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Thor

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Everything posted by Thor

  1. Ok, great, we're starting to get closer to some definition of your issue. Ok, the one thing that students (and i'll be honest, I never thought about this way either until about a year back, when I started to push traction issues further), don't realise is that a very large part of the bikes stability comes from the rotational forces of the wheels. The higher the speed, the more stability the bike has (which is also one of the reasons its harder to turn a bike the faster you go), as the gyroscopic forces of the bike get ever hgiher. As you've now started to think about this, you'll know that your going to in most situations starting to stand the bike up on the way out of a turn when you start to accelerate. At this point, what will happen with the bike if you start to reach traction limits is that it will start to slide or usually wobble a little. At this point, all that will happen to the bike is that the revs may rise a little, and the wheel will re-gain traction. As the rotational force of the wheel is still accelerating, it provides massive stability, so essentially the bike will want to stay upright and not just fall over mid turn. There is an important part here Steve if you feel this phenomen, and to be honest, you really have to be trying on a 600 (in the dry) to get to this as long as your accelerating at the right part of the turn when your starting to stand the bike up and your following proper throttle control, is that you mustn't chop the throttle (or you can get highsided). you must keep the throttle at least where it is, (we call this checked throttle), or just keep rolling on. Traction issues from the rear are very, very much controllable, (hence why you can see motogp riders spinning the bikes up out of turns), front end slides are much more difficult to handle and deal with. As long as you don't have huge lean angle coming out of a turn, your applying good throttle control, you'll always be able to deal with any rear end slide comfortably I assure you. Now, clearly, I don't expct you to just take my word for it, when you get to level 4 of the school, you'll be able to ride the slide bike, and you'll see how high traction limits are on modern tyres, and how managable these things are with correct throttle control. Hope this covers it of for you, and with some luck, we'll have some other students chime in at some point and share their experiences of rear traction issues and how they've managed them. Bullet So, you are saying that it is more difficult to turn a bike at speed due to gyroscopic forces. You should bear in mind that many, many people have proven that what you say is simply false. Measured, scientific, and with practical applications. That does not mean you are wrong in what you are feeling, but do you think you could come up with another explanation that would concur with the scientific data (get your google on)? I think there is, but I also don't believe that the science that gyroscopic force in negligable, at best, is necessarily applicable to the real world, i.e. teachable. I believe that you are denying a myriad of motorcycle components, including the rider, that have a significantly large effect and influence on a phenomenon you are blaming on "gyroscopic force." I feel that you have fallen into the trap of voodoo magic, like telling riders to, "put your head over the mirror" to corrrect body position. It may work as a quick fix tool, but in the long run, false science is a tool to correct the truly talented and handicap the rest of us humbled mortals. Rossi can have a chat with his bike before his race and do well. Myself, and most people, get an invitation by men in white coats for a cocktail party in a padded room when we do the same. Hi Thor, Thanks for your post, we like a good bit of informed, lively debate, helps spread the learning and knowledge for all. It's one of the primary aspects required of a coach when they join up that you have to aspire to have continued learning throughout your time, and as we're all pretty aware, there is a lot to riding a motorbike and always things to learn. Whilst this post was about traction, you're right that I breifly noted on difficulty in turning a motorbike, and yes, its based on experience and learning from keith and the school. If you have a copy of TW2, Keith talks in much depth about this in section 3, pages 54 onwards, so you're more than happy to read and question and offer up debate on this matter, certainly if there is information which furthers adds to everyone's learning. perhaps it might be helpful for all if you provide links to your points of contention so that there is no ambiguity in the topic matter? You're very correct about your statement about many factors involved in steering a motorbike, the design of motrocycle, the speed, the geometry of the bike, steering angles, trail, rake, tyre profile, leverage available via the bars, tyre and wheel weight all massvely affect how easy or difficult a bike is to turn, and I'm not in anyway trying to dismiss these factors at all, nor would I suggest that a riders ability to effectively steer should be underestimated also, however I do believe the principles and phsyics involved are well understand and have been demonstrated over many, many years. We don't believe in voodoo magic at CSS, if there were such a thing as Pixie dust, I think we'd have marketed that a long time back, and keith would be a very, very rich man! Bullet Yes, I was trying to frame the discussion in a way that would not devolve into a physics debate - Tony Foales can take us down that path and prove that we do not have the physics and math backgrounds to follow no matter how generous he is in taking that into consideration. That was a big mistake on my part. And I made a big mistake in using the terminology "voodoo magic". I don't use that term as a pejorative term. It is the shortcuts that I use to help me and my students move towards a way to effect the actions they want to happen. But the students have to develop their own "voodoo magic". What false idols and twisted logic I use to get myself to affect a proper action is not a reasonable way to explain it to students. It may not, most likely, make any sense to them. I felt that you were being lazy in communicating your point and wanted you to think about it from a teachable perspective. How can we transfer the most knowledge and understanding with the least amount of stress and confusion? I can turn on a dime when I am wrong, but I'll never stop throwing handfuls of quarters when I believe I am on the right path.
