| Author | Message | ||
     Danger_dave |
>>I need to turn, I turn, bike turns, WE turn. Thinking about it will F*ck me up.<< I'm even more egotistical - the bike is attached to ME. I go - it follows. | ||
| Ft_bstrd |
I'm even more egotistical - the bike is attached to ME. I go - it follows. Yeah, that happens when you're a big guy. Even big bikes are a suppository. | ||
| Rocketman |
Patrick, that is what I am saying. The tiller scenario is bang on too. And yes, the 916 is dam near impossible to steer using your inside bar. Of course, there is finite control there, just like any bike where just as Blake described, it's a constant adjustment between pushing and pulling on both sides of the bar. If you try to give the inside bar on a 916 greater inputs, you destabilise the bike almost instantly. Now about that 'Wall'. I'm thinking, maybe wrongly so, that the bike is not going uphill, just in a straight line. All be it with a very strong side wind. The mind boggles! Anyways ladies and gentlemen. The last time we got into this steering debate thing a year or three ago, I trawled the Internet like a man possessed. Well, I have done likewise these past 24 hours or so, and found these interesting studies. The first I found somewhat possible to follow that made sense, written by J Fagans from University of California, Berkley, appears to suggest I'm completely wrong. But the author does admit his studies are based on that of a bicycle, which he claims has the same characteristics for his experiments as that of a motorcycle. But, and I emphasise 'BUT', he has never ridden a motorcycle. Steering in Bicycles and Motorcycles Another very informative study I came across is that of the Motorcycle Dynamics Library in Modelica. This study relies upon model simulation and does require more brain calculating power than I'm ever likely to have, but after all was said and done I especially liked the concluding paragraph where the authors say, and I quote "moreover, we plan to extend the driver model so to insert the driver lean angle as an additional degree of freedom in the motorcycle model, in order to model the driver as active, capturing his real behavior and its effects on the overall vehicle dynamics". What? You mean this experiment is not entirely accurate after all? What's of further interest about Modelica's study is, as Fats suggested, they use a tiller to input steering for sake of their model simulation. Unfortunately they don't explain why, but it's pretty obvious if you think about it. A tiller eliminates the inputs necessary at both ends of a handlebar type lever, where such would make it rather complex on a simulation model of a motorcycle going around a race track. A tiller operates much simpler than a handlebar for purposes of steering a simulator model, and for that matter in replacing a human being as a pilot. For this reason I'm adamant that no amount of testing has ever proven the inside bar takes precedence when banked into a corner on a motorcycle. Enjoy the read. They are worth it if you don't find this stuff too boring. Here's Modelica's study. Motorcycle Dynamics Library in Modelica Rocket | ||
| Crusty |
Yeah, that happens when you're a big guy. Even big bikes are a suppository. In that case, a big guy should name his Ducati after the new Italian suppository: Innuendo. | ||
| Josh_ |
tiller=single bar=steering with one hand Makes it easier on the rider and the computer simulation ... | ||
| Danger_dave |
>>In that case, a big guy should name his Ducati<< PITA | ||
| Rocketman |
Tiller steering (one hand) is not comparable with hands either side of a handlebar. No simulation using a tiller can ever answer the question as to which hand takes precedence in a corner. Rocket | ||
| Ft_bstrd |
Tiller steering (one hand) is not comparable with hands either side of a handlebar. No simulation using a tiller can ever answer the question as to which hand takes precedence in a corner. But it does substantiate my position that the force applied by the handlebars is equal regardless of whether you push the bars or pull the bars and pushing on one is equal to pulling on the other. In reality, we ONLY push on bars. Exiting or reversing a turn will require pressure on the outside bar that would be very difficult to apply to the inside bar (because you would need to pull the bar). | ||
| Brumbear |
If you live in N.J. you better keep both hands on the bars with our roads you could be in for a long off season you start doing that crap | ||
| Rocketman |
But it does substantiate my position that the force applied by the handlebars is equal regardless of whether you push the bars or pull the bars and pushing on one is equal to pulling on the other. Again, I don't know if the physical effort, as measured by a spring balance for instance, is the same or not. It stands to reason it probably is, but it does not answer the question "does pushing the inside bar take precedence in a corner"? What you need to think about is how you are going to apply that effort. Whilst it might take the same amount of effort to operate either side of the handlebar, you can't do jack if you are not in the right place to apply that effort. This is why, for example, it is dam near impossible to push the inside bar with precedence over pulling the outside bar on my 916. It's just not physically possible to place your body in a position that allows you to do so. I suspect this is the case for a lot of motorcycles. Buells might well escape such notice as their bars are generally wider and more upright, and I'd assume this finding applies to different types of handlebar styles and riding positions. It should be noted though, I understand another thing is happening which harks back to what Blake said. If we image we are pulling the outside bar when leaning into a corner, that effort is constantly changing between a positive pull and a negative opposite force, which will result in the bar going away from your pulling hand. I suspect you will feel this force on your inside hand though whilst you are not actually pushing with your inside hand that is what it will feel like you are doing. In reality one could perhaps argue this is pushing, but all that is happening is your inside hand is acting as a steering stop which is feeling the counter steer effect or negative force of your outside hand, which is still pulling. So, I am still flying in the face of the so called experts. Be they authors of how to ride better or mad scientists using tillers to steer experimental motorcycles. I have no books to profit from, and I'm not selling my expertise to the motorcycle industry. I just do this for fun  Rocket | ||
