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Gyroscopic Effect

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Hi Racer,

It has been a while since last I graced the pages but I had to......comment here! Stop the madness!

 

" The gyroscopic effect of the wheel during cornering is manifested by a righting moment. To counteract the gyroscopic effect of the two wheels and thereby maintain equilibrium, the rider can lean into the turn in such a way that the resultant of the weight force and the centrifugal force generates a moment equal and opposite to the gyroscopic moment of the two wheels. The rider can achieve equilibrium without displacing his trunk in order to produce a displacement of the mass center towards the inside curve but the lean angle will be greater than the ideal roll angle calculated on the assumption that the gyroscopic effect is zero.

In this case, the righting moment generated by the centrifugal force an the moment generated by the gyroscopic effect are both offset (thank you Will!) by the overturning moment of the weight force.."

Vittore Cossalter

 

Who is Vittore Cossalter? And where did you find that hilarious quote?

 

 

Now can we discuss something that will help me get around the track faster?

 

Not in this thread. Not unless you completed high school physics anyway... ;)

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Hi Racer,

It has been a while since last I graced the pages but I had to......comment here! Stop the madness!

 

" The gyroscopic effect of the wheel during cornering is manifested by a righting moment. To counteract the gyroscopic effect of the two wheels and thereby maintain equilibrium, the rider can lean into the turn in such a way that the resultant of the weight force and the centrifugal force generates a moment equal and opposite to the gyroscopic moment of the two wheels. The rider can achieve equilibrium without displacing his trunk in order to produce a displacement of the mass center towards the inside curve but the lean angle will be greater than the ideal roll angle calculated on the assumption that the gyroscopic effect is zero.

In this case, the righting moment generated by the centrifugal force an the moment generated by the gyroscopic effect are both offset (thank you Will!) by the overturning moment of the weight force.."

Vittore Cossalter

 

Who is Vittore Cossalter? And where did you find that hilarious quote?

 

 

Now can we discuss something that will help me get around the track faster?

 

Not in this thread. Not unless you completed high school physics anyway...

 

You haven't Googled him yet? He is the world's leading authority on Motorcycle Dynamics....THe problem witht he quote is......I left a lot of stuff out like all the diagrams....It was late and I was sleepy!

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Oh.

 

I just found the quote funny because in plain English it basically says, "any gyroscopic effect is offset or balanced by other forces at a stable lean angle."

 

Well, duh.

 

Hence why it is called a STABLE lean angle perhaps?!

 

:lol:

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Oh.

 

I just found the quote funny because in plain English it basically says, "any gyroscopic effect is offset or balanced by other forces at a stable lean angle."

 

Well, duh.

 

Hence why it is called a STABLE lean angle perhaps?!

 

:lol:

 

Racer,

Vittore knows his stuff...Motorcycle Dynamics is nothing but physical properties that pertains to a motorcycle in motion. I mean everything. I can't even begin to understand it but thought it would be fun to try some of the formulas....I just wanted to have a little fun with this discussion....I think that the event is a gyroscopic moment. From the time it takes you from going straight to Bam! Turn. Thats it. How much time does that take...milliseconds? So if one displaces their body for the turn the effects are limited! My phys ed teacher would be so proud.

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Racer,

Vittore knows his stuff...Motorcycle Dynamics is nothing but physical properties that pertains to a motorcycle in motion. I mean everything.

Cool. I didn't mean to imply otherwise.

 

I can't even begin to understand it but thought it would be fun to try some of the formulas....I just wanted to have a little fun with this discussion....

Me too. :)

 

I think that the event is a gyroscopic moment. From the time it takes you from going straight to Bam! Turn. Thats it. How much time does that take...milliseconds?

About 1-2 seconds for the average street rider. Perhaps 1/2 (0.5) seconds or 500 milliseconds for a fast racer.

 

So if one displaces their body for the turn the effects are limited! My phys ed teacher would be so proud.