  2. Ok, great, we're starting to get closer to some definition of your issue. Ok, the one thing that students (and i'll be honest, I never thought about this way either until about a year back, when I started to push traction issues further), don't realise is that a very large part of the bikes stability comes from the rotational forces of the wheels. The higher the speed, the more stability the bike has (which is also one of the reasons its harder to turn a bike the faster you go), as the gyroscopic forces of the bike get ever hgiher. As you've now started to think about this, you'll know that your going to in most situations starting to stand the bike up on the way out of a turn when you start to accelerate. At this point, what will happen with the bike if you start to reach traction limits is that it will start to slide or usually wobble a little. At this point, all that will happen to the bike is that the revs may rise a little, and the wheel will re-gain traction. As the rotational force of the wheel is still accelerating, it provides massive stability, so essentially the bike will want to stay upright and not just fall over mid turn. There is an important part here Steve if you feel this phenomen, and to be honest, you really have to be trying on a 600 (in the dry) to get to this as long as your accelerating at the right part of the turn when your starting to stand the bike up and your following proper throttle control, is that you mustn't chop the throttle (or you can get highsided). you must keep the throttle at least where it is, (we call this checked throttle), or just keep rolling on. Traction issues from the rear are very, very much controllable, (hence why you can see motogp riders spinning the bikes up out of turns), front end slides are much more difficult to handle and deal with. As long as you don't have huge lean angle coming out of a turn, your applying good throttle control, you'll always be able to deal with any rear end slide comfortably I assure you. Now, clearly, I don't expct you to just take my word for it, when you get to level 4 of the school, you'll be able to ride the slide bike, and you'll see how high traction limits are on modern tyres, and how managable these things are with correct throttle control. Hope this covers it of for you, and with some luck, we'll have some other students chime in at some point and share their experiences of rear traction issues and how they've managed them. Bullet So, you are saying that it is more difficult to turn a bike at speed due to gyroscopic forces. You should bear in mind that many, many people have proven that what you say is simply false. Measured, scientific, and with practical applications. That does not mean you are wrong in what you are feeling, but do you think you could come up with another explanation that would concur with the scientific data (get your google on)? I think there is, but I also don't believe that the science that gyroscopic force in negligable, at best, is necessarily applicable to the real world, i.e. teachable. I believe that you are denying a myriad of motorcycle components, including the rider, that have a significantly large effect and influence on a phenomenon you are blaming on "gyroscopic force." I feel that you have fallen into the trap of voodoo magic, like telling riders to, "put your head over the mirror" to corrrect body position. It may work as a quick fix tool, but in the long run, false science is a tool to correct the truly talented and handicap the rest of us humbled mortals. Rossi can have a chat with his bike before his race and do well. Myself, and most people, get an invitation by men in white coats for a cocktail party in a padded room when we do the same.
  3. Your problem is it's a cloverleaf. A downhill cloverleaf (in any and every U.S. city I've been in) tightens up at the end to slow you down and straighten the merge lane. There are so many reasons why you shouldn't use a cloverleaf as a measure of your corning ability, that if it isn't obvious to you, there is no sense in me trying to explain it.
