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#81
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On 2/12/2014 5:14 PM, Poco Loco wrote:
On Wed, 12 Feb 2014 16:21:26 -0500, KC wrote: On 2/12/2014 3:52 PM, Poco Loco wrote: On Wed, 12 Feb 2014 15:15:41 -0500, KC wrote: On 2/12/2014 12:35 PM, Poco Loco wrote: On Wed, 12 Feb 2014 11:44:07 -0500, KC wrote: On 2/12/2014 11:20 AM, Poco Loco wrote: On Wed, 12 Feb 2014 10:33:01 -0500, KC wrote: On 2/12/2014 10:06 AM, Mr. Luddite wrote: On 2/12/2014 9:42 AM, Poco Loco wrote: On Wed, 12 Feb 2014 09:06:41 -0500, BAR wrote: In article , __ says... Mr. Luddite wrote: On 2/9/2014 6:25 PM, Poco Loco wrote: On Sun, 9 Feb 2014 15:03:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 4:30:04 PM UTC-6, John H. wrote: On Sun, 9 Feb 2014 13:31:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 7:31:31 AM UTC-6, F.O.A.D. wrote: I'd love to have one of these... http://www.youtube.com/watch?v=U7mTwM7afQA how about something like this? http://thekneeslider.com/1937-front-...cle-prototype/ Looks like something Moto Guzzi made during the war. "Goose" probably tries something like that too, but this is French, and the French at that time were known to be great tinkerers, with results to match. Yeah, I should have said it looks like something Guzzi *could* have made during the war. Something like this: http://www.youtube.com/watch?v=4cOlS_ShXf4 Here's an idea for Scott: (warning - contains boating content) http://www.elrellano.com/videos_online/8146/barca-a-motor.html No steering unless that rowboat has a bow thruster. Just like a motor cycle, you just lean into the turn to make it go that way. No, leaning doesn't make it turn. Leaning enables the motorcycle to be kept more vertical when turning. Pushing on the handlebar makes you turn. Push left, go left. Push right, go right. Countersteering. Heh. I just mentioned to Scott about that. Those who don't ride will think it's weird. They think it should turn like a car. Yes, counter steering but again, it's not the fastest way around the corner ![]() It's the only way around the corner, at speed, on a motorcycle. I am beating myself up and I can't think of any place on the track where counter steering is faster... https://www.facebook.com/photo.php?fbid=10202016412913497&set=a.10202016402 113227.1073741828.1281248494&type=3&theater Here is Jess setting up for a corner... notice she is turning left, and her bars are slightly left.. If she let her back tire slide out more (blowing the corner) the bike would have to stand back up and the back tire come back in line to get out of the corner... don't know if that makes any sense. I have a video I could find later of two riders me and Jess study. One came though the corner right (her mentor) and the guy behind counter steered through and lost two seconds in the corner... Letting the back tire 'slide out more' is not a method of riding for anyone but dirt bikers. When she initiated the turn to the left, she did it by pushing on the left bar or pulling on the right bar. Once the bike started leaning (and turning) she can slide all she wants. I think what she is doing in the picture is coming out of a turn. So she's pushing on the right bar to straighten the bike up (or pulling on the left bar). Looking at the tracks in the dirt also shows that she's through the turn. That picture is in the first 30 feet of the turn.. and no. She doesn't have to push the left down to initiate the turn. Some turns she comes into airborne and she already has the bars turned in the direction of the turn... I see completely what you guys are talking about. I have had a mc licence since '76 and always thought that way... Until I started training Jess. She comes into a corner and throws her weight over the bike.. but pushes both bars down... the outside bar further... never the inside bar, never let that rear tire get outside of the radius of the front tire...... Just the way it is. ![]() inside bar, the rear tire kicks outside the radius of the inside tire. now you have thrust pushing askew from the direction of the bike... we calle it "wash out" or "blowing the berm".. draw it out, put arrows for thrust.. You will see... Uh-huh. I just hope Jess, while on pavement going at speed, doesn't ever push left to go right. Something will get broke. OK, let's go from there.. When you are countersteering on the street, by design the thrust of the rear tire and front tire are not in sync with the direction of the turn.. So which tire do you slide? Just so you don't think I'm lying to you: http://en.wikipedia.org/wiki/Countersteering Countersteering is the technique used by single-track vehicle operators, such as cyclists and motorcyclists, to initiate a turn toward a given direction by momentarily steering counter to the desired direction ("steer left to turn right"). A more accurate term is deliberate countersteering when employed by a rider, though it is often shortened to just countersteering. To negotiate a turn successfully, the combined center of mass of the rider and the single-track vehicle must first be leaned in the direction of the turn, and steering briefly in the opposite direction causes that lean.[1] This technique does not apply to conventional multiple-tracked vehicles such as trikes or sidecar-equipped bicycles and motorcycles. How it works[edit] A single-track vehicle such as a bicycle or a motorcycle is an inverted pendulum—it will fall over unless balanced. The technique used by cyclists and motorcyclists to initiate turning in a given direction is to first apply a steering torque in the opposite direction. For example, if a turn to the left is desired, it is started by applying a torque on the handlebars to the right. This causes the front wheel to rotate about the steering axis to the right and the front tire will generate forces in the contact patch to the right. The machine as a whole steers to the right briefly, and because the forces in the contact patch are at ground level, this pulls the wheels "out from under" the bike to the right and causes it to lean to the left. Then the rider, or in most cases, the inherent stability of the bike provides the steering torque necessary to rotate the front wheel back to the left and in the direction of the desired turn. Finally, the bike begins a turn to the left.[11] It is often boiled down to "push left to go left". While this appears to be a complex sequence of motions, it is performed by every child who rides a bicycle. The entire sequence goes largely unnoticed by most riders, which is why some assert that they do not do it. It is often claimed that two-wheeled vehicles can be steered using only weight shifts. While this is true for small "trim" inputs to direction, complex maneuvers are not possible using weightshifting alone because even for a light machine there is insufficient control authority.[12] Although on a sufficiently light bike (especially a bicycle), the rider can initiate a lean and turn by shifting body weight,[6] there is no evidence that complex maneuvers can be performed by bodyweight alone.[9] It is also important to distinguish the steering torque necessary to initiate the lean required for a given turn from the sustained steering torque and steering angle necessary to maintain a constant radius and lean angle until it is time to exit the turn. The initial steer torque and angle are both opposite the desired turn direction. The sustained steer angle is in the same direction as the turn. The sustained steer torque required to maintain that steer angle is either with or opposite the turn direction depending on forward speed, bike geometry, and combined bike and rider mass distribution. Deliberate countersteering is necessary to adjust the angle of lean of a bike and works in the opposite sense to the handlebar input while conventional steering in the direction of the turn is used to negotiate the turn. Need to lean to turn[edit] A bike can negotiate a curve only when the combined center of mass of bike and rider leans toward the inside of the turn at an angle appropriate for the velocity and the radius of the turn: \theta =\arctan \left({\frac {v^{2}}{gr}}\right) where v is the forward speed, r is the radius of the turn and g is the acceleration of gravity.[6] Higher speeds and tighter turns require greater lean angles. If the mass is not first leaned into the turn, the inertia of the rider and bike will cause them to continue in a straight line as the tires track out from under them along the curve. The transition of riding in a straight line to negotiating a turn is a process of leaning the bike into the turn, and the most practical way to cause that lean (of the combined center of mass of bike and rider) is to move the support points in the opposite direction first.