Not sure I follow exactly what you mean here, but, hanging off isn't about increasing how fast you flick, it is mostly about reducing the lean angle you must carry through the turn for a given speed. Hence, if you are at max lean without hanging off, you can go faster through the turn if you do hang off. And, then, be able to complete the middle of the turn and lift up earlier to accelerate harder for the exit sooner.

 

And... hanging off before you flick is about stabilization for the flick process, not flicking faster.

 

For what it is worth, I am responding here to my interpretation or imputation of your interpretation of Vittore's words. Aside from the quote you posted, I haven't read them myself. And being that so much is missing from this thread, ie. Willie's posts, I'm not even sure what the premise re: gyroscopic effect here is.

 

r

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My gut says that the difficulty you are having understanding Vittore's words might have something to do with Italian being his native tongue and everything being translated with odd syntax and grammar. The JonesBoy post is a really good plain english wrap around the basic issues and/or (mis-)conceptions presented in this thread.

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I love this topic. One thing that is not debatable is that the physics is real, the question then remains does it have more of an effect than the geometry or is it a secondary force having little actual effect?

 

I pulled this out of the article because it is the exact point I depart the physics;

 

 

 

 

"This moment tends to tilt the motorcycle in the opposite direction from the steering motion; for this reason, to curve into a direction during fast driving, the rider exerts a quick rotation of the handlebars in the opposite direction.

 

The higher the velocity of handlebar rotation W, the higher will be the moment that tends to incline the motorcycle into the opposite direction."

 

 

 

 

When you turn the front tire it is the tire working against the ground driving in a new direction that causes the bike to lean, acting through the steering head and gravity pulling the now out of balance bike to the ground.

 

What proof can I offer? How about a race bike exiting a corner with the front wheel an inch off the ground and the front wheel turned having little effect? Being a wheelie expert I have long played with front wheel gyroscopic effect to turn the bike with the front wheel in the air. I can say with a high degree of certainty that if the tire is not touching the ground counter steering has little effect, or the exact and total effect of precession. With the tire on the ground the gyroscopic effects are completely secondary and never even catch up to the effect the tire creates in the lean angle of the bike.

 

Another point is if you take the gyroscopic effect as the end all for turning the bike how do you reconcile the fact that once the bike leans from the steering input the front wheel driven by trail will turn into the corner past center to balance the bike on the radius generating an even greater precessional force that should if you assume it leaned it in the first place immediately stand the bike up! DOOOOHHHHHH.

 

Will Eikenberry

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Hello, Willie!

 

Welcome back and thanks for posting!

 

I completely agree with you re: gyroscopic precession and its relationship to turning the bike.

 

That said, there seems to be an ongoing idea that gravity is responsible for a bike leaning into corner, ie. the wheels are steered out from under the bike and gravity causes the bike to simply fall into the turn. I do not accept this. There is exponentially more energy/force bound up in the mass and forward velocity of the bike than mere gravity at 9.8 m/s2. Especially when the inital motion is horizontal and rotational overall, ie. how much force can gravity exert in the horizontal at a lean angle of 2 degrees from vertical? 5 degrees? 10 degrees? Does the bike only start to flick fast at 30-45 degrees of lean angle? IMO, the forward momentum of the bike is the primary mover and the major force behind counter-steering that causes or intiates the lean and defines how fast a bike will lean over when counter-steered. This isn't to say that gravity has no effect, merely that the primary mover is forward momentum and a centrifugal type of effect. (Not really centrifugal to be pedantic, but, I will explain later.)

