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  1. 3 likes
    I have translated it - let me know if it is OK to read, or I can share a link to my document for those interested. Who leans that far? Where are the limits? And what are the differences between street bikes? We compare bikes around a skid pad: Supermoto, Naked Bike, Cruiser und Superbike. We have also discused with experts and tried qualifying tyres from WSBK to see how they differ from street legal sport tyres. Why do we lean? Without lean to counter the centrifugal forces, the bikes would simply fall over. Leaning against the forces the correct amount keeps the machine and rider in balance. For a given radius, the faster one rides, the more one must lean. Or for a given speed, the smaller the radius, the more one must lean. How far can we lean? Sport bikes are generally limited by grip, or friction. With good tyres on a good road we typically have a friction quotient of one µ. This means we can theoretically lean 45 degrees. If you lean further, or you try to slow down or accelerate, you will slide. However, we know it is possible to achieve greater angles of lean. How? Because very grippy tyres and a grainy road surface can interact like gears. That’s why in MotoP and WSBK we can now see bike lean angles as high as 62 degrees. With the rider hanging off we can even see combined lean angles beyond that. What is that- different lean values? Corner master Jorge Lorenzo show us the difference between bike lean and the third lean. Lean angle isn’t always lean angle Basically, we talk about three lean angles. The first one is the effective lean angle. This is a theoretical value and is calculated from the speed and the radius of the corner. This counts for every bike and every rider. But this theoretical value for effective lean angle is based upon infinitely narrow tyres. Now to reality. Imagine watching a vertical bike from behind. Pull a vertical line through the bike’s centre line, the tyre and to the ground. This is where the contact point is as well as the CoG. Now place the bike on its kickstand. Now we see that the contact point between tyre and road has moved to the side somewhat because the tyres are not infinitely narrow. The more we lean the bike, the further away we move the contact point away from the bike’s centre line. If we draw a line through the CoG and both the centre line as well as down to the contact patch, we create a triangle. The angle between them is the second lean. This is the added lean required to corner at the same speed as you would have been with infinitely narrow tyres. This also show that wider tyres require more lean narrower tyres. Lorenzo shows us the difference between the bike’s lean and the third lean. With his extreme hanging off the rider is leaned over far more than the bike. The combination of the two - bike and rider - gives the third angle of lean, the combined lean. Bei 62 degree bike lean we can get to an extreme combined value of 66 degrees. What can production bikes muster? We take 4 different bikes and try them on the skid pad sitting in line with the bike, pushing the bike down and hanging off. We then measure bike lean, calculate combined lean and measure cornering speed. What gives the greatest speed? Lean angle with the Husqvarna 701 The skid pad has a diameter of 55 metres. Upright lean is 47 degrees, speed 57 kph. In typical sumo-style, pushing the bike down while leaning out, we managed 57 degrees bike lean and a speed of 62 kph. The combined lean is 51 degrees. This is the biggest difference in the test (6 degrees), a result of a light bike, high CoG, high and wide bars, narrow seat, low set pegs. Final attempt is hanging off, and we get the exact same values of 62 kph and 51 degrees combined lean. The bike is only leaning 46 degrees. So the speed is the same, but pushing the bike down sumo-style bring some advantages; more bike control and easier to catch slides being the predominant. Ducati Diavel, Cruiser & Co. Unlike for sport bikes, cruisers are limited by dragging parts when it comes to possible lean angles. With 41 degrees, the pegs are in contact with the asphalt. This will be the same regardless of what style is used. This gives us a fantastic opportunity to compare cornering speeds between the various riding styles. Sitting up