| Blake |
One should avoid pushing or pulling on one's tiller while riding. | ||
| Sanchez |
> Again, I don't know if the physical effort, as measured by a spring balance for instance, is the same or not. It stands to reason it probably is, but it does not answer the question "does pushing the inside bar take precedence in a corner"? There are two questions here. 1) From a pure physics perspective, does it matter which end of the bar you apply force to? 2) From a human anatomy/body position perspective, do you have better leverage on one bar or the other. The answer to #1 is that it makes no difference. Pulling one is the same as pushing the other. The answer to #2 is that it does make a difference. Depending on how your weight is distributed and how your body is positioned, one will be easier than the other. Given the entirely different set of muscles required to push vs. pull, I'd go so far as to say that one will always be easier than the other. | ||
| Azxb9r |
The thing that has been lost in this debate is the reason that Parks wanted you to have all steering input with the inside hand. . . so the left hand is not fighting with the right hand for steering control. If it makes you feel more comfortable using the outside bar end, have at it. | ||
| Ikeman |
As I was reading through this whole thread I'm thinking the same thing that Azxb9r posted. I was waiting to get to the end of the thread to see if someone already posted it. I haven't read through the book in a while but that's the way I remember it, too - if you find your hands fighting for control, steer with the inside hand. | ||
| Rocketman |
Parks is talking rubbish then. The question is, which hand takes precedence, and that's the only question. If that requires proof, ride any motorcycle, be it leaned into a corner or upright and think about what your hands are doing. There is simply never a time when either pushing or pulling, no matter which hand or bar end, remains constant. Try to imagine what you are saying and put it into a time frame of milliseconds all joined together. Even if you steer one handed, which is probably a very good experiment to try with this thread in mind, you will find your one handed effort is a series of push pull actions. You might not think so at first, maybe because all you feel is your hand tightened and relaxing on the grip constantly. That's your grip feeling both positive and negative forces, ie. pushing and pulling. So the question remains, which action takes precedence in a corner? There are simply some motorcycles that don't hold up Parks findings. I own one of them. I wonder if he's even ridden one.  Rocket | ||
| Ft_bstrd |
Could it be your bike is a pig?  | ||
| Reepicheep |
To prove that you really countersteer to a non rider, I went around a smooth sweeper with an open palm pressing on the inside bar of my XB9SX, other hand in the air. No pulling involved. But bikes that are designed to remain "neutral" through a corner (which, btw, I hate riding) would probably need pushing and pulling to maintain a steady state sweep. I seem to recall the VStrom I rode feeling like this. | ||
| Ft_bstrd |
I've taken right handers with only my right hand on the throttle and the left hand pointing out gravel hazards to the following rider. | ||
| Aesquire |
That "Steering in Bicycles and Motorcycles" article has, in figure 1, exactly what I think is happening when a turn is initiated. The turn of the wheel out from under the center of gravity, causing a lean, followed quickly ( very quickly ) by a turn into the curve, to stop roll axis rotation & actually turn the bike as lean & steering at the same time make for the lateral forces that cause you to actually change directions. I have used abrupt counter steering to lean the bike back & forth so that my tires missed a dead critter or bad pothole, when traffic & other riders did not permit changing lanes or position in the lane. From my perspective, my head stayed more or less in line with my path ( so I could have looked straight down at pothole ) while the bike leaned back & forth and the tires made a "S" track around the obstacle. In these cases, I never settled into a constant turn, but used counter steering to weave and return to straight & normal. I have noted that I can use either hand to steer around mellow curves while the other is checking bags for slipping, or waving at passing bikes. As to which hand is dominant? I can see that the leverage on the inside bar means that rotation about the steering head is more side to side & less fore and aft than at the outside bar end. If you did not hang off at all, and had bars that "V" forward ( like some idiot Billy Lane construction See note below ) when turned the inside bar might have MORE leverage. Hanging off has got to complicate this. Thinking of the ergo's. If you are leaned hard over, hanging off, you have to be "hanging" your mass somehow with a combination of outside knee pressure and hands on the bar. I can see where it would be hard to pull the inside bar "up hill" to roll the bike out of the turn. I'll bet that Parks would be happy we are not insisting that toe pressure on the outside foot is what does all the mojo, but that we actually agree that turning the bars is the magic trick. ( unrelated Billy Lane note: I laughed my butt off while watching a biker build off where Lane made a double wall rear fender & routed the exhaust through it. "No One's ever done this" he said. "That's because it's stupid!" I yelled at the TV. Watching them throw the flaming seat in a muddy ditch & splash Perrier water on his smoking jeans made my day. ) (Message edited by aesquire on November 19, 2007) | ||
