contortionist for this) and push it to the stop. You will end up on the ground to the LEFT of the bike on initial contact (beyond that is anyones guess and beyond the scope of the conversation). So... What happened? The bike pulled itself out from under you to the right (because you turned the bars to the right). But the lean was to the left. This is an extreme example of how you initiate a turn.

Lets go through the whole corner -

As you are aproaching the corner you pick your line. When it comes time to turn in, you steer the bars to the OUTSIDE (almost imperceptibly) of the turn. At this point the bike will begin to lean to the inside of the turn. This is countersteer. The bike will drop into the corner and begin to rotate in the direction of the turn. When you get to the desired lean angle you release SOME OF the pressure to the inside bar (or pull pressure to the outside bar if you must : )). Throughout the corner you continue to apply constant pressure to whichever bar you want. If it's the inside, you push, if the outside, you less. The steering head will come back to the point that it is pointing INTO the corner, but you will need to maintain countersteering pressure so the bike doesn't right itself as they are prone to do. This is still countersteering. In a perfect world you would maintain the same lean angle (and countersteering pressure) all the way through mid corner. As you are coming to the exit, you would begin to relieve pressure from the bars (allowing them to turn into the corner like they want to) and the bike will start to stand up. You can add throttle just before the apex and the added speed will also begin to stand the bike up (more centrifugal force will do this).

In the real world you might need to make an adjustment. To do this mid-corner you will ADD countersteering pressure at the bars (if you need to tighten the corner) or relieve some pressure (if you need to run a little wider). In the case of adding pressure, this will make the bike lean more and turn sharper. In the case of relieving pressure, this will make the bike stand up a little and go wider. This can be done with throttle input as well. If you add throttle, there will be more centrifugal force generated and the bike will begin to stand up a little and wont turn as sharp. If you remove throttle, the bike will lay over farther and will turn sharper.

Throughout the entire corner, you will be applying countersteering pressure to the bars to maintain lean angle. The ammount of pressure you apply will be determined by the lean angle you need to maintain.

Keith Code's no BS bike tells us that using your body to INITIATE lean changes is mostly ineffective and very imprecise. Therefore, you can only affect lean angle properly and precisely by handlebar input.

Lets try extreme actions mid-corner...

You are leaned into a corner... A left hand corner. You are maintaining countersteering pressure on the bars. At mid-corner you decide you have had enough of life. You have two choices... You can apply more countersteering pressure or remove pressure (or I guess rev the pee out of the bike and dump the clutch...). If you apply more pressure, the bike will lean farther until the point that it low-sides. Because the bike is leaning farther and farther, the corner will continue to tighten (given the same speed). If you decide to release all countersteering pressure, the bars will turn INTO the corner because of the caster and camber of the front tire (because you are on the inside of the tirepatch). The bike will right itself and go straight if you "just" relieve pressure (it may do a few tank slaps before it begins to control the oscilation, but this is due as much to the bike's geometry as it is to rider weight flailing around on top of the bike). If you actively steer the bike INTO the corner (beyond the steering angle the bike wants), the bike will stand up and high-side you immediately.

What does this tell us? This tells us that applying countersteering pressure initiates lean. Maintaining countersteering pressure keeps the bike leaned over. and removing countersteering pressure allows the bike to stand up. Please keep in mind that counter steer is wholy independent of the actual steering head angle. The only time the steering head itself is actually pointed to the outside of the turn is when you are snapping the bike into the lean angle you want. After that, when you have relieved counter steering pressure (but NOT all of it) the steering head in pointed to the inside a little, but you are still maintaining countersteering pressure. The steering head WANTS to turn to the inside in order to right the bike. You are applying pressure to keep it from doing so.

Here is why the steering head wants to turn to the inside...

The normal contact patch at no lean angle looks like this \_/... When you lean, it looks like
\
this _/. When leaned, there is a certain magnitude of force exerted by the pavement into the tire. The force is exerted at the inside portion of the tire. This force tries to pull the inside of the tire backwards. This is ONE OF the forces that makes the steering head want to turn into the corner and stand the bike up. The other is the interaction between caster, camber and trail.