gives 50 kph, pushing down 47 kph and hanging off 53 kph. MotoGP bikes can actually accelerate harder when leaned over than in a straight line. While maximum acceleration on level ground is limited to about 1g, a MotoGP bike can accelerate at 1.2g when leaned over 45 degrees! For street bikes on public roads, 45 degrees means zeron grip left for acceleration. A modern street legal sport bike outfitted with racing tyre and circulating on a grippy race track can give up to 1g of acceleration when leaned over at 40 degrees. Cornering with the Honda Fireblade First we ride on the stock Bridgestone S20 “G” tyres. Hanging off gives 61 kph and 48 degrees of lean for the bike, combined 51 degrees. What difference does qualifying tyres make? WSBK Q-tyre, straight from the heaters, has tremendous grip and feedback. We do not give up until the Fireblade gets “floaty”, a sign we are nearing the limit. With the bike leaned over 53 degrees we reached 65 kph. Combined lean is 55 degrees with the rider hanging off. Why not faster? The asphalt was cold (less than 10C / 50F) and the asphalt not overly grippy. Add a slight negative camber and the limits were like that. But this was the same for all tyres. The problem for the Q-rubber was that they lost their heat rapidly, losing grip in the process. A Pirelli-technician explained that the racers don’t lean further on Qs, but they have more grip available for braking and acceleration. Enough to give about a second lower lap times. Two laps, though, and they are mostly gone. Cornering with the BMW S 1000 R Standard Pirelli Diablo Rosso Corsa allowed 59 km/h when hanging off, with 47 degree bike lean and 50 Grad combined lean was good, but better results were limited by grinding foot peg feelers and gear shift lever. Foto: www.factstudio.de Husqvarna Supermoto 701 Sitting straight made the rider feel uneasy, which limited lean and cornering speed. Foto: www.factstudio.de The Sumo-Stil made the rider feel at most comfortable. Sliding tyres and grinding parts set the limit. Foto: www.factstudio.de If the rider had been able to hang as well off as he was at pushing the bike down, he could have cornered faster. Foto: Archiv Tyre width and CoG Wider tyres demand more lean for any given corner speed. The same goes for lower CoG. The difference between the tall Husky 701 with relatively narrow tyres and the low Diavel with its ultra-wide tyres was 3 degrees when doing 50 kph around the skid pad; 38 for the 701 and 41 for the Diavel. Foto: 2snap Lateral acceleration and lean While 45 degrees of lean gives 1g, 60 degrees give 1.7g, which isn’t the same as going 1.7 times faster by any means. Foto: www.factstudio.de Ducati Diavel A good way to see what the different riding styles can bring. Foto: www.factstudio.de Looks weird, feels weird. Foto: www.factstudio.de Feels much better than pushing the bike down!Foto: Archiv Der Kammsche Kreis This shows how much grip is left to brake or accelerate or steer at various lean angles. If you are leaned over to use half the lateral acceleration, you have 85% grip left to other forces (green arrow). The red arrow indicate that you have only 10% grip left to do anything else than circulate. Grip through the gear effect. Mikrorauigkeit (red) [micro coarseness], with spikes between 0,001 and 0,1 Millimeter is especially useful in the wet, while Makrorauigkeit (green) [macro coarseness] between 0,1 und 10 Millimeter make the difference on dry roads. Foto: Archiv Contact patch with a 180/55 sport tyre with a racing profile at 48 degrees of lean. 38 square centimetres contact area. Typical contact patch is that of a credit card. Public roads are more slippery than tracks, particularly in the wet because the surface lack Microraugkeit. Cold rubber, especially with sport tyres, can cause the tyre to slide on top of the asphalt instead of forming around it. Hence sport rubber is worse than touring rubber below a certain tyre temperature. Karussell around Nürburgring is bumpy and can be taken with 58 degrees of lean. However, thanks to the sloping surface, the angle between the road and machine is just 33 degrees. Lean and speed The Fireblade on WSBK Q-tyres managed 55 degrees of lean and 65 kph. If we theoretically put Marquez on the same skidpad with a combined lean of 66 degrees, he would have circulated at 78 kph.