 

So... can a bike flick faster than gravity causes it to hit the ground if you simply let it fall from a stationary position? Even if you give it a head start by steering it out of its track? I believe so. I think that there is more than mere gravity and offset center of mass going on here. The faster or further you turn the bars, the faster the bike will lean or roll in the same way that a car will roll more/faster the harder you yank the steering wheel. Simply put, when you steer the bike left, it tries to continue in a straight line. Newton's Laws? This creates what would be a centrifugal effect with no centripetal force to control it (until you let go of the bars and it begins to track a radius at lean). The motorcycle, being inherently unstable (unlike a car with four wheels), there is nothing to stop the rollover, so, over it goes. However, a car will roll and lean the opposite way right up onto two wheels and further if you (counter-) steer it hard enough. Is that due to gravity?

 

Consider that the bike isn't simply falling. The top is moving more sideways than downwards until it reaches 45 degrees of lean angle. And that top moves far further than the wheels are steered out of track. So, forward velocity/momentum looks the likely pool of energy to me that is being tapped by the geometry. That forward velocity/momentum causesg the bike to fall off balance and z-rotate or initiate a "roll" or lean. Just like yanking the steering wheel in a car causes it to roll in the opposite direction. What other pool of potential energy are we tapping to initiate that horizontal component? Vertical gravity and height? I think not.

 

What do you think? Anyone?

 

Cheers,

racer

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I don't mean to shift the topic from gyro forces to steering the bike, but, this seems to be the salient point of the major premise, ie. gyro forces turn the bike. So...

 

A simplified analogy would be balancing a baseball bat and pulling the bottom out from under it about an inch vs. pushing the top over. I think this is the basic difference between the idea of a bike "falling over" due to gravity and "flicking over" due to counter-steering at speed.

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Hello, Willie!

 

Welcome back and thanks for posting!

 

I completely agree with you re: gyroscopic precession and its relationship to turning the bike.

 

That said, there seems to be an ongoing idea that gravity is responsible for a bike leaning into corner, ie. the wheels are steered out from under the bike and gravity causes the bike to simply fall into the turn. I do not accept this. There is exponentially more energy/force bound up in the mass and forward velocity of the bike than mere gravity at 9.8 m/s2. Especially when the inital motion is horizontal and rotational overall, ie. how much force can gravity exert in the horizontal at a lean angle of 2 degrees from vertical? 5 degrees? 10 degrees? Does the bike only start to flick fast at 30-45 degrees of lean angle? IMO, the forward momentum of the bike is the primary mover and the major force behind counter-steering that causes or intiates the lean and defines how fast a bike will lean over when counter-steered. This isn't to say that gravity has no effect, merely that the primary mover is forward momentum and a centrifugal effect.

 

So... can a bike flick faster than gravity causes it to hit the ground if you simply let it fall from a stationary position? Even if you give it a head start by steering it out of its track? I believe so. I think that there is more than mere gravity and offset center of mass going on here. The faster or further you turn the bars, the faster the bike will lean or roll in the same way that a car will roll more/faster the harder you yank the steering wheel. Simply put, when you steer the bike left, it tries to continue in a straight line. Newton's Laws? This creates a centrifugal effectn with no centripetal force to control it (until you let go of the bars and it begins to track a radius at lean). The motorcycle, being inherently unstable (unlike a car with four wheels), there is nothing to stop the rollover, so, over it goes. However, a car will roll and lean the opposite way right up onto two wheels and further if you (counter-) steer it hard enough. Is that due to gravity?

 

Consider that the bike isn't simply falling. The top is moving more sideways than downwards until it reaches 45 degrees of lean angle. And that top moves far further than the wheels are steered out of track. So, forward velocity/momentum looks the likely pool of energy to me that is being tapped by the geometry. That forward velocity/momentum is transformed to angular acceleration/centripetal force causing the bike to z-rotate or initiate a "roll" or lean. Just like yanking the steering wheel in a car causes it to roll in the opposite direction. What other pool of potential energy are we tapping to create that horizontal component? Vertical gravity and height? I think not.

 

What do you think? Anyone?

 

Cheers,

racer

 

The only problem with the idea is you would have to be holding the bike in the air and dropping it to get the idea of how fast gravity would move the bike. If you are assigning the rotation all to steering the front wheel then what is keeping the wheel on the ground as the center of mass is the fulcrum of rotation?