Take a set of forks, triple clamps, a wheel and tire and try this. Hold the setup upright with NO rake (the forks straight up). Now lean them to the side like they would if they were attached to a leaning motorcycle (don't turn them like there is input at the bars, just lean them over). They will just lean over...

Now, add 45 degrees of rake and do the same thing. As soon as you move them beyond their balance point (straight) the tire will want to fall over (or turn into the corner).
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Blake
Posted on Tuesday, October 12, 2004 - 02:56 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Rocket,
I'm not 100% sure about many things, but of how steering/turning on a motorcycle works, I am absolutely 100% certain. I didn't fail-out of Advanced Dynamics or Physics either.

Here's a simple trial anyone can do to help wrap their mind around how a motorcycle responds to steering input and turning...

Find a center striped straight closed course track that is completely devoid of traffic.

Ride your bike going down the track in 2nd or 3rd gear at around 35 mph and tracking dead-on the center stripe.

Practice turning the bars/front wheel one way and then the opposite way to return back onto the centerline to resume a straight upright track.

Once you are comfortable with the above maneuver, start to take careful precise note of your front tire's track as you perform the maneuver.

What happens to the front tire track as you initiate turning the front wheel? Which way does the bike lean?

Once you understand what the front tire track is doing during the maneuver, cease observing that and focus on what your handlebar/front end steering is doing. Observe the relation of the front wheel heading relative to the axis of the bike. DON'T CAUSE YOURSELF TO CRASH OR RUN OFF THE TRACK!

You can also easily see what is happening if you maintain a slalom type weave back and forth across the center of the track while carefully noting front wheel turning attitude relative to the axis of the bike.
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Blake
Posted on Tuesday, October 12, 2004 - 03:07 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

M1 (Donald),
Good write-up. Just one clarification...

Not all bikes, my '97 Cyclone included, require constant pressure on the bars to maintain a turn once leaned over. In fact most modern sport bikes are neutral steering through turns. The XB's are not, which is why some moto journalists derided them for their unconventional handling. Note that I've raised the forks on my Cyclone by approximately 1/4" (6mm) to achieve neutral steering through the turns. Before that I had to maintain some counter-steering input to maintain the lean and turn, though as you say, once in the turn and leaned over the front wheel absolutely positively points towards the inside of the turn.
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Blake
Posted on Tuesday, October 12, 2004 - 03:29 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Maybe this old graph will help...


Steering Angle Versus Time in Turning a Motorcycle at Speed


The best illustration would be via video cam showing a view of the front end and the road/lean angle. Wish I had one.
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Blake
Posted on Tuesday, October 12, 2004 - 03:37 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

An old thorough discussion on the subject...

http://www.badweatherbikers.com/buell/messages/4062/10250.html
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Fullpower
Posted on Tuesday, October 12, 2004 - 07:48 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

next ride on an empty road, do something interesting/illuminating: ride for a bit with your left hand only on the throttle grip. it is a bit uncomfortable, but illustrative of stearing dynamics. good luck, be careful, dean
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Jlnance
Posted on Tuesday, October 12, 2004 - 08:51 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Blake - A graph . I really don't know that much about motorcycles, but I feel right at home with graphs and math.

It does illustrate something I have been confused about. I have heard implications that turns/lean are initiated by counter-steering, but after you get into them they are steered 'normally'. Your graph clearly demonstrates this.

When I turn the bike, I press on the bar in the direction I want to turn. I never conciously pull it back in the other direction. Perhaps it happens unconciously. But one thing I have noticed that seems at odds with this is that if I am in a long turn (exit ramp is great example) and I need to tighten the turn, I counter-steer more. The implication from the graph and the discussions is that after you initiate the turn you are steering 'normally.' Comments?
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M1combat
Posted on Tuesday, October 12, 2004 - 10:38 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

No, you are not steering normally... ANY time you want to initiate lean or add lean angle, you steer to the outside of where the bike wants the steering head to be to add the lean angle. To remove lean angle, you allow the steering head to steer into the corner (it will do this on it's own). Granted, you can also add lean angle by reducing throttle or remove lean angle by adding throttle.