  4. I would say that vision skills are the Alpha and Omega of riding. If the vision skills aren't there, nothing else seems like it is going to come very easily. Also, vision errors can create problems when speed increases that weren't there before. I'm having a hard time thinking of many errors that aren't created by literally looking at the road in a way that works against you. After that, throttle control and quick turning. Then I would say efficiency - getting the nut that connects the seat to the handlebars from telling the bike to do things it doesn't want to do.
  5. I had a similar problem a few years back. It took me quite some time to figure it out. Basically, what was happening is that I was I was unconsciously introducing a steering input with my outside arm. When I used my outside arm as well as the inside arm for steering inputs I wouldn't get my body position in the correct place for the corner that worked for me. What ended up happening is that I turned and then adjusted which caused an additional bar input. If you need more grunt for your turning input, maybe concentrating on anchoring your outside foot and using that to stabilize you for a more aggressive input will get you the turning speed you want without the wobble. (And, no, I'm not talking about "peg weighting". I'm talking about "peg pushing.")
  6. Hmmm... So the 60/40 rule is 60% of the weight on the rear? Really?
  7. Try some different gloves. What you are describing can happen when your gloves are a little too tight and pull your fingers when you blip.
  8. I don't think the word "smooth" is very helpful to a lot of people. It is too ill defined. It's one of those, "You know it when you see it" terms. I've never been able to quickly get someone to stop their extraneous movements by asking them to be "smooth". They don't know what I mean. Now, if I explain that I want them to be efficient and limit there motions to only what is necessary, people seem to understand what that is more easily and will stop bobbing up and down before each corner and twisting and pulling and bouncing all over their bike. Fast, of course, is a relative term. Fast only has meaning in relation to something. With no reference, fast is a meaningless word. I can roll down the road at 15 MPH on a skateboard and it feels pretty damn "fast." "Fast" is just a shortcut from the true meaning, "Faster than..."
  9. I do that too! But the 2 stages of braking are ease it on then ease it off, in between the 2 stages is maximum braking which will differ for different situations, smoothness on the brake lever is key as if you experience a front wheel lock up you do not have to completely release the brake to regain control! Easing the brake out is just as important as easing it on and not grabbing a handfull of lever! On an interesting note a front wheel lock up can be controled by counter-counter steering if there is such a thing i.e. if you push right hand bar while the front wheel is locked the bike wil go left and vice versa but only while its locked, the rules return to normal as soon as the wheel begins to spin! So say if you brake deep into a right hander and lock the front, by putting a little pressure on the inside bar the bike will try to stand up only untill the wheel begins to spin again. I have overthought this technique and its messing with my head but I heard a pro racer talking about saving a crash with his knee and using this to his advantage! I think you got that a little confused. From riding dirt bikes, if the front starts sliding at high speeds a counter-steer will likely put you on your ass. You actually steer the bike. I have had to do this on pavement when I hit a false neutral going into a turn and the front started sliding. I didn't counter-steer, which would have just pushed the tire right out from under me - I steered the bike to gain traction until I slowed enough to regain traction. Then I could counter-steer again. It's a feel thing. If you haven't ridden dirt, you will most likely never learn what it is without crashing at high speeds repeatedly. You can't learn it on pavement without a whole lot of pain.
  10. Blipping has been a curiousity to me. I have always blipped for as long as I have been riding - 30 years. I don't remember learning it. I'm always amazed at how difficult it is for experienced riders to blip their throttle. Time and again I hear about how they find it so difficult. I've only found one successful way to teach blipping to people and to smooth out my blipping. I can't claim to have originated this technique, but I don't remember where I first heard of it. I have them get up to about 40 MPH in 4th or 5th gear. Then I have them try to hold their speed steady as the shift down the gears - 3rd, 2nd, 1st, and then back up. Up and down over and over keeping the same road speed the whole time. Then I have them up the MPH and do the same thing over and over. Once they get a feel for the relation of throttle to RPM and road speed, they have a less difficult time blipping. This is, of course, after addressing gross ergonomic issues.