[13] The rider can shift his weight of course, but any force used to move one way laterally pushes the bike laterally the opposite direction with equal force. That makes the bike lean (and can affect the steering), but it does not change the combined center of mass of bike and rider. Lean by countersteering[edit] When riding a bicycle or a motorcycle, deliberate countersteering is a method of initiating a turn by a small, momentary turn of the front wheel, usually via the handlebars, in the opposite (counter) direction. This moves the pivot point (the wheels' contact patches) out from under the center of mass to establish the lean angle for a turn. While exploitable at all speeds, the need to deliberately countersteer becomes more noticeable as speed increases. Hence, to turn to the right, the rider first throws the bike off balance by momentarily pointing the front wheel slightly to the left. The center of mass of the bike plus rider will continue in a straight line, but the contact patches of the tires move to the left with respect to this straight line. Once lean is achieved[edit] As the desired angle is approached, the front wheel must usually be steered into the turn to maintain that angle or the bike will continue to lean with gravity, increasing in rate, until the side contacts the ground. This process often requires little or no physical effort, because the geometry of the steering system of most bikes is designed in such a way that the front wheel has a strong tendency to steer in the direction of a lean. The actual torque the rider must apply to the handlebars to maintain a steady-state turn is a complex function of bike geometry, mass distribution, rider position, tire properties, turn radius, and forward speed. At low speeds, the steering torque necessary from the rider is usually negative, that is opposite the direction of the turn, even when the steering angle is in the direction of the turn. At higher speeds, the direction of the necessary input torque often becomes positive, that is in the same direction as the turn.[14] Adjusting or exiting a turn[edit] Once in a turn, deliberate countersteering is again required to make changes to its shape. The only way to decrease the radius at the same speed is to increase the lean angle, and the most effective way to increase the lean angle, is again to momentarily steer opposite to the direction of the curve. To the untrained, this can be extremely counter-intuitive. To exit a turn, a deliberate countersteer by momentarily steering further in the direction of the turn will tilt the bike back upright. At low speeds[edit] At low speeds countersteering is equally necessary, but the countersteering is then so subtle that it is hidden by the continuous corrections that are made in balancing the bike, often falling below a just noticeable difference or threshold of perception of the rider. Countersteering at low speed may be further concealed by the ensuing much larger steering angle possible in the direction of the turn. Unthinking behavior[edit] Countersteering is indispensable for bike steering. Most people are not aware that they employ countersteering when riding their bike any more than they are aware of the physics of walking. They have learned to apply the required countersteering without thinking. As is well known in bicycle racing, the countersteering phenomenon becomes evident when there is an obstacle preventing the wheel from countersteering (e.g., when closely overlapping wheels or riding very close to a curb). In these situations, the way to initiate a turn with the handlebars away from the obstacle is to countersteer towards obstacle to avoid crashing into it.[13] Lack of understanding of this principle leads to accidents in novice bicycle races. Gyroscopic effects[edit] One effect of turning the front wheel is a roll moment caused by gyroscopic precession. The magnitude of this moment is proportional to the moment of inertia of the front wheel, its spin rate (forward motion), the rate that the rider turns the front wheel by applying a torque to the handlebars, and the cosine of the angle between the steering axis and the vertical.[14] For a sample motorcycle moving at 22 m/s (50 mph) that has a front wheel with a moment of inertia of 0.6 kgm2, turning the front wheel one degree in half a second generates a roll moment of 3.5 Nm. In comparison, the lateral force on the front tire as it tracks out from under the motorcycle reaches a maximum of 50 N. This, acting on the 0.6 m (2 ft) height of the center of mass, generates a roll moment of 30 Nm.[14] While the moment from gyroscopic forces is only 12% of this, it can play a significant part because it begins to act as soon as the rider applies the torque, instead of building up more slowly as the wheel out-tracks. This can be especially helpful in motorcycle racing.[14] No hands[edit] Oh, so it's something you do once in a while.. I get it.. So, I can push my right bar to turn left if I want to... got it... |
#82
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posted to rec.boats
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On 2/12/2014 5:23 PM, Poco Loco wrote:
On Wed, 12 Feb 2014 17:07:52 -0500, KC wrote: On 2/12/2014 4:57 PM, Bill McKee wrote: On 2/12/14, 1:46 PM, KC wrote: On 2/12/2014 4:37 PM, Mr. Luddite wrote: On 2/12/2014 4:10 PM, KC wrote: On 2/12/2014 3:36 PM, Mr. Luddite wrote: On 2/12/2014 3:05 PM, KC wrote: On 2/12/2014 2:47 PM, Poco Loco wrote: On Wed, 12 Feb 2014 13:59:51 -0500, HanK wrote: On 2/12/2014 11:37 AM, KC wrote: On 2/12/2014 11:23 AM, HanK wrote: On 2/12/2014 10:40 AM, KC wrote: On 2/12/2014 10:31 AM, KC wrote: On 2/12/2014 10:04 AM, Mr. Luddite wrote: On 2/12/2014 9:36 AM, KC wrote: On 2/12/2014 9:17 AM, Mr. Luddite wrote: On 2/12/2014 8:09 AM, Poco Loco wrote: On Tue, 11 Feb 2014 20:27:03 -0500, Earl__ wrote: Mr. Luddite wrote: On 2/9/2014 6:25 PM, Poco Loco wrote: On Sun, 9 Feb 2014 15:03:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 4:30:04 PM UTC-6, John H. wrote: On Sun, 9 Feb 2014 13:31:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 7:31:31 AM UTC-6, F.O.A.D. wrote: I'd love to have one of these... http://www.youtube.com/watch?v=U7mTwM7afQA how about something like this? http://thekneeslider.com/1937-front-...cle-prototype/ Looks like something Moto Guzzi made during the war. "Goose" probably tries something like that too, but this is French, and the French at that time were known to be great tinkerers, with results to match. Yeah, I should have said it looks like something Guzzi *could* have made during the war. Something like this: http://www.youtube.com/watch?v=4cOlS_ShXf4 Here's an idea for Scott: (warning - contains boating content) http://www.elrellano.com/videos_online/8146/barca-a-motor.html No steering unless that rowboat has a bow thruster. That boat is a high technology marvel incorporating 'eyeball sensormatic rotational assist'. Where you look is where you go. A sign on the bow says, "Don't look at women when operating this vessel." Sometimes the sign gets torn away. When I was a kid I had a 12' aluminum boat with a little 3hp outboard. I'd tighten the tension on the steering so the motor wouldn't move, sit in the middle seat and steer just by leaning towards one side or the other. Worked fine in large ponds. Somebody said "like a motorcycle"... But if you simply lean a motorcycle and don't turn the wheel, it will still go straight... Just sayin'. No, you have to tip the boat. Speaking of motorcycles, ever try this? Ride going straight ahead and push your *left* handlebar forward gently and see which way you turn. Then try with the *right* handlebar. Yeah, that's how she takes every turn... Reverse steer. Add in breaking loose the rear tire and you are starting to have some fun however, if you do though, you are losing time going sideways instead of forward ![]() Just reread that... I should say she counter steers when the suspension or body position is off... But it's not the fastest way around the track... What is the fastest way around the track? Ok, the fastest way involves being efficient in the corners. If you are countersteering n a corner, you are standing the bike too high, and the drive wheel is not taking the shortest distance around the corner. In racing terms, you blew out the birm.. It's not efficient to have that back tire way out there cause then it takes time to bring it back... How can you be efficient in the corners? Balance.. Keep both tires in as close to the same radius as the other. You want the front tire pointing as close to the direction of thrust from the rear tire as