I think that this illustration would indicate the pressure exerted on the bars through a turn -



The initial spike is the initiation of lean angle where you are pressing on the bar to get the bike to snap into the desired lean angle. On a leasurely jaunt this spike would be much less pronounced. The flat area would carry you about to the apex and the rest would be as you are allowing the steering head to do as it will (which is stand the bike up) until the final correction to get to a nice straight line. Notice that for the duration until the very end (and that part isn't really necessary) you are applying countersteering force.

Even when trying to stand the bike up a little for something like a double apex corner, you wouldn't actually turn with the direction the steering head wants to go, you would just resist it's tendency to turn to the inside a little less. The proper way to double apex fast on a track is with more throttle though, but this conversation seems to be centered more around countersteering input and what IT does...
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Rocketman
Posted on Tuesday, October 12, 2004 - 11:37 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

M1 there are so many things wrong with your comments you clearly don't understand what you are talking about, and no doubt you are confusing others, as you are me.

Nothing you have tried to explain allows me to understand how counter steer initiates lean and I defy both you and Blake to approach a corner at speed and turn the bars the opposite way in order to start the leaning process. You simply must at first turn into the corner to direct the machine the way you wish it to go. Once turning the bike will start to lean over and then, and only then, will counter steer become something the operator of the machine can do something with.

On the more ridiculous you clearly don't understand the relationship of the machines steering head with anything rear of it, including throttle response, and the effect the steering head has on counter steer. In all your analogies where you make reference to the steering head you appear to have the steering head doing or going the opposite way to which it actually is \ does.

I did get a good chuckle out of your mono cycling antics though but again you got it arse about face. If you held your contraptions front end at 45 deg of rake then leaned it over to one side your strange mono cycle type front end would steer opposite to the lean because you are essentially turning the headstock (if it were present of course ) the opposite way to the lean. This is because the headstock resides behind the axle as does the tyres contact patch. Now add the rest of the motorcycle to your front end then understand that the headstock is the pivotal point for the steering to act around, thus sharing a direct relationship with every movement the motorcycle makes in any direction. What we are seeing here is the machines counter steer effect - not to be confused with the operators input .

I strongly suggest you go out and play rather than listen to Blake blow smoke up your arse. You and he are both plain wrong, he being the all round clever bastrd or not.


Blake, where is that graph from? It's bullshit.

Rocket
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Steveb
Posted on Tuesday, October 12, 2004 - 11:52 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Blake,

Nice job of refining the description of countersteering.

Rocket,
If you're serious about countersteering, take a bicycle at 10 to 20 mph on the straight and level, and take your hands off the bars. Then take one index finger and gently push forward on one bar end. That's all!
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Rocketman
Posted on Wednesday, October 13, 2004 - 12:12 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I understand totally what's going on thank you very much, but some people are a little confused about initiating a turn using counter steer as the primary force, the direction the headstock faces when acting in a corner and the relationship between lean angle \ forward motion \ centrifugal force and the power applied.

It's simple really, go ride your bloody motorbike then report back, like I did.

Rocket
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Blake
Posted on Wednesday, October 13, 2004 - 01:15 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Sean,
Try again. This time facing forwards on the bike.
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M1combat
Posted on Wednesday, October 13, 2004 - 01:18 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I have... Many times... Of the 9200 miles on my 12R I have spent roughly 5000-6000 on my favorite 35 mile stretch of mountain road (which is about .5 miles from my house).

I think (based on your second to last post) that we are just talking different terms... You ride a motorcycle so you obviously are doing the proper things. I think this is where I am losing you...