  11. That msf-usa.org report was very interesting. Thanks for that, Thor. However, keep in mind that that report was based on "emergency braking". That is stopping the bike in the shortest distance possible with a full stop being the ultimate goal. Ultimately, like the report says, trying to modulate two independent braking systems is a very complex endeavour in any circumstance, even for an expert rider who is capable of standing the bike on its front wheel with the front brake. Add to that needing to blip the throttle for multiple downshifts in preparation for a quick turn maneuver and the level of complexity will overdraw the novice $10 bank account of attention pretty quick! IMO, in an educational situation, the question becomes, what is the best or most effective way to teach and/or learn to use the brakes? I have to agree with Keith Code's philosophy that proficiency with the front brake is paramount or foundational and best precedes any advanced skills training, ie. learning to use both brakes together to gain the last tenth of one percent of stopping distance which is not really critical in a normal riding situation and is far outweighed, IMO, by the ability to focus on more important things, like smooth simultaneous downshits. Personally, under normal circumstances, I find that closing the throttle to weight the front wheel is more than sufficient. I then utilize progressive braking force at the front lever and regularly lift the rear wheel under racing conditions. The only time I use the rear brake as suggested in the msf-usa report (outside of slippery conditions, ie. rain, oil or off-track grass, dirt, gravel, etc) is if the front wheel is still light after rolling off the throttle, ie. say when needing to brake while cresting a hill. And although the flywheel effect of the motor may ultimately increase stopping distance by .01 percent during an emergency stop, I NEVER pull in the clutch when braking under normal circumstances. racer For the track, it would be a good idea to look at the second link. The rear brake increases stability of the bike. If you don't have the brain power to use both brakes, fine. I don't when I'm going fast, most of the time. After 30 years of riding, and 7 on sportbikes, it's taken me 2 years to get a feel for the rear brake on my sportbike. It definitely decreases the "drama" of the bike when rapidly slowing. Do I use it all the time? No. It depends on how important it is to have the bike controlled. If I don't mind the bike getting a little loose and squirrely, I don't worry about it and use the clutch and down shifts to control the rear. If I need the bike to be as smooth and controlled as possible, I use the rear. Now how I do that is a whole different discussion.
  12. A couple things to look at: http://www.msf-usa.org/imsc/proceedings/a2...kingSystems.pdf http://www.dinamoto.it/DINAMOTO/on-line%20...braking_new.htm
  13. I'm a big fan of hydration. I've read a lot about it and there is much disagreement. I teach MSF BRCs every weekend all summer in MN. It gets up to 90 plus degrees F with very high humidity. I worked at a golfcourse as a kid and sat with a 20hp engine literally between my legs. It got amazingly hot and I was only one who could ride the maching all day. Everyone else would shut down and give up or suffer from heat related problems. When they found out that how I did it was to get to work a 1/2 hour early and hide 5 one gallon jugs of water in the woods, the club paid for fancy hidden water jugs for the crew. When I teach, I tell the students to bring 5 liters of water and plan on drinking one liter at every break. My hope is that they'll drink half a liter. The students also watch me drink and fill a 2 liter CamelBak throughout the day. If I see a student who refuses to drink water, I can tell you exactly which exercise on day 2 their mind and body will stop working correctly. If a student drinks alcohol the night before, I can tell them what will happen, how it will happen, and what they will be thinking at the time. Other coaches mock me for telling adults what to bring for water, but more of my students pass, fewer, if any, drop out, and I don't have to deal with the mental and physical meltdown that leads to crashes in the more advanced skills. I don't know exactly why it works, and I don't really care. I know it works and makes me more comfortable and helps my students perform better. When I only teach the range and can't advise students what to bring, I suffer for it because they don't bring water or they don't bring enough. On day 2 it is like someone beat them with a stupid stick. Complete "helmet fires" and lost comprehension. I also bring enough bananas for every student to have two. The problem is some people get an upset stomach from bananas, but the potassium seems to help (or maybe it is just having some food to eat.)