possible. If you are "countersteering" you are losing forward thrust and burning off forward thrust... Geeze. I'll never enjoy a warm summer evening cruise down to the Cape again. :-) Sure you will. Like you said you are not racing... I said before I get the whole thing about getting into a corner and even counter steering. The looser you are, the more you do it too.... but it's still not the most efficient way to make a corner... You guys are all supposed to be sailors.. Draw the thing out and draw out the thrust and resistance lines... you will see what I am talking about... Anyway, I have a good drawing that I can put up later. For now I will say there are a couple other things we do to make the bike corner better. One in particular is to gently pull the front brake in and dip the front end which shortens the turning radius and increases the angle of the front suspension more upright to turn.. (more like a tricycle)... Even dipping the front end a couple inches reduces the bike length by as much as an inch and can change the rake of the front end 8-10 degrees... But again, you are not racing. If I was you I would be countersteering all the way to the beach. I know how good it feels and I wouldn't be "racing" on the street anyway ![]() Phew. I was getting worried there. It's sorta hard to steer a 850lb Harley with the back tire. Even if I could, it would probably be the last turn I ever made. Yup... Imagine so. I had times where I slid my Honda into a countersteer slide when I was younger. Never intentionally though ![]() weight of your bike too... Hell, no wonder I did not win every race with my Vette. I was drifting corners at times. The old Laguna Course, turn 2 was always able to go faster than you figured as the apex of the corner started up hill. Loading the suspension and increasing traction. Turn 3 was a very highspeed turn and you drifted it at about 130 mph. Here's my point... You drifted that corner at 130, scrubbing forward speed off in the drift... How about I come behind you in a formula racer that can take the corner without countersteering and breaking traction.. how fast do you think that car might make that corner with all the hp pushing it forward?? There's no such thing as 'countersteering' an automobile. Sure, it's called "drifting"... |
#83
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posted to rec.boats
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On 2/12/2014 5:27 PM, Mr. Luddite wrote:
On 2/12/2014 5:16 PM, Poco Loco wrote: On Wed, 12 Feb 2014 13:57:17 -0800, Bill McKee wrote: On 2/12/14, 1:46 PM, KC wrote: On 2/12/2014 4:37 PM, Mr. Luddite wrote: On 2/12/2014 4:10 PM, KC wrote: On 2/12/2014 3:36 PM, Mr. Luddite wrote: On 2/12/2014 3:05 PM, KC wrote: On 2/12/2014 2:47 PM, Poco Loco wrote: On Wed, 12 Feb 2014 13:59:51 -0500, HanK wrote: On 2/12/2014 11:37 AM, KC wrote: On 2/12/2014 11:23 AM, HanK wrote: On 2/12/2014 10:40 AM, KC wrote: On 2/12/2014 10:31 AM, KC wrote: On 2/12/2014 10:04 AM, Mr. Luddite wrote: On 2/12/2014 9:36 AM, KC wrote: On 2/12/2014 9:17 AM, Mr. Luddite wrote: On 2/12/2014 8:09 AM, Poco Loco wrote: On Tue, 11 Feb 2014 20:27:03 -0500, Earl__ wrote: Mr. Luddite wrote: On 2/9/2014 6:25 PM, Poco Loco wrote: On Sun, 9 Feb 2014 15:03:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 4:30:04 PM UTC-6, John H. wrote: On Sun, 9 Feb 2014 13:31:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 7:31:31 AM UTC-6, F.O.A.D. wrote: I'd love to have one of these... http://www.youtube.com/watch?v=U7mTwM7afQA how about something like this? http://thekneeslider.com/1937-front-...cle-prototype/ Looks like something Moto Guzzi made during the war. "Goose" probably tries something like that too, but this is French, and the French at that time were known to be great tinkerers, with results to match. Yeah, I should have said it looks like something Guzzi *could* have made during the war. Something like this: http://www.youtube.com/watch?v=4cOlS_ShXf4 Here's an idea for Scott: (warning - contains boating content) http://www.elrellano.com/videos_online/8146/barca-a-motor.html No steering unless that rowboat has a bow thruster. That boat is a high technology marvel incorporating 'eyeball sensormatic rotational assist'. Where you look is where you go. A sign on the bow says, "Don't look at women when operating this vessel." Sometimes the sign gets torn away. When I was a kid I had a 12' aluminum boat with a little 3hp outboard. I'd tighten the tension on the steering so the motor wouldn't move, sit in the middle seat and steer just by leaning towards one side or the other. Worked fine in large ponds. Somebody said "like a motorcycle"... But if you simply lean a motorcycle and don't turn the wheel, it will still go straight... Just sayin'. No, you have to tip the boat. Speaking of motorcycles, ever try this? Ride going straight ahead and push your *left* handlebar forward gently and see which way you turn. Then try with the *right* handlebar. Yeah, that's how she takes every turn... Reverse steer. Add in breaking loose the rear tire and you are starting to have some fun however, if you do though, you are losing time going sideways instead of forward ![]() Just reread that... I should say she counter steers when the suspension or body position is off... But it's not the fastest way around the track... What is the fastest way around the track? Ok, the fastest way involves being efficient in the corners. If you are countersteering n a corner, you are standing the bike too high, and the drive wheel is not taking the shortest distance around the corner. In racing terms, you blew out the birm.. It's not efficient to have that back tire way out there cause then it takes time to bring it back... How can you be efficient in the corners? Balance.. Keep both tires in as close to the same radius as the other. You want the front tire pointing as close to the direction of thrust from the rear tire as possible. If you are "countersteering" you are losing forward thrust and burning off forward thrust... Geeze. I'll never enjoy a warm summer evening cruise down to the Cape again. :-) Sure you will. Like you said you are not racing... I said before I get the whole thing about getting into a corner and even counter steering. The looser you are, the more you do it too.... but it's still not the most efficient way to make a corner... You guys are all supposed to be sailors.. Draw the thing out and draw out the thrust and resistance lines... you will see what I am talking about... Anyway, I have a good drawing that I can put up later. For now I will say there are a couple other things we do to make the bike corner better. One in particular is to gently pull the front brake in and dip the front end which shortens the turning radius and increases the angle of the front suspension more upright to turn.. (more like a tricycle)... Even dipping the front end a couple inches reduces the bike length by as much as an inch and can change the rake of the front end 8-10 degrees... But again, you are not racing. If I was you I would be countersteering all the way to the beach. I know how good it feels and I wouldn't be "racing" on the street anyway ![]() Phew. I was getting worried there. It's sorta hard to steer a 850lb Harley with the back tire. Even if I could, it would probably be the last turn I ever made. Yup... Imagine so. I had times where I slid my Honda into a countersteer slide when I was younger. Never intentionally though ![]() weight of your bike too... Hell, no wonder I did not win every race with my Vette. I was drifting corners at times. The old Laguna Course, turn 2 was always able to go faster than you figured as the apex of the corner started up hill. Loading the suspension and increasing traction. Turn 3 was a very highspeed turn and you drifted it at about 130 mph. This countersteering applies only to two wheel, single track vehicles! This discussion is heading back to the debate we had a while back about traction and what can take a corner faster ... a four wheeled car or a motorcycle. The "rolling cone" analogy Bill brought up applies to four wheeled vehicles where the outside wheels have to turn faster than the inside wheels in a turn. Really doesn't apply to a two wheeled motorcycle. The other thing is that Scott's style and techniques used in moto-cross racing has little to do with riding a street bike down a winding country road. Yes, but as with the google link I posted. You can turn a motorcycle, without countersteering. Street, or track... |
#84
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posted to rec.boats
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On 2/12/14, 2:07 PM, KC wrote:
On 2/12/2014 4:57 PM, Bill McKee wrote: On 2/12/14, 1:46 PM, KC wrote: On 2/12/2014 4:37 PM, Mr. Luddite wrote: On 2/12/2014 4:10 PM, KC wrote: On 2/12/2014 3:36 PM, Mr. Luddite wrote: On 2/12/2014 3:05 PM, KC wrote: On 2/12/2014 2:47 PM, Poco Loco wrote: On Wed, 12 Feb 2014 13:59:51 -0500, HanK wrote: On 2/12/2014 11:37 AM, KC wrote: On 2/12/2014 11:23 AM, HanK wrote: On 2/12/2014 10:40 AM, KC wrote: On 2/12/2014 10:31 AM, KC wrote: On 2/12/2014 10:04 AM, Mr. Luddite wrote: On 2/12/2014 9:36 AM, KC wrote: On 2/12/2014 9:17 AM, Mr. Luddite wrote: On 2/12/2014 8:09 AM, Poco Loco wrote: On Tue, 11 Feb 2014 20:27:03 -0500, Earl__ wrote: Mr. Luddite wrote: On 2/9/2014 6:25 PM, Poco Loco wrote: On Sun, 9 Feb 2014 15:03:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 4:30:04 PM UTC-6, John H. wrote: On Sun, 9 Feb 2014 13:31:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 7:31:31 AM UTC-6, F.O.A.D. wrote: I'd love to have one of these... http://www.youtube.com/watch?v=U7mTwM7afQA how about something like this? http://thekneeslider.com/1937-front-...cle-prototype/ Looks like something Moto Guzzi made during the war. "Goose" probably tries something like that too, but this is French, and the French at that time were known to be great tinkerers, with results to match. Yeah, I should have said it looks like something Guzzi *could* have made during the war. Something like this: http://www.youtube.com/watch?v=4cOlS_ShXf4 Here's an idea for Scott: (warning - contains boating content) http://www.elrellano.com/videos_online/8146/barca-a-motor.html No steering unless that rowboat has a bow thruster. That boat is a high technology marvel incorporating 'eyeball sensormatic rotational assist'. Where you look is where you go. A sign on the bow says, "Don't look at women when operating this vessel." Sometimes the sign gets torn away. When I was a kid I had a 12' aluminum boat with a little 3hp outboard. I'd tighten the tension on the steering so the motor wouldn't move, sit in the middle seat and steer just by leaning towards one side or the other. Worked fine in large ponds. Somebody said "like a motorcycle"... But if you simply lean a motorcycle and don't turn the wheel, it will still go straight... Just sayin'. No, you have to tip the boat. Speaking of motorcycles, ever try this? Ride going straight ahead and push your *left* handlebar forward gently and see which way you turn. Then try with the *right* handlebar. Yeah, that's how she takes every turn... Reverse steer. Add in breaking loose the rear tire and you are starting to have some fun however, if you do though, you are losing time going sideways instead of forward ![]() Just reread that... I should say she counter steers when the suspension or body position is off... But it's not the fastest way around the track... What is the fastest way around the track? Ok, the fastest way involves being efficient in the corners. If you are countersteering n a corner, you are standing the bike too high, and the drive wheel is not taking the shortest distance around the corner. In racing terms, you blew out the birm.. It's not efficient to have that back tire way out there cause then it takes time to bring it back... How can you be efficient in the corners? Balance.. Keep both tires in as close to the same radius as the other. You want the front tire pointing as close to the direction of thrust from the rear tire as possible. If you are "countersteering" you are losing forward thrust and burning off forward thrust... Geeze. I'll never enjoy a warm summer evening cruise down to the Cape again. :-) Sure you will. Like you said you are not racing... I said before I get the whole thing about getting into a corner and even counter steering. The looser you are, the more you do it too.... but it's still not the most efficient way to make a corner... You guys are all supposed to be sailors.. Draw the thing out and draw out the thrust and resistance lines... you will see what I am talking about... Anyway, I have a good drawing that I can put up later. For now I will say there are a couple other things we do to make the bike corner better. One in particular is to gently pull the front brake in and dip the front end which shortens the turning radius and increases the angle of the front suspension more upright to turn.. (more like a tricycle)... Even dipping the front end a couple inches reduces the bike length by as much as an inch and can change the rake of the front end 8-10 degrees... But again, you are not racing. If I was you I would be countersteering all the way to the beach. I know how good it feels and I wouldn't be "racing" on the street anyway ![]() Phew. I was getting worried there. It's sorta hard to steer a 850lb Harley with the back tire. Even if I could, it would probably be the last turn I ever made. Yup... Imagine so. I had times where I slid my Honda into a countersteer slide when I was younger. Never intentionally though ![]() weight of your bike too... Hell, no wonder I did not win every race with my Vette. I was drifting corners at times. The old Laguna Course, turn 2 was always able to go faster than you figured as the apex of the corner started up hill. Loading the suspension and increasing traction. Turn 3 was a very highspeed turn and you drifted it at about 130 mph. Here's my point... You drifted that corner at 130, scrubbing forward speed off in the drift... How about I come behind you in a formula racer that can take the corner without countersteering and breaking traction.. how fast do you think that car might make that corner with all the hp pushing it forward?? Different vehicle. it would be drifting at a much higher speed. Coefficient of friction for an F1 car is probably 1.75 to 2 all the down force adding to the apparent weight of the car, without a Mass increase, adding to the traction. Is a major reason F1 racing is not as exciting as a lot of other racing. No passing really. If another car gets close enough to a good running car, the airflow is corrupted and the car loses down force. Not being able to make the turn. And the Horsepower is close enough that you can not pass on a straightaway. How fast could the same car make the turn without drifting is the real question. Slower than the drifting car normally. And horsepower is not the answer. Only so much of the horsepower is usable at any time. A long straightaway is the only place where the excess HP can actually be used. When you hit the red line on a Straightaway, you are maxing out HP usefulness. Why do you always see Sprint Cars on a dirt track on straight to the track? Because they are drifting and putting the drive force at the best angle to drive the the fastest around the corner. If your bike had enough HP spin the wheels anytime, you would have tires with a very aggressive grip trying to drive that bike at the best angle to the turn to go faster around the turn. Not just trying the perfect non slip line through the turn. |
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On 2/12/14, 2:09 PM, Poco Loco wrote:
On Wed, 12 Feb 2014 16:21:26 -0500, KC wrote: On 2/12/2014 3:52 PM, Poco Loco wrote: On Wed, 12 Feb 2014 15:15:41 -0500, KC wrote: On 2/12/2014 12:35 PM, Poco Loco wrote: On Wed, 12 Feb 2014 11:44:07 -0500, KC wrote: On 2/12/2014 11:20 AM, Poco Loco wrote: On Wed, 12 Feb 2014 10:33:01 -0500, KC wrote: On 2/12/2014 10:06 AM, Mr. Luddite wrote: On 2/12/2014 9:42 AM, Poco Loco wrote: On Wed, 12 Feb 2014 09:06:41 -0500, BAR wrote: In article , __ says... Mr. Luddite wrote: On 2/9/2014 6:25 PM, Poco Loco wrote: On Sun, 9 Feb 2014 15:03:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 4:30:04 PM UTC-6, John H. wrote: On Sun, 9 Feb 2014 13:31:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 7:31:31 AM UTC-6, F.O.A.D. wrote: I'd love to have one of these... http://www.youtube.com/watch?v=U7mTwM7afQA how about something like this? http://thekneeslider.com/1937-front-...cle-prototype/ Looks like something Moto Guzzi made during the war. "Goose" probably tries something like that too, but this is French, and the French at that time were known to be great tinkerers, with results to match. Yeah, I should have said it looks like something Guzzi *could* have made during the war. Something like this: http://www.youtube.com/watch?v=4cOlS_ShXf4 Here's an idea for Scott: (warning - contains boating content) http://www.elrellano.com/videos_online/8146/barca-a-motor.html No steering unless that rowboat has a bow thruster. Just like a motor cycle, you just lean into the turn to make it go that way. No, leaning doesn't make it turn. Leaning enables the motorcycle to be kept more vertical when turning. Pushing on the handlebar makes you turn. Push left, go left. Push right, go