When I say countersteer, I'm not talking about the angle of the front tire, steering head or handlebars relative to the rear of the bike. I'm talking about the direction from it's neutral point (which will be a number of degrees towards the inside of the corner) while leaned over that you would attempt to hold it at. If the direction of the front end is left in a left hand corner, that's fine (and it is)... But countersteer is the act of not letting the front end turn into the corner as much as it wants to. This is mid-corner. If you DO allow the steering head to do what it wants, the bike will stand up. This is what bikes do. They oscillate back and forth until they stand up and ride straight (mostly : )) down the road by themselves (unless the speed is too low).

Upon initial turn in I MOST CERTAINLY DO TURN THE BARS TO THE OUTSIDE OF THE TURN. As the bike begins to lean in, the bars automagicaly (or by following the laws of physics, your choice) turn to the inside as well. This is not countersteer. This is the laws of physics. The moment I start to put pressure on the bar to limit the amount I allow the bars to turn in, I am countersteering.
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M1combat
Posted on Wednesday, October 13, 2004 - 01:24 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

"This is because the headstock resides behind the axle as does the tyres contact patch."

Ummm, no. The contact patch lies directly under the axle. The contact patch DOES indeed lie behind the point at which the ground and the steering head angle meet... 83mm on my Buell with stock tires, probably about 81.5mm with the Metzeler M1's.
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Opto
Posted on Wednesday, October 13, 2004 - 03:16 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Rocket, I think they are trying to say that if you want the bike to go around a right-hand corner, the handlebars initially have to be turned slightly to the left to start the turn.
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Rocketman
Posted on Wednesday, October 13, 2004 - 05:48 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

When I say countersteer, I'm not talking about the angle of the front tire, steering head or handlebars relative to the rear of the bike. I'm talking about the direction from it's neutral point (which will be a number of degrees towards the inside of the corner) while leaned over that you would attempt to hold it at. If the direction of the front end is left in a left hand corner, that's fine (and it is)... But countersteer is the act of not letting the front end turn into the corner as much as it wants to. This is mid-corner. If you DO allow the steering head to do what it wants, the bike will stand up. This is what bikes do. They oscillate back and forth until they stand up and ride straight (mostly ) down the road by themselves (unless the speed is too low).

M1, spoken with clarity. Now I understand what you are saying and yep I can see how you get that comment to work, though I would question your analogy of why you would input counter steer for the reason you suggest. That said, we can go back to square one if you believe this....

Upon initial turn in I MOST CERTAINLY DO TURN THE BARS TO THE OUTSIDE OF THE TURN.

NO YOU DON'T.

As the bike begins to lean in, the bars automagicaly (or by following the laws of physics, your choice) turn to the inside as well. This is not countersteer. This is the laws of physics.

YOU PUT THEM THERE. YOU STEERED THEM IN.

Stand at the side of your bike and take it for a walk down the street. You DON'T counter steer to make it turn, you point it in the direction it wants to go and you lean it over. This doesn't change when you are riding it at low or high speed. If you bring counter steering to the party you can only do so once you've initiated the turn unless the bike was leaning the opposite way to start with.

Ok, your next post is incorrect too. You weren't observing correctly.

Ummm, no. The contact patch lies directly under the axle. The contact patch DOES indeed lie behind the point at which the ground and the steering head angle meet... 83mm on my Buell with stock tires, probably about 81.5mm with the Metzeler M1's.

You leaned the forks back 45 deg so you need to draw a line all the way down their center until it hits the floor. Where that line hits the floor is where we're concerned.

Let's digress a little. If your forks were upright at 90 deg to the horizon, spindle placed in the center at the bottom, when you turn those forks the spindle will remain flat, ie parallel to the ground. If you lean the forks back 45 deg, when you turn them the spindle will lift and fall at opposite ends. The lift end will be inside the turn which in your mono cycle analogy would make it turn outwards to the corner. Don't confuse this with anything else.