 

IMO knocking the front wheel out from under the bike is only allowing gravity to do its work and suck the bike down. It's when the steering input is released that centrifugal force is generated to balance out the gravity at the new lean angle, or you drive the bike right into the ground with the steering.

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I need to preface this post by noting that I misused the word centripetal when I meant centrifugal in the last paragraph two posts back and inaccurately used centrifugal in my last post. I will edit it before some mechanical engineer or physics expert bites my head off for it. My bad.

 

The only problem with the idea is you would have to be holding the bike in the air and dropping it to get the idea of how fast gravity would move the bike.

 

Actually, all mass falls at the same rate, so, a golf ball would do to isolate the vertical acceleration offered by gravity. Based on the known acceleration of standard Earth normal gravity, ie. 9.8m/s/s, one could extrapolate a one meter fall at perhaps 1/10 of a second or a little more. But, the point is that, as we both said, the bike isn't just falling, it is rotating on the z-axis which must, IMO, include a horizontal component of force to initiate as the front wheel doesn't get very far out of track before you are over. IMO, the closest practical test to isolate the effect of gravity from forward momentum in a similar scenario would be to simply allow a motorcycle to tip over from a stationary position. Perhaps cocking the front wheel first to approximate the counter-steered position?

 

If you are assigning the rotation all to steering the front wheel then what is keeping the wheel on the ground as the center of mass is the fulcrum of rotation?

 

I disagree that the center of mass is the fulcrum of z-axis rotation for the machine as it leans over. If you watch a video of an oncoming bike being counter-steered, you can clearly see that it only moves a few inches off track. If the CoM was the fulcrum, the wheels would move as far off track as the top of the bike. I believe that the contact patch is the fulcrum that our moment arm attempts to rotate from in this instance. However, turning the front wheel causes the bike to move off track as it initially attempts to track in the direction you steer before the bike leans in.

 

IMO knocking the front wheel out from under the bike is only allowing gravity to do its work and suck the bike down. It's when the steering input is released that centrifugal force is generated to balance out the gravity at the new lean angle, or you drive the bike right into the ground with the steering.

 

 

Well, I think we are doing more than knocking the front wheel out from under the bike. I think we are attempting to steer the bike and the front wheel tracks the way you steer before the bike leans in. And, for the pedantic minded, to be scientifically accurate, when the input is released, a centripetal force is created at the contact patches as the bike begins to track an arc after it leans which creates a centrifugal effect in the opposite direction. And opposite of the one that knocks it over as the bike attempts to continue in a straight line when you turn the bars. Just like a car. Turn right hard enough and you're going to have a lap full of passenger. IMO, this is essentially the same thing as what happens to the bike when you steer it except that there is nothing to catch it until you let go of the bars and it begins to track an arc. I guess, technically, it isn't a centrifugal effect if there is no centripetal force. So, again, for the engineers out there, to be scientifically accurate, the bike merely rolls over as it attempts to continue straight, whereas, the interior surface of your car door holding the passenger from falling out in a left turn provides the centripetal force there. The bottom line, IMO, is that it is the same type of process and forces at work, except that the bike doesn't have four wheels, so it falls over. But, driven by the same type of force that drives that passenger against the car door.

 

I apologize for posting in such a hurry and not taking more time to explain and clarify the more scientific concepts for the laypersons here. I will return when I have more time and try to do a better job of this. Just to reiterate, I think gravity DOES play a part in the bike rolling over. But my gut says that forward momentum plays a significant role in initiating that roll. I will try to think of a good experiment to isolate THAT idea.

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Racer,

Someone once told me, “People like to act like they know it all because it makes them feel important.”

Any thoughts on this?

 

-Jim

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Racer,

Someone once told me, “People like to act like they know it all because it makes them feel important.”

Any thoughts on this?

 

-Jim

 

Yes, Jim.