right. Countersteering. Heh. I just mentioned to Scott about that. Those who don't ride will think it's weird. They think it should turn like a car. Yes, counter steering but again, it's not the fastest way around the corner ![]() It's the only way around the corner, at speed, on a motorcycle. I am beating myself up and I can't think of any place on the track where counter steering is faster... https://www.facebook.com/photo.php?fbid=10202016412913497&set=a.10202016402 113227.1073741828.1281248494&type=3&theater Here is Jess setting up for a corner... notice she is turning left, and her bars are slightly left.. If she let her back tire slide out more (blowing the corner) the bike would have to stand back up and the back tire come back in line to get out of the corner... don't know if that makes any sense. I have a video I could find later of two riders me and Jess study. One came though the corner right (her mentor) and the guy behind counter steered through and lost two seconds in the corner... Letting the back tire 'slide out more' is not a method of riding for anyone but dirt bikers. When she initiated the turn to the left, she did it by pushing on the left bar or pulling on the right bar. Once the bike started leaning (and turning) she can slide all she wants. I think what she is doing in the picture is coming out of a turn. So she's pushing on the right bar to straighten the bike up (or pulling on the left bar). Looking at the tracks in the dirt also shows that she's through the turn. That picture is in the first 30 feet of the turn.. and no. She doesn't have to push the left down to initiate the turn. Some turns she comes into airborne and she already has the bars turned in the direction of the turn... I see completely what you guys are talking about. I have had a mc licence since '76 and always thought that way... Until I started training Jess. She comes into a corner and throws her weight over the bike.. but pushes both bars down... the outside bar further... never the inside bar, never let that rear tire get outside of the radius of the front tire...... Just the way it is. ![]() inside bar, the rear tire kicks outside the radius of the inside tire. now you have thrust pushing askew from the direction of the bike... we calle it "wash out" or "blowing the berm".. draw it out, put arrows for thrust.. You will see... Uh-huh. I just hope Jess, while on pavement going at speed, doesn't ever push left to go right. Something will get broke. OK, let's go from there.. When you are countersteering on the street, by design the thrust of the rear tire and front tire are not in sync with the direction of the turn.. So which tire do you slide? When I am on the street, I do everything in my power *not* to slide! When I still had my bike, I slid both tires. Recovered before the incidence went into disaster. Problem with need for speed and backroads. |
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On Wed, 12 Feb 2014 17:27:26 -0500, "Mr. Luddite" wrote:
On 2/12/2014 5:16 PM, Poco Loco wrote: On Wed, 12 Feb 2014 13:57:17 -0800, Bill McKee wrote: On 2/12/14, 1:46 PM, KC wrote: On 2/12/2014 4:37 PM, Mr. Luddite wrote: On 2/12/2014 4:10 PM, KC wrote: On 2/12/2014 3:36 PM, Mr. Luddite wrote: On 2/12/2014 3:05 PM, KC wrote: On 2/12/2014 2:47 PM, Poco Loco wrote: On Wed, 12 Feb 2014 13:59:51 -0500, HanK wrote: On 2/12/2014 11:37 AM, KC wrote: On 2/12/2014 11:23 AM, HanK wrote: On 2/12/2014 10:40 AM, KC wrote: On 2/12/2014 10:31 AM, KC wrote: On 2/12/2014 10:04 AM, Mr. Luddite wrote: On 2/12/2014 9:36 AM, KC wrote: On 2/12/2014 9:17 AM, Mr. Luddite wrote: On 2/12/2014 8:09 AM, Poco Loco wrote: On Tue, 11 Feb 2014 20:27:03 -0500, Earl__ wrote: Mr. Luddite wrote: On 2/9/2014 6:25 PM, Poco Loco wrote: On Sun, 9 Feb 2014 15:03:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 4:30:04 PM UTC-6, John H. wrote: On Sun, 9 Feb 2014 13:31:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 7:31:31 AM UTC-6, F.O.A.D. wrote: I'd love to have one of these... http://www.youtube.com/watch?v=U7mTwM7afQA how about something like this? http://thekneeslider.com/1937-front-...cle-prototype/ Looks like something Moto Guzzi made during the war. "Goose" probably tries something like that too, but this is French, and the French at that time were known to be great tinkerers, with results to match. Yeah, I should have said it looks like something Guzzi *could* have made during the war. Something like this: http://www.youtube.com/watch?v=4cOlS_ShXf4 Here's an idea for Scott: (warning - contains boating content) http://www.elrellano.com/videos_online/8146/barca-a-motor.html No steering unless that rowboat has a bow thruster. That boat is a high technology marvel incorporating 'eyeball sensormatic rotational assist'. Where you look is where you go. A sign on the bow says, "Don't look at women when operating this vessel." Sometimes the sign gets torn away. When I was a kid I had a 12' aluminum boat with a little 3hp outboard. I'd tighten the tension on the steering so the motor wouldn't move, sit in the middle seat and steer just by leaning towards one side or the other. Worked fine in large ponds. Somebody said "like a motorcycle"... But if you simply lean a motorcycle and don't turn the wheel, it will still go straight... Just sayin'. No, you have to tip the boat. Speaking of motorcycles, ever try this? Ride going straight ahead and push your *left* handlebar forward gently and see which way you turn. Then try with the *right* handlebar. Yeah, that's how she takes every turn... Reverse steer. Add in breaking loose the rear tire and you are starting to have some fun however, if you do though, you are losing time going sideways instead of forward ![]() Just reread that... I should say she counter steers when the suspension or body position is off... But it's not the fastest way around the track... What is the fastest way around the track? Ok, the fastest way involves being efficient in the corners. If you are countersteering n a corner, you are standing the bike too high, and the drive wheel is not taking the shortest distance around the corner. In racing terms, you blew out the birm.. It's not efficient to have that back tire way out there cause then it takes time to bring it back... How can you be efficient in the corners? Balance.. Keep both tires in as close to the same radius as the other. You want the front tire pointing as close to the direction of thrust from the rear tire as possible. If you are "countersteering" you are losing forward thrust and burning off forward thrust... Geeze. I'll never enjoy a warm summer evening cruise down to the Cape again. :-) Sure you will. Like you said you are not racing... I said before I get the whole thing about getting into a corner and even counter steering. The looser you are, the more you do it too.... but it's still not the most efficient way to make a corner... You guys are all supposed to be sailors.. Draw the thing out and draw out the thrust and resistance lines... you will see what I am talking about... Anyway, I have a good drawing that I can put up later. For now I will say there are a couple other things we do to make the bike corner better. One in particular is to gently pull the front brake in and dip the front end which shortens the turning radius and increases the angle of the front suspension more upright to turn.. (more like a tricycle)... Even dipping the front end a couple inches reduces the bike length by as much as an inch and can change the rake of the front end 8-10 degrees... But again, you are not racing. If I was you I would be countersteering all the way to the beach. I know how good it feels and I wouldn't be "racing" on the street anyway ![]() Phew. I was getting worried there. It's sorta hard to steer a 850lb Harley with the back tire. Even if I could, it would probably be the last turn I ever made. Yup... Imagine so. I had times where I slid my Honda into a countersteer slide when I was younger. Never intentionally though ![]() weight of your bike too... Hell, no wonder I did not win every race with my Vette. I was drifting corners at times. The old Laguna Course, turn 2 was always able to go faster than you figured as the apex of the corner started up hill. Loading the suspension and increasing traction. Turn 3 was a very highspeed turn and you drifted it at about 130 mph. This countersteering applies only to two wheel, single track vehicles! This discussion is heading back to the debate we had a while back about traction and what can take a corner faster ... a four wheeled car or a motorcycle. The "rolling cone" analogy Bill brought up applies to four wheeled vehicles where the outside wheels have to turn faster than the inside wheels in a turn. Really doesn't apply to a two wheeled motorcycle. The other thing is that Scott's style and techniques used in moto-cross racing has little to do with riding a street bike down a winding country road. Amen, to both. My brother, Jim, a former motorcycle cop, will tell you that on city streets the car will win - especially if someone has their sprinkler spraying the road!! He lost a Yamaha police bike that way. But, he said the car was gaining anyway. The radio had alerted enough cops to catch the guy though. |