The line you have drawn down the fork leg to the ground and the spindles rise and fall action is why the contact patch is considered to be behind the spindle. Now draw a line directly down from the spindle to the ground. If you look at the triangle you've just drawn with the line of the forks to the ground and the drop from the spindle to the ground that triangle is your TRAIL. Your CASTOR ANGLE is the opposite to this, ie the triangle in front of the headstock to the vertical line drawn up above the spindle position.



Rocket, I think they are trying to say that if you want the bike to go around a right-hand corner, the handlebars initially have to be turned slightly to the left to start the turn.

That's what they should be afraid of Opto!

Rocket
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M1combat
Posted on Wednesday, October 13, 2004 - 11:30 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

"If your forks were upright at 90 deg to the horizon, spindle placed in the center at the bottom, when you turn those forks the spindle will remain flat, ie parallel to the ground."

I specifically said DO NOT TURN the forks. I said LEAN them with no steering input.

"M1, spoken with clarity. Now I understand what you are saying and yep I can see how you get that comment to work"

Which is funny, because I've said that before...

"NO YOU DON'T. "

YES I DO. : )

"Stand at the side of your bike and take it for a walk down the street. You DON'T counter steer to make it turn, you point it in the direction it wants to go and you lean it over. This doesn't change when you are riding it at low or high speed. "

Yes, it does change. You have a LOT more momentum built up in the direction you are traveling AND you have THREE large gyro's that don't want to rotate.


Try this Sean...

Head on down the road at about 45-50MPH or whatever you choose as long as it's over about 25. While going down a perfectly straight section of road give a VERY gentle PUSH to the LEFT side bar. This push should be a push forwards... Not down, up or back. Do not move your arse on the seat. Just a gentle push to the bar. Please report what happens. Until then, I'm not interested in arguing with you. You can not convince me that I don't turn the bars to the outside of a turn to initiate lean. Yes, lean CAN be initiated by body movement but it's imprecise and slow. Take your pick if you must.
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Rocketman
Posted on Wednesday, October 13, 2004 - 09:59 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Ok, seeing as you're giving me a bollocking for not listening let's look at your set of forks because yet again you are wrong.

Take a set of forks, triple clamps, a wheel and tire and try this. Hold the setup upright with NO rake (the forks straight up). Now lean them to the side like they would if they were attached to a leaning motorcycle (don't turn them like there is input at the bars, just lean them over). They will just lean over...

No they won't they will turn. Do you know why? Well I'll tell you just in case you doubt me.

Lean (not turn - ok) those straight up forks over and hold 'em there for a second will ya. Now you got them held over I want you to draw a line along the floor starting at the tyre contact patch and at 90 deg to it and about a few feet long. Now you've drawn that line I want you to draw another one. This time start at the inside end of the spindle and carry the spindle line through to the ground. You should now have two lines, one on top of the other, and at some point along their length they should meet at ground level. Now draw another line from the very top of the tyre to the point where the spindle line and the horizontal line meet so you now have three lines on top of one another. I trust you're following this? Now we get the good part. If you rotate these lines together you've now got a cone. Wow imagine that M1, a cone! Now you know what happens if you roll a cone along the floor don't you? That's right, it turns, and so your leaning forks will. Now this begs a question doesn't it. If counter steering was applied to those forks would they turn in or out? Better to ask what the effects of turning into the cone would be so as you don't complicate yourself. I know what happens next. Do you?



As for you speaking with clarity, that is what you hadn't done before, no matter what you may or may not have said. That was my point, that's all. .

NO YOU DON'T

As for your gyro observation........

Head on down the road at about 45-50MPH or whatever you choose as long as it's over about 25. While going down a perfectly straight section of road give a VERY gentle PUSH to the LEFT side bar. This push should be a push forwards... Not down, up or back. Do not move your arse on the seat. Just a gentle push to the bar. Please report what happens. Until then, I'm not interested in arguing with you.

Awe man that's a shame because I already know the answer. It's going to do exactly what YOU expect it to do, but let me shout this out to you, THAT'S NOT WHAT WE'RE DISAGREEING ABOUT!!!!