 

Someone once told me that people who feel small and weak like to knock other people down because it makes them feel big and strong.

 

Do you have any thoughts related to the thread topic?

 

racer

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Well all I have to say about that is I do have a conceptual knowledge about how a bike works and can explain it without subterfuge and misdirection in simple terms ( as I am a Layman) without need to go into a pedantic ramble that only confuses the issue with esoteric terms.

 

That being said, Physics is a great piece of the puzzle but it is only one part. it is not the end all and it does not discount the effect of geometry on a single track vehicle. The physics of it is in fact a way to understand " WHY" geometry works.

 

So for now I will still have to rely on what is demonstrable as I find the "scientific" explanation induces drowsiness and I have machinery to operate.

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So for now I will still have to rely on what is demonstrable as I find the "scientific" explanation induces drowsiness and I have machinery to operate.

And I thought I was the only one

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So for now I will still have to rely on what is demonstrable as I find the "scientific" explanation induces drowsiness and I have machinery to operate.

And I thought I was the only one

 

that was funny, I laughed out loud.

 

Cobie

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Well all I have to say about that is I do have a conceptual knowledge about how a bike works and can explain it without subterfuge and misdirection in simple terms ( as I am a Layman) without need to go into a pedantic ramble that only confuses the issue with esoteric terms.

 

Excuse me? What?

 

Your response is to characterize and blame my writing style to allege some inability on your part to grasp the simple and clearly demonstrable concept of lateral G force (turn the wheel of your car and your weight goes sideways)? And then to direct an unsupported ad hominem attack and accusation of dishonesty and deception at my person while ignoring the points and ideas I presented?

 

"Hey, look over there at that 'pedantic ramble' (yawn). It's so intentionally tricky and twisted that it's making me drowsy. I'm a wheelie expert and a coach, and I suggest everyone ignore it. All science can tell us is the 'why' anyway."

 

Are you kidding me? Misdirection and subterfuge? Who? :lol:

 

Let's be clear... you said you "love this topic". And then you opened the door and invited discussion of "esoteric" scientific concepts with your comments re: gyroscopic precession and gravity. The whole thing was your bloody idea, mate! I naturally assumed you were honestly representing yourself and your interests.

 

My bad.

 

Then again, perhaps I misunderstood you and the topic you love is merely gyroscopic precession not being responsible for turning a bike... because you believe you have the answer to that.

 

Just one question...

 

If you aren't interested in science or learning (and can't be bothered to ask for clarification of a specific point you didn't get), why bother reading a thread that is dedicated to science? Much less say that you are interested and then turn around and post negative, derogatory and troll-like remarks mocking the thread topic and posters who disagree with you?

 

What's up with that?

 

Whatever.

 

Have a better one.

 

racer

 

 

 

PS - For the record, it was not my intention to label you (or anyone) in particular as a "layman". Nor do I consider the term any sort of an insult. However, I do consider myself to be a layman, albeit one who studies and enjoys learning something new. If you assumed I was trying to put down (or talk down to) people by using that term if they didn't agree with me, then, I apologize for the misunderstanding. That wasn't my intention at all.

 

My only intention was (and still is) to learn and to help other people in whatever way I can. That said, it just happens that this is my favorite topic and I do love discussing it. I'm not trying to "win" anything or even to be "right". I'm happy to be wrong. I love being wrong. Being wrong is the beginning of all learning. I do not believe that I know everything or that mine is the final word and I would love to learn something new today. Hence, why I qualified all of my ideas in this thread with "in my opinion" (IMO) or "I think" or "I believe", etc. I'm not that guy who said, "it seems" is a nice way of saying "you are wrong". I was sincerely hoping for some genuine, on-topic thoughts or ideas from anyone who is actually interested in this subject... as I indicated at the end of my first post.