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On Wed, 12 Feb 2014 17:40:16 -0500, KC wrote:
On 2/12/2014 5:17 PM, Poco Loco wrote: On Wed, 12 Feb 2014 16:14:00 -0500, KC wrote: On 2/12/2014 3:49 PM, Poco Loco wrote: On Wed, 12 Feb 2014 15:05:39 -0500, KC wrote: On 2/12/2014 2:47 PM, Poco Loco wrote: On Wed, 12 Feb 2014 13:59:51 -0500, HanK wrote: On 2/12/2014 11:37 AM, KC wrote: On 2/12/2014 11:23 AM, HanK wrote: On 2/12/2014 10:40 AM, KC wrote: On 2/12/2014 10:31 AM, KC wrote: On 2/12/2014 10:04 AM, Mr. Luddite wrote: On 2/12/2014 9:36 AM, KC wrote: On 2/12/2014 9:17 AM, Mr. Luddite wrote: On 2/12/2014 8:09 AM, Poco Loco wrote: On Tue, 11 Feb 2014 20:27:03 -0500, Earl__ wrote: Mr. Luddite wrote: On 2/9/2014 6:25 PM, Poco Loco wrote: On Sun, 9 Feb 2014 15:03:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 4:30:04 PM UTC-6, John H. wrote: On Sun, 9 Feb 2014 13:31:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 7:31:31 AM UTC-6, F.O.A.D. wrote: I'd love to have one of these... http://www.youtube.com/watch?v=U7mTwM7afQA how about something like this? http://thekneeslider.com/1937-front-...cle-prototype/ Looks like something Moto Guzzi made during the war. "Goose" probably tries something like that too, but this is French, and the French at that time were known to be great tinkerers, with results to match. Yeah, I should have said it looks like something Guzzi *could* have made during the war. Something like this: http://www.youtube.com/watch?v=4cOlS_ShXf4 Here's an idea for Scott: (warning - contains boating content) http://www.elrellano.com/videos_online/8146/barca-a-motor.html No steering unless that rowboat has a bow thruster. That boat is a high technology marvel incorporating 'eyeball sensormatic rotational assist'. Where you look is where you go. A sign on the bow says, "Don't look at women when operating this vessel." Sometimes the sign gets torn away. When I was a kid I had a 12' aluminum boat with a little 3hp outboard. I'd tighten the tension on the steering so the motor wouldn't move, sit in the middle seat and steer just by leaning towards one side or the other. Worked fine in large ponds. Somebody said "like a motorcycle"... But if you simply lean a motorcycle and don't turn the wheel, it will still go straight... Just sayin'. No, you have to tip the boat. Speaking of motorcycles, ever try this? Ride going straight ahead and push your *left* handlebar forward gently and see which way you turn. Then try with the *right* handlebar. Yeah, that's how she takes every turn... Reverse steer. Add in breaking loose the rear tire and you are starting to have some fun however, if you do though, you are losing time going sideways instead of forward ![]() Just reread that... I should say she counter steers when the suspension or body position is off... But it's not the fastest way around the track... What is the fastest way around the track? Ok, the fastest way involves being efficient in the corners. If you are countersteering n a corner, you are standing the bike too high, and the drive wheel is not taking the shortest distance around the corner. In racing terms, you blew out the birm.. It's not efficient to have that back tire way out there cause then it takes time to bring it back... How can you be efficient in the corners? Balance.. Keep both tires in as close to the same radius as the other. You want the front tire pointing as close to the direction of thrust from the rear tire as possible. If you are "countersteering" you are losing forward thrust and burning off forward thrust... Don't countersteer. Try turning the handlebars to the right next time you want to turn right. Do it at about 50 mph. Make sure your insurance is paid up. Can I start to lean first? If so, no problem.. Again, we do not lead with the front end of the bike... we steer with the rear end. The most efficient use of the power is for the front and rear wheel to be lined up, and the rear wheel tracking forward, not sideways... period... draw it out, you understand how to sail, you can get this. Again, countersteering is a common and useful tool, just not for us... Like I say. Get on the street, about 30 mph (so no one dies) and push the right handlebar to make a left turn. Let me know how it works out. How would it work out. I lean left, and push the right bar... no problem Let me know. Make sure you're clear to the right! |
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On Wed, 12 Feb 2014 17:41:25 -0500, KC wrote:
On 2/12/2014 5:14 PM, Poco Loco wrote: On Wed, 12 Feb 2014 16:21:26 -0500, KC wrote: On 2/12/2014 3:52 PM, Poco Loco wrote: On Wed, 12 Feb 2014 15:15:41 -0500, KC wrote: On 2/12/2014 12:35 PM, Poco Loco wrote: On Wed, 12 Feb 2014 11:44:07 -0500, KC wrote: On 2/12/2014 11:20 AM, Poco Loco wrote: On Wed, 12 Feb 2014 10:33:01 -0500, KC wrote: On 2/12/2014 10:06 AM, Mr. Luddite wrote: On 2/12/2014 9:42 AM, Poco Loco wrote: On Wed, 12 Feb 2014 09:06:41 -0500, BAR wrote: In article , __ says... Mr. Luddite wrote: On 2/9/2014 6:25 PM, Poco Loco wrote: On Sun, 9 Feb 2014 15:03:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 4:30:04 PM UTC-6, John H. wrote: On Sun, 9 Feb 2014 13:31:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 7:31:31 AM UTC-6, F.O.A.D. wrote: I'd love to have one of these... http://www.youtube.com/watch?v=U7mTwM7afQA how about something like this? http://thekneeslider.com/1937-front-...cle-prototype/ Looks like something Moto Guzzi made during the war. "Goose" probably tries something like that too, but this is French, and the French at that time were known to be great tinkerers, with results to match. Yeah, I should have said it looks like something Guzzi *could* have made during the war. Something like this: http://www.youtube.com/watch?v=4cOlS_ShXf4 Here's an idea for Scott: (warning - contains boating content) http://www.elrellano.com/videos_online/8146/barca-a-motor.html No steering unless that rowboat has a bow thruster. Just like a motor cycle, you just lean into the turn to make it go that way. No, leaning doesn't make it turn. Leaning enables the motorcycle to be kept more vertical when turning. Pushing on the handlebar makes you turn. Push left, go left. Push right, go right. Countersteering. Heh. I just mentioned to Scott about that. Those who don't ride will think it's weird. They think it should turn like a car. Yes, counter steering but again, it's not the fastest way around the corner ![]() It's the only way around the corner, at speed, on a motorcycle. I am beating myself up and I can't think of any place on the track where counter steering is faster... https://www.facebook.com/photo.php?fbid=10202016412913497&set=a.10202016402 113227.1073741828.1281248494&type=3&theater Here is Jess setting up for a corner... notice she is turning left, and her bars are slightly left.. If she let her back tire slide out more (blowing the corner) the bike would have to stand back up and the back tire come back in line to get out of the corner... don't know if that makes any sense. I have a video I could find later of two riders me and Jess study. One came though the corner right (her mentor) and the guy behind counter steered through and lost two seconds in the corner... Letting the back tire 'slide out more' is not a method of riding for anyone but dirt bikers. When she initiated the turn to the left, she did it by pushing on the left bar or pulling on the right bar. Once the bike started leaning (and turning) she can slide all she wants. I think what she is doing in the picture is coming out of a turn. So she's pushing on the right bar to straighten the bike up (or pulling on the left bar). Looking at the tracks in the dirt also shows that she's through the turn. That picture is in the first 30 feet of the turn.. and no. She doesn't have to push the left down to initiate the turn. Some turns she comes into airborne and she already has the bars turned in the direction of the turn... I see completely what you guys are talking about. I have had a mc licence since '76 and always thought that way... Until I started training Jess. She comes into a corner and throws her weight over the bike.. but pushes both bars down... the