  14. And you don't have problems with turn 5 at Barber? That is the tightest corner on the track.
  15. I think it is wrong to think that they are actively doing this. I don't believe that they are. It just happens because their foot is off the peg after/while downshifting. I have had occasions where my foot was bouncing on the lever downshifting and the rear got real loose and moved with the camber of a turn. My foot didn't go back on the peg as I got the back end in line. I didn't think about it. I'm a putz. It just happened. These riders are world class and are all about feel and balance right at the edge. They "feel" what is right and go with it. If it happens to be that the foot is off the peg when they do this, that is what it is. It isn't a technique, or skill, it is feel and balance and control...well, at least for them. For me, it just happened because I made a number of mistakes and had to compensate. My foot being out in the air was the least of my problems!
  16. I had a similar problem a few years ago. I thought there was something wrong with the front end of my bike. I would get the feeling that the front was sliding at every turn in. I knew it wasn't, and it sounds similar to your "rebounding". The result of this was a slight delay in getting back on the throttle. Then the front actually did start pushing. I was basically out of control for way to long getting into a turn. I learned that I was sitting on the bike wrong. I found the solution was to not "try" to have the "right" postion on the bike, but to set my position based on the turn and use my upper body to adjust before turn in. (I mean, seriously, you can only shift your lower body over so far before you become unstable.) It took someone looking at me ride and asking me if I knew I was moving/sitting oddly on the bike. I basically followed him and mimiced what he did.
  17. I cannot believe that this thread is going on like this! This has got to be the most retarded bunch of mental masturbation I have ever read! If your bike is falling over mid turn, speed up!!!! I'm sorry, but the "keep it simple stupid" principle should have been applied early on here. Seriously, has anyone else ever had this problem?!! (Sorry I blew up.)
  18. You can watch the same thing with motogp. When they show the throttle and brake applications of the riders on the telecast you can see them all trailing the brakes into the turn. I suspect that you will hear that it is an advanced skill that only has a place in racing and not in all turns. Last year the rebound damping in my forks when to hell. I don't like trail braking on the streets because of the way it wears my tires and the fact that it leaves you in a bad place if you run into gravel. To keep the front end from coming up and pulling me wide mid turn with my wonky forks, I would drift into the turn enough to keep the forks loaded and then make a quick turn from there. The people I was riding with couldn't figure out what I was doing and didn't understand how I could appear to be doing a lazy turn in and then quickly get to the apex. This is really a lite version of trail braking. I've been a disciple of the Code method for many years, yet there are things that I don't quite understand. When I toss the bike in quickly, and off the brakes, there is always a split second where I'm really not in control. It is very brief and doesn't concern me much, but it doesn't feel right. I can also turn quickly enough to break the front tire loose. I suspect that is bad technique or bad road in some instances. Also, I can turn and open the throttle at the same time. If I am really moving and do this, the bike will pull wide mid turn. When you get to the top racers with the top tires and top traction, I suspect that the rules and the goals may be a little different. One of the cycle magazines had an article on Ben Spies and his tuner said that he is at maximum functional fork compression at mid turn. He is on the brakes hard at turn entry.
  19. im not qualified to answer your question, but how are you getting an early apex with a late turn in?? I have seen this, but I have never discussed it with anyone as I would like to see more riders do it to try to figure it out. There are two riders I ride with regularly who do this. They will go in deep into the corner and then they will turn so far that they hit the edge of the road (or their line) prior to the natural apex of the corner. How they deal with this is either roll off the throttle, delay roll on, or increase their lean angle. Both riders go through two front tires for every rear, which is the opposite of what I see with most people street riding. I don't know what they are thinking or feeling when they do this, but when I try to imitate it makes me uncomfortable. The only advantaged I can see is a sort of swoopy exit where you start standing the bike up sooner, but because of where you end up after the corrections you can't get it stood up, completely, as quickly. I can feel more "grind" to the tires doing this, but I don't like to ride so that I am creating a "grinding" feel to the tires. I ride on the street as if my traction could be taken away from me at any split second, which can happen. Ripping on my tires leaves too much to chance and pushing traction on unpredictable back roads doesn't work for me.