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Hey Racer

 

A couple of things first, I said "I" am a layman, I am also a red neck, white bread, cracker. I take no insult in any of those. And yes I do like talking about this stuff though you can and did go too far outside my understanding of the "math", and no a dictionary would not be enough to follow you.

 

I am not a coach, I am a mechanic who knows how to ride and my expertice is in the practical application not the theory. I was tought to ride, I am a natual mechanic and fabricator though.

 

When I said I love this topic, I do, in spite of the percived insult to you. I really did need to go and operate some equipment.

Will

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Hey Racer

 

... yes I do like talking about this stuff though you can and did go too far outside my understanding of the "math", and no a dictionary would not be enough to follow you.

 

Will

 

OK. I can handle that.

 

It would help me if you could say more about where I lost you. For instance, I presented a "plain English" example/analogy of a four-wheeled vehicle rolling opposite to the direction of the turn when steered into a corner, ie. turn left and your passenger is pushed into the door and the vehicle tilts that way, too. Are you familiar with this experience? (I assume you are, but, better to be certain everyone is on the same page.)

 

PS - I live in the US and our steering wheels are on the left side of the car as we drive on the right side of the road. Hence, drivers in countries that drive on the left side of the road will steer right to push their front seat passengers up against the door.

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Racer--I read what Will had said, and I didn't take as you did. I'm not going to re-hash this, but glad you guys have sorted this out. I do sometimes also get lost with the physics theory, I keep hoping guys will get some drawings or links up here to put a little "mass" to the subjects.

 

Best,

Cobie

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OK...

 

Will, Cobie, Jay, and anyone else...

 

I think it is safe to assume that pretty much everyone here is familiar with the experience I described above and is with me so far. So, I think the next step is to agree or understand why that happens. Here comes the science.

 

Most folks have probably heard of Issac Newton, if not his Three Laws of Motion. In any case, Newton's First Law defines a property of motion called "inertia". In a nutshell, the first law defines inertia as the tendency for a body at rest to remain at rest or a body in uniform motion to remain in uniform motion until acted upon by an outside or unbalanced force. ("Uniform", in this case, would indicate a consistent type of motion, like a straight line.)

 

So, driving in a straight line, if you turn the steering wheel of your car (imparting an outside force), the mass of you, your passenger and the car itself will try to keep going in a straight line. We "force" the car to change direction, but, everything inside, and even the car itself, resists that change and tries to keep going straight.

 

Taking it to the next step, if we are driving a relatively taller vehicle, like a van or a truck (especially loaded up high with cargo), that "top heavy" vehicle has a higher "center of gravity" and will have a tendency to lean more or even to tip over if we steer it hard enough. As I know you are also a professional truck driver, Will (as well as a mechanic), I'm betting you are familiar with this concept, too.

 

This concept would also apply to a vehicle that is more narrow, rather than simply taller, as it is the relationship or ratio of height (specifically of center of gravity) to width that defines the inherent stability of any vehicle (or body) in motion. So, if your vehicle is taller and/or has a more narrow wheelbase, it will be less stable. Sports cars have a relatively wide wheel base combined with a low center of gravity for increased stability.

 

OK... last step.

 

Now, here is where it gets a little tricky... because of gravity (and the sticky nature of rubber), there is "friction" created between the tires and the road. Friction is what causes the wheels to stick to the road and allows the vehicle to go in the direction you steer it. And, because the wheels stick when you turn the steering wheel, the energy of the vehicle trying to go straight causes it to "roll" or lean sideways (rather than slide). BUT, to be very clear, it is the FRICTION that allows that to happen.

 

Even without gravity, if the wheels were sticking to the road because of say magnetism, the car/vehicle would still lean toward the outside when steered into a corner. Same thing if your butt was glued to the seat with superglue rather then gravity. Your body in the car would still lean. The point is that it is FRICTION that creates a fulcrum and lever (or moment arm) acted upon by the force of inertia/momentum that allows or causes the leaning, NOT gravity sucking your body down.

 

Finally...