outside bar further... never the inside bar, never let that rear tire get outside of the radius of the front tire...... Just the way it is. ![]() inside bar, the rear tire kicks outside the radius of the inside tire. now you have thrust pushing askew from the direction of the bike... we calle it "wash out" or "blowing the berm".. draw it out, put arrows for thrust.. You will see... Uh-huh. I just hope Jess, while on pavement going at speed, doesn't ever push left to go right. Something will get broke. OK, let's go from there.. When you are countersteering on the street, by design the thrust of the rear tire and front tire are not in sync with the direction of the turn.. So which tire do you slide? Just so you don't think I'm lying to you: http://en.wikipedia.org/wiki/Countersteering Countersteering is the technique used by single-track vehicle operators, such as cyclists and motorcyclists, to initiate a turn toward a given direction by momentarily steering counter to the desired direction ("steer left to turn right"). A more accurate term is deliberate countersteering when employed by a rider, though it is often shortened to just countersteering. To negotiate a turn successfully, the combined center of mass of the rider and the single-track vehicle must first be leaned in the direction of the turn, and steering briefly in the opposite direction causes that lean.[1] This technique does not apply to conventional multiple-tracked vehicles such as trikes or sidecar-equipped bicycles and motorcycles. How it works[edit] A single-track vehicle such as a bicycle or a motorcycle is an inverted pendulum—it will fall over unless balanced. The technique used by cyclists and motorcyclists to initiate turning in a given direction is to first apply a steering torque in the opposite direction. For example, if a turn to the left is desired, it is started by applying a torque on the handlebars to the right. This causes the front wheel to rotate about the steering axis to the right and the front tire will generate forces in the contact patch to the right. The machine as a whole steers to the right briefly, and because the forces in the contact patch are at ground level, this pulls the wheels "out from under" the bike to the right and causes it to lean to the left. Then the rider, or in most cases, the inherent stability of the bike provides the steering torque necessary to rotate the front wheel back to the left and in the direction of the desired turn. Finally, the bike begins a turn to the left.[11] It is often boiled down to "push left to go left". While this appears to be a complex sequence of motions, it is performed by every child who rides a bicycle. The entire sequence goes largely unnoticed by most riders, which is why some assert that they do not do it. It is often claimed that two-wheeled vehicles can be steered using only weight shifts. While this is true for small "trim" inputs to direction, complex maneuvers are not possible using weightshifting alone because even for a light machine there is insufficient control authority.[12] Although on a sufficiently light bike (especially a bicycle), the rider can initiate a lean and turn by shifting body weight,[6] there is no evidence that complex maneuvers can be performed by bodyweight alone.[9] It is also important to distinguish the steering torque necessary to initiate the lean required for a given turn from the sustained steering torque and steering angle necessary to maintain a constant radius and lean angle until it is time to exit the turn. The initial steer torque and angle are both opposite the desired turn direction. The sustained steer angle is in the same direction as the turn. The sustained steer torque required to maintain that steer angle is either with or opposite the turn direction depending on forward speed, bike geometry, and combined bike and rider mass distribution. Deliberate countersteering is necessary to adjust the angle of lean of a bike and works in the opposite sense to the handlebar input while conventional steering in the direction of the turn is used to negotiate the turn. Need to lean to turn[edit] A bike can negotiate a curve only when the combined center of mass of bike and rider leans toward the inside of the turn at an angle appropriate for the velocity and the radius of the turn: \theta =\arctan \left({\frac {v^{2}}{gr}}\right) where v is the forward speed, r is the radius of the turn and g is the acceleration of gravity.[6] Higher speeds and tighter turns require greater lean angles. If the mass is not first leaned into the turn, the inertia of the rider and bike will cause them to continue in a straight line as the tires track out from under them along the curve. The transition of riding in a straight line to negotiating a turn is a process of leaning the bike into the turn, and the most practical way to cause that lean (of the combined center of mass of bike and rider) is to move the support points in the opposite direction first.[13] The rider can shift his weight of course, but any force used to move one way laterally pushes the bike laterally the opposite direction with equal force. That makes the bike lean (and can affect the steering), but it does not change the combined center of mass of bike and rider. Lean by countersteering[edit] When riding a bicycle or a motorcycle, deliberate countersteering is a method of initiating a turn by a small, momentary turn of the front wheel, usually via the handlebars, in the opposite (counter) direction. This moves the pivot point (the wheels' contact patches) out from under the center of mass to establish the lean angle for a turn. While exploitable at all speeds, the need to deliberately countersteer becomes more noticeable as speed increases. Hence, to turn to the right, the rider first throws the bike off balance by momentarily pointing the front wheel slightly to the left. The center of mass of the bike plus rider will continue in a straight line, but the contact patches of the tires move to the left with respect to this straight line. Once lean is achieved[edit] As the desired angle is approached, the front wheel must usually be steered into the turn to maintain that angle or the bike will continue to lean with gravity, increasing in rate, until the side contacts the ground. This process often requires little or no physical effort, because the geometry of the steering system of most bikes is designed in such a way that the front wheel has a strong tendency to steer in the direction of a lean. The actual torque the rider must apply to the handlebars to maintain a steady-state turn is a complex function of bike geometry, mass distribution, rider position, tire properties, turn radius, and forward speed. At low speeds, the steering torque necessary from the rider is usually negative, that is opposite the direction of the turn, even when the steering angle is in the direction of the turn. At higher speeds, the direction of the necessary input torque often becomes positive, that is in the same direction as the turn.[14] Adjusting or exiting a turn[edit] Once in a turn, deliberate countersteering is again required to make changes to its shape. The only way to decrease the radius at the same speed is to increase the lean angle, and the most effective way to increase the lean angle, is again to momentarily steer opposite to the direction of the curve. To the untrained, this can be extremely counter-intuitive. To exit a turn, a deliberate countersteer by momentarily steering further in the direction of the turn will tilt the bike back upright. At low speeds[edit] At low speeds countersteering is equally necessary, but the countersteering is then so subtle that it is hidden by the continuous corrections that are made in balancing the bike, often falling below a just noticeable difference or threshold of perception of the rider. Countersteering at low speed may be further concealed by the ensuing much larger steering angle possible in the direction of the turn. Unthinking behavior[edit] Countersteering is indispensable for bike steering. Most people are not aware that they employ countersteering when riding their bike any more than they are aware of the physics of walking. They have learned to apply the required countersteering without thinking. As is well known in bicycle racing, the countersteering phenomenon becomes evident when there is an obstacle preventing the wheel from countersteering (e.g., when closely overlapping wheels or riding very close to a curb). In these situations, the way to initiate a turn with the handlebars away from the obstacle is to countersteer towards obstacle to avoid crashing into it.