  20. Trailing the brake: OK, just going to put out one thing here, when the brake is being trailed, does the bike want to hold it's line or run wide? Will there be more or less effort to turn it? CF The difference in effort you are talking about is so incredibly small on even the most difficult to turn bikes, that I wonder why you find it necessary to use that as an excuse for not trail braking. There are much better reasons for and against trail braking - and they all speak to the specifics of a turn. I have been a disciple of the Code techniques for more years than I can count on both hands, but there are fundamental exceptions to the basic rules that become more and more prominent as the technology advances year after year. Yes, you need to learn the fundamentals, but when the fundamentals start becoming a subset of what works every day for every rider, you need to stop and look at the basic philosophy and the premises behind your assertions. I think you are starting to lose your grip at the school, and you need to be more detailed and explicit in the questions you ask. Personally, I am starting to wonder if the teaching techniques you are using have outlived their usefulness as they are being applied today. The technique and style has incredible merit, going all the way back to at least Socrates, but the technique is violently opposed to any sort of dogma (hence, Socrates never writing a single word...ever. Plato, his student, wrote what he said.) I feel like you are becoming extremely dogmatic and have been that way for too long. I fear you may now be too established to every get back to the roots of thinking that made the initial venture great. Please prove me wrong! I don't want this to be an insult to how incredible your school is, but I think you are losing touch and your thinking has become polluted.
  21. It doesn't sound like this is what is happening to you, but I have had the sensation of the front slipping at turn in (not just before.) In my case this was caused by improper body position causing me to put inputs to the bars that I didn't know I was putting. It was very frustrating because I couldn't figure out why it was happening. I checked the bike from top to bottom and worked with the suspension - still doing it. Finally, I started thinking about what I was doing at turn in and went out, going over the same set of turns over and over, until I figured out that I was creating the sensation with improper inputs. I changed my body position and all was well. Problem solved (for me)!
  22. If you miss a shift (hit a false neutral) pull up (upshift.) It will go into gear much more easily than it will if you try to shift down. It can make the difference between going through a corner in the wrong gear vs. going through a corner with no way to get power to the wheel.
  23. I'd start by dropping your forks at least 6mm. It sounds like you created an oversteer problem with your new triple clamps. I have no idea why you would do something to "quicken" the steering for an R1. It sounds like you tuned the rideability out of it, now you need to tune it back in. I'd check the compression damping on the forks. I like to be able to push it about 2/3rds of the way through the stroke when I am seated on the bike, holding the front brake, and pushing down.
  24. What is the proper way to deal with headshake? I hear a lot of theories, and I have my own learned reactions, but I don't really know what I should do. The one that really made me think happened while going down the front straight at Barber. I was in fifth pulling 10,000 RPMs when the front started wobbling. I was leaving the power band and could really power out of it. I could see the brake markers coming up. I was about to do something about it, when it calmed down and I could get on the brakes when I wanted to. The thing is, I realized I don't really know what I should do when I am in a situation where I can't just ride it out. (Telling me to get a steering damper is not an answer.)
  25. I definitely agree with that. As an MSF RiderCoach we teach the students to use their rear brake in a "quick stop." For myself, when practicing quick stops, I don't use the rear brake. I've tried to learn how to use it, but when a true panic stop happens - which is about once every three years or so - I always end up noticing the rear brake locked the last 20-60 feet. That is usually the point where I have the opportunity to release the brakes and steer to avoid the obstacle. If the rear is locked and starting to go sideways, I've given up the option of swerving until I can get the rear back in line. I know there have been studies done where the results show that using both brakes, even with experienced riders, gives the shortest stopping distance. I think those studies either show how poorly even "experienced riders" are at stopping, or they don't take into consideration that a locked rear brake and the 10 feet you save stopping from 60 MPH isn't worth the loss of vehicle control. (It was a Canadian study that was done in the last few years. I can't find it right now.)
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