 

Ultimately, the extreme example of a vehicle with the most narrow wheelbase is a motorcycle!

 

 

I will stop here as it seems a good place to break and I have spent most of the afternoon of my day off working on this and I need to get some other stuff done. I hope those who were made drowsy will dedicate at least a little bit of time and effort to try to follow along and come up with specific questions if there is something that isn't clear.

 

 

Thanks,

 

racer

 

 

 

PS - pursuant to the term "momentum" and "moment arm", I should define a couple more terms. A body in motion has "momentum". Momentum is essentially a way to measure inertia or tendency for a body to remain in motion in terms of potential energy by measuring and multiplying the mass of the body and its velocity. In other words, the heavier and faster your vehicle, the more momentum it has and the greater its tendency to remain in motion, and, the more force over time... or energy... it takes to stop it. So, in practical terms, it takes more force and/or more time to stop a heavy truck than a small car, ie. more brakes and/or greater stopping distance.

 

There are basically two types of momentum. "Linear" momentum which I described above, and, "angular" momentum. Linear momentum is a property of a body moving in a straight "line", hence, the word linear. Angular momentum is property of a body moving in a circular fahion or rotating/pivoting. I don't know if it is proper to call a moment arm a lever, or the point about which it rotates a fulcrum. However, the swingarm on a motorcycle is a good example of an arm that rotates around an axis at the swingarm pivot. I will do some more research to find out what is proper so I don't steer anyone in the wrong direction by posting bad data.

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I hate using an auto or aircraft as a reference for what is going with a motorcycle.

 

I live by Newton's laws.

 

I know there is a point in there somewhere and it seems to me what you are saying is it's not gravity but what it creates that is responsible for the bike leaning?

 

I said earlier "knock the front end out from under the bike" and what I am saying is by turning the front wheel away from the direction of travel the force is transmitted through the steering head and at the same time the mass is not turning yet but is being made to lean by the twist induced to the steering head and gravity pulling down on it as the front wheel isn't under it in a supporting way.

 

A couple of small points; the forks have sag and can extend away from the steering head as the wheel drives in the new (steered) direction, and do.

 

The rear of the bike counter steers too, goes off track in the direction of the steering input. This is caused as the mass rotates around the center of mass to a degree. The tires are not fulcrum; it is higher and can be seen in video.

 

I think this is where we disagree.

 

Will

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I think we agree on about 85% of what you said. However, I will need more time to study the points of your theory I am not clear on and craft a skillful interrogative to clarify the other 15% if necessary. I am off to bed now to rest up for 40 hours of work in the next 3 days.

 

Cheers

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I live in the UK, drive on the left hand side of the road and steering wheel is at the right hand side, what way do I have to steer to make my hot pasenger land on my lap? lol only joking!

l understand most of what you guys are talking about, but I cant see how its easier to use a different type of vehicle as an example for the vehicle we all share an interest in! MOTORBIKES!

First of all they are not the vehicle with the most narrow wheelbase since wheelbase represents the distance between two wheels at that point we only have one wheel, they probably do however have the shortest wheelbase and sportbikes have particularly short wheel base to allow them to steer quicker! maybe time to go back to bacics! and as a pre warning I am not a scientist, I am entering a discussion, not an arguement!

If it takes 1 tenth of a secnd for an object to fall 1 metre, if gravity pulls the bike down, wouldn't it be possible to steer your bike to the desired lean angle in less than 0.1 of a second, can anyone steer this fast? Say from upright to 45 degrees probably a distance of less than half a metre. Take a sportsbike, at 20 mph it is easy to steer to 45 degrees but what about when you go faster say 60 mph, does it require more effort to turn? what kind of effort does it need? is it push the bars harder? or push the bars faster? or both?

 

Sorry thats alot of little questions but I'm trying to bring this thread back to bikes, and understand how to conrol the gyroscope that is my front wheel, see I always thought the faster a gyroscope spun the more effort required to move it!

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