[13] Lack of understanding of this principle leads to accidents in novice bicycle races. Gyroscopic effects[edit] One effect of turning the front wheel is a roll moment caused by gyroscopic precession. The magnitude of this moment is proportional to the moment of inertia of the front wheel, its spin rate (forward motion), the rate that the rider turns the front wheel by applying a torque to the handlebars, and the cosine of the angle between the steering axis and the vertical.[14] For a sample motorcycle moving at 22 m/s (50 mph) that has a front wheel with a moment of inertia of 0.6 kgm2, turning the front wheel one degree in half a second generates a roll moment of 3.5 Nm. In comparison, the lateral force on the front tire as it tracks out from under the motorcycle reaches a maximum of 50 N. This, acting on the 0.6 m (2 ft) height of the center of mass, generates a roll moment of 30 Nm.[14] While the moment from gyroscopic forces is only 12% of this, it can play a significant part because it begins to act as soon as the rider applies the torque, instead of building up more slowly as the wheel out-tracks. This can be especially helpful in motorcycle racing.[14] No hands[edit] Oh, so it's something you do once in a while.. I get it.. So, I can push my right bar to turn left if I want to... got it... Yeah, when you want to turn. The rest of the time you don't do it. Hey, you're cool. Try turning right by pushing right. |
#89
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On Wed, 12 Feb 2014 15:02:44 -0800, Bill McKee wrote:
On 2/12/14, 2:09 PM, Poco Loco wrote: On Wed, 12 Feb 2014 16:21:26 -0500, KC wrote: On 2/12/2014 3:52 PM, Poco Loco wrote: On Wed, 12 Feb 2014 15:15:41 -0500, KC wrote: On 2/12/2014 12:35 PM, Poco Loco wrote: On Wed, 12 Feb 2014 11:44:07 -0500, KC wrote: On 2/12/2014 11:20 AM, Poco Loco wrote: On Wed, 12 Feb 2014 10:33:01 -0500, KC wrote: On 2/12/2014 10:06 AM, Mr. Luddite wrote: On 2/12/2014 9:42 AM, Poco Loco wrote: On Wed, 12 Feb 2014 09:06:41 -0500, BAR wrote: In article , __ says... Mr. Luddite wrote: On 2/9/2014 6:25 PM, Poco Loco wrote: On Sun, 9 Feb 2014 15:03:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 4:30:04 PM UTC-6, John H. wrote: On Sun, 9 Feb 2014 13:31:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 7:31:31 AM UTC-6, F.O.A.D. wrote: I'd love to have one of these... http://www.youtube.com/watch?v=U7mTwM7afQA how about something like this? http://thekneeslider.com/1937-front-...cle-prototype/ Looks like something Moto Guzzi made during the war. "Goose" probably tries something like that too, but this is French, and the French at that time were known to be great tinkerers, with results to match. Yeah, I should have said it looks like something Guzzi *could* have made during the war. Something like this: http://www.youtube.com/watch?v=4cOlS_ShXf4 Here's an idea for Scott: (warning - contains boating content) http://www.elrellano.com/videos_online/8146/barca-a-motor.html No steering unless that rowboat has a bow thruster. Just like a motor cycle, you just lean into the turn to make it go that way. No, leaning doesn't make it turn. Leaning enables the motorcycle to be kept more vertical when turning. Pushing on the handlebar makes you turn. Push left, go left. Push right, go right. Countersteering. Heh. I just mentioned to Scott about that. Those who don't ride will think it's weird. They think it should turn like a car. Yes, counter steering but again, it's not the fastest way around the corner ![]() It's the only way around the corner, at speed, on a motorcycle. I am beating myself up and I can't think of any place on the track where counter steering is faster... https://www.facebook.com/photo.php?fbid=10202016412913497&set=a.10202016402 113227.1073741828.1281248494&type=3&theater Here is Jess setting up for a corner... notice she is turning left, and her bars are slightly left.. If she let her back tire slide out more (blowing the corner) the bike would have to stand back up and the back tire come back in line to get out of the corner... don't know if that makes any sense. I have a video I could find later of two riders me and Jess study. One came though the corner right (her mentor) and the guy behind counter steered through and lost two seconds in the corner... Letting the back tire 'slide out more' is not a method of riding for anyone but dirt bikers. When she initiated the turn to the left, she did it by pushing on the left bar or pulling on the right bar. Once the bike started leaning (and turning) she can slide all she wants. I think what she is doing in the picture is coming out of a turn. So she's pushing on the right bar to straighten the bike up (or pulling on the left bar). Looking at the tracks in the dirt also shows that she's through the turn. That picture is in the first 30 feet of the turn.. and no. She doesn't have to push the left down to initiate the turn. Some turns she comes into airborne and she already has the bars turned in the direction of the turn... I see completely what you guys are talking about. I have had a mc licence since '76 and always thought that way... Until I started training Jess. She comes into a corner and throws her weight over the bike.. but pushes both bars down... the outside bar further... never the inside bar, never let that rear tire get outside of the radius of the front tire...... Just the way it is. ![]() inside bar, the rear tire kicks outside the radius of the inside tire. now you have thrust pushing askew from the direction of the bike... we calle it "wash out" or "blowing the berm".. draw it out, put arrows for thrust.. You will see... Uh-huh. I just hope Jess, while on pavement going at speed, doesn't ever push left to go right. Something will get broke. OK, let's go from there.. When you are countersteering on the street, by design the thrust of the rear tire and front tire are not in sync with the direction of the turn.. So which tire do you slide? When I am on the street, I do everything in my power *not* to slide! When I still had my bike, I slid both tires. Recovered before the incidence went into disaster. Problem with need for speed and backroads. I slid the front tire once. Scared the **** out of me (almost literally), but I let off the brake quick enough to not go down. Back tire slides aren't that bad if you let it bring you to a stop. It's when you get scared while sliding and let off the brake that you stand a good chance of 'high siding' and going down. |
#90
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Mr. Luddite wrote:
On 2/12/2014 9:36 AM, KC wrote: On 2/12/2014 9:17 AM, Mr. Luddite wrote: On 2/12/2014 8:09 AM, Poco Loco wrote: On Tue, 11 Feb 2014 20:27:03 -0500, Earl__ wrote: Mr. Luddite wrote: On 2/9/2014 6:25 PM, Poco Loco wrote: On Sun, 9 Feb 2014 15:03:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 4:30:04 PM UTC-6, John H. wrote: On Sun, 9 Feb 2014 13:31:40 -0800 (PST), Tim wrote: On Sunday, February 9, 2014 7:31:31 AM UTC-6, F.O.A.D. wrote: I'd love to have one of these... http://www.youtube.com/watch?v=U7mTwM7afQA how about something like this? http://thekneeslider.com/1937-front-...cle-prototype/ Looks like something Moto Guzzi made during the war. "Goose" probably tries something like that too, but this is French, and the French at that time were known to be great tinkerers, with results to match. Yeah, I should have said it looks like something Guzzi *could* have made during the war. Something like this: http://www.youtube.com/watch?v=4cOlS_ShXf4 Here's an idea for Scott: (warning - contains boating content) http://www.elrellano.com/videos_online/8146/barca-a-motor.html No steering unless that rowboat has a bow thruster. That boat is a high technology marvel incorporating 'eyeball sensormatic rotational assist'. Where you look is where you go. A sign on the bow says, "Don't look at women when operating this vessel." Sometimes the sign gets torn away. When I was a kid I had a 12' aluminum boat with a little 3hp outboard. I'd tighten the tension on the steering so the motor wouldn't move, sit in the middle seat and steer just by leaning towards one side or the other. Worked fine in large ponds. Somebody said "like a motorcycle"... But if you simply lean a motorcycle and don't turn the wheel, it will still go straight... Just sayin'. No, you have to tip the boat. Speaking of motorcycles, ever try this? Ride going straight ahead and push your *left* handlebar forward gently and see which way you turn. Then try with the *right* handlebar. That only works at higher speeds and I was taught how to ride that way. It was difficult to do at first since it didn't make sense. BTW - VERY gently - just a bit of pressure. |
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