| Josh_ |
>would probably need pushing and pulling The experts will tell you that with a single track vehicle, the front wheel is constantly moving/oscillating, however minutely. Steering with one hand should be easier since you're only "listening" and responding to one input (one hand) instead of two. You only "initiate" a turn with a push on the inside bar. After the initiation of the turn, you may need to push or pull on the grip to maintain your line. Again, Lee Parks, Keith Code, Reg Pridmore and Chris Carr will tell you to use the hand tucked against your body as you should have better control over it. 'Course Carr (and I guess Rocket) will tell you the hand tucked against your body is the one outside the turn since you'll be up on top of the bike when flat-tracking. | ||
| Rocketman |
To prove that you really countersteer to a non rider, I went around a smooth sweeper with an open palm pressing on the inside bar of my XB9SX, other hand in the air. No pulling involved. I've taken right handers with only my right hand on the throttle and the left hand pointing out gravel hazards to the following rider. And in doing so you NEVER held the steering in one direction only. That's because it's not upto you. The motorcycle is constantly adjusting between positive and negative inputs as it moves forward, be it in a straight line or corner. The fact you THINK you are holding or pushing or whatever in one constant plane is why I suggested thinking in milliseconds. There are several parameters at work here that make it impossible to ride a motorcycle, for our example - in a corner, and have it turn a perfect arc. Road surface feedback / tyre movement, steering geometry, rider movement, wheel rotation, suspension travel, wind, and a few more I'm sure. Put it another way. If you are leaning into a corner and pushing on your inside bar as you describe with your other hand off the bars waving at the gathered crowd, what happens when you let go of the bar with your inside hand? You lose control instantly. That's because whilst you are pushing, the bar is also pushing back at you. Positive and negative right. You let go whilst leaning over and you will be very very lucky to get your hands back on the bar and regain control. Think oscillation. Think steering damper. Think where you have seen a good example of this phenomenon at work. TANK SLAPPER! Thus, cornering one handed supports my observations, though it does not answer which hand \ motion takes precedence in the corner. Hmm. Rocket | ||
| Rocketman |
Tell me Josh, what makes those guys anymore an 'expert' than you or I? They raced? They wrote a book? They're celebrities or something? Give me one good reason why their findings are more warranted than mine? The size of their trophy cabinets and their riding skills suckers you into believing them? The answer is in the palms of your own hands and for that you don't need a big trophy cabinet or your words published in books. Take my advice - FEEL THE FORCE. Rocket | ||
| Sanchez |
> Tell me Josh, what makes those guys anymore an 'expert' than you or I? They raced? Er, yes? > Take my advice - FEEL THE FORCE. I do feel the force. And it feels exactly like Lee Parks says it should.  | ||
| Rocketman |
And Lee Parks said go bury your head in the sand? Rocket | ||
| Sanchez |
If Lee Parks was a champion sand head burier, and I was trying to hone my sand head burying skills, then yes, I would likely follow his advice. | ||
| Igneroid |
When my Ukrainian grandad came to the new world, the first time he saw a motorcycle, he didnt think about none of this stuff, he said "Nobody pull-it, nobody push-it, and it go like hell!" | ||
| Blake |
I don't think keeping pressure on the inside bar during the middle of a turn is "counter-steering" since the front wheel is aimed toward the inside of the turn, not away, counter to it. Counter-steering takes place to get the bike leaned over where you do actually turn the front wheel counter to the direction of the curve. But once in the curve, the front wheel most definitely turns in to it. And to get the bike to stand up and track straight as we exit a curve, we turn the front wheel further into the turn, counter to the way we want to change direction of the bike. The need to push on the inside bar is a result of chassis geometry and front end setup. Some bikes exhibit that tendency, some don't. Reportedly the 1125R does not. Contact patch, contact patch, contact patch! Now I've really done it! ![: ]](http://www.badweatherbikers.com/buell/clipart/proud.gif) Synthetic oil, synthetic oil, synthetic oil! Doomsday cometh. | ||
| Strato9r |
Park's book was a huge help to get comfortable with the potential of my XB when I first bought it. What I noticed about the "Inside arm only" steering technique was that it did keep my arms from working against each other by using the inside arm to press forward on the bar to set the lean angle. The outside arm, while being relaxed, was able to "feel" the front end better; proving that the geometry of the bike did not need to be wrestled. The outside hand could then just hold the line that the inside hand had brought the machine to. This also puts your body in a more convenient position to "kiss the mirror", which is also a super easy, super effective trick. And, I'm not sure that taking either hand off of the bars on a public road corner is such a good idea. Those coyotes get pretty wrapped up in the spokes............ | ||
| Danger_dave |
Blake - In future such topics are to be referred to as 'The Scottish Threads' - K? | ||
| Danger_dave |
What about standing on the pegs and steering with no hands. Like it's a big skateboard. I like doing that. |