You do not induce counter steering to initiate a turn, but yes if you push the fcuking bar the machine will turn - obviously. That doesn't prove a bloody thing. All you did there was counter steer, therefore you should be more concerned about the very next thing you're going to do because you're about to learn the hard way that that is not the way to initiate the turning of a motorcycle.

Suggest M1 you go turn into a corner and perhaps I won't argue with you until you have.

Rocket
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Outrider
Posted on Wednesday, October 13, 2004 - 10:04 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Geez...I swear not many of you actually go practice what you preach. If you did, there would be less of you on the BWB and I would be exceeding my budget for funeral flowers.

Damn, Read a good book and go practice. If that is beyond you, give up the sport.
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Aesquire
Posted on Thursday, October 14, 2004 - 12:23 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I had to go back & see where the lack of communication is. I think it's a terminology issue, not really a disagreement.

Rocket said "What we are seeing here is the machines counter steer effect - not to be confused with the operators input ."

From the Tuesday, October 12, 2004 - 11:37 pm: post.

So Rocket is talking about a factor in the stability of the machine, as it corners. He is seeing it as a mechanistic system of balance & feedback. He is NOT talking about "countersteering" as I am using it.

Blake, M1 & myself are referring to a rider's input. We are talking about steering the contact patch to make the bike fall over ( roll ) or stand up, or do corrections.

Or am I wrong here?
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M1combat
Posted on Thursday, October 14, 2004 - 01:30 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

You may be correct, but he has said many times that I don't turn the bars to the outside of the corner to initiate a turn.


Rocket - In my example of the monocycle I was attempting to get you to see what will happen with the steering head in that situation. I was pointing towards the tendency of a motorcycle to stand itself up and go straight with no rider input aside from a steady throttle. I didn't mention rolling the tire at all.

"I had to go back & see where the lack of communication is. I think it's a terminology issue, not really a disagreement.

Rocket said "What we are seeing here is the machines counter steer effect - not to be confused with the operators input .""

Correct - we discussed this already with the noun vs. verb thing. My assumption was that it is both, although I think that the bikes own tendency to stand itself up is called something other than countersteer. I'll look it up. A force applied in the opposite direction of the way the bike wants to steer IS called a countersteer by many professionals however. In any case though, we already decided that if one must, they could call both things countersteer. The one we are talking about is the rider input and what a rider does to control the bike. If Sean would like to discuss the geometry of a modern motorcycle and how it abides by the laws of physics... Fine. But that is, I believe, a topic for another thread.

Now, back to the turn initiation thing (maybe if we work all the way through the turn we could rival the venerable war thread?). I'll ask you this Rocket... In my request above, I asked you to give a gentle push to the left bar. You said "but yes if you push the fcuking bar the machine will turn - obviously. That doesn't prove a bloody thing.". Right. It doesn't. Because you didn't say which direction the bike will turn. Which direction will the bike turn? I'm not talking about the first 5mm of travel but if you were to continually apply that gentle force to the left bar until you come back around in a circle, which way would the bike turn? Clockwise or anti-clockwise? Left or Right?

Just FYI - Being the type to practice what I preach I tried my own little expirament multiple times on my way home from work. ALSO... On my drive I let go of the handlebars and just used my hips to initiate lean. Uhhh, yeah... That doesn't work too good. The bars do indeed immediately turn to the inside of the corner (the direction I thought I was trying to turn anyway, more on that in a moment), but it feels VERY imprecise. Here's the thing though... The bike would initially turn in the direction I moved my hips but would then turn back and right itself (of course). It STILL turned out to be a countersteering input because the overall resulting turn was ALWAYS the opposite of the initial direction that I turned the bars (with my hips). It worked the same way as actually turning the bars with my hands, but felt MUCH less controlled and precise.
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Blake
Posted on Thursday, October 14, 2004 - 05:23 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

On the track hurtling into a hard left-hander I crank the front wheel hard to the right, the bike leans hard to the left and I let the wheel/bars come back around and turn into the curve. That's it. Anyone who tries to peddle anything different is sorely mistaken.
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