  2. 3 likes
    The logic in getting more weight on the front, as I understand it, is that more pressure/weight on the front tire will increase friction (friction increases with weight) and also flatten the tire out more, making the contact patch larger, which doesn't increase friction directly (friction is not dependent on area, just weight) but CAN help the tire because too much pressure in too small an area can (I think) overheat the rubber and reduce the coefficient of friction, which WOULD reduce the overall grip. (Note - this is me giving you my own understanding, this is not superbike-school endorsed info.) Getting more weight on the front also can tighten up your steering by compressing the forks - but you can also get a similar effect with hook steering or changing your geometry or suspension settings. So that all works well for turn ENTRY, however once have turned the bike and have reached your desired lean angle and are pointed in the direction you want to go, if you don't get on the gas you will just keep slowing down. The best scenario for traction once you DO roll on the gas is: 40/60 weight distribution. Thus, the throttle control rule, "Once the throttle is cracked on..." So, the way I look at it, is while you are still slowing down and getting the bike turned, the weight on the front is a good thing (to a point - obviously using too much trail braking while turning can exceed your front tire traction), and once you are back on the gas, 40/60 is the way to go for best stability (we are no longer making lean angle changes at that point) and traction. Does that make sense? Do you remember from level 1 exactly WHEN you are supposed to START rolling on the gas?
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    This is the way I understand throttle control rule number two in Chapter 6: Fine modulation of the throttle helps you read the forces that you feel more accurately. The advantage of that is that your entry speed will be more consistent and appropriate than if you grossly decelerate in a hurry (charging the curve), just to find out that your entry speed (at the end of that precipitate deceleration) is lower than it should be (because your senses were overwhelmed, you are erring on the safe side of entry speed). The error about the entry speed is more significant for any fast-entry turn, especially due to the aerodynamic drag explained by Hotfoot above.
  4. 2 likes
    Drag racers rebuild their engines after each run. You really think cost is preventing them from running a skinny tire if they could gain a tenth? No. I have corresponded with the author of the article you link and while he might understand physics, I'm not convinced he understands motorcycle dynamics in a practical sense. The truth lies somewhere between the two. I have yet to find the answer. But the closest reasoning I've read that the coefficient of friction rather than being a constant can vary with temperature. Large contact patch might resist temperature change hence resist changes in coefficient of friction. Additionally, coefficient of friction does not accurately describe a rolling and cornering tire that operate with some slip angle. The tire is not stationary but not sliding either. No, it is too simplistic to say contact patch doesn't matter. From a practical motorcycling sense, much of Code's teaching talks about contact patch and friction. Based on all that practical experience of thousands of riders, there is some truth to the statement. Just my opinion.
  5. 2 likes
    At Buttonwillow RT in CA, turn 1, clockwise, April, I attempted a quick flick at 25 mph. It was session 2, first lap, and i went down. The front tire lost traction. After that crash i recalled the T2 video where the question is posed to the class, "Do you quick flick the bike when you're tires are cold?". The resounding answer: NO! The morning temperature was about 50F. Street tires. No tire warmers. I cancelled my late November track say in Chuckwalla without regret. Some like it hot.
  6. 2 likes
    The short answer: you have to work up to it and feel it out. The longer answer: Testing the grippiness of your tire must be done gradually, the idea is to increase lean angle gradually so that if the tire begins to slide there is some warning and opportunity to save it. The most pro coaches I have talked to on this advise gradually adding a little more lean at a time (corner after corner, or possibly even in the same corner if it is a long one) to feel out the traction, as opposed to just whacking it over to maximum lean and hoping for the best - because if you go too far too fast you will not have enough time to "sample" the traction and see how it feels, and know when you are approaching the limit. Some tires will have a specific feel to them when they are cold: the Dunlop slicks, for example, have a tendency to make the bike want to stand up in the corner and that is a good indicator that they are very cold. The carcass is stiff and reluctant to flex so when you lean into the corner it resists and sort of pushes the bike back up. Some other tires just feel a bit "wandery" in the corner, like they are sort of weaving around slightly, instead of feeling planted. If you have ridden in rain or ridden dirt bikes in the mud, you can recognize the feel of little slides, and little slides like that are your warning that you are at about the limit of traction for the conditions and the tire needs to warm up more before you can lean over any farther. It is a great exercise, when opportunity presents (winter is coming!) to pay VERY close attention to how your tires feel when stone cold, to develop a sense for it with your own bike and your own tire brand/model. It is difficult to quantify how long tires will take to warm up because it depends on tire type, air temp, track temp, wind conditions, how hard you ride, etc., so the best solution I know of is to feel it out carefully.
  7. 2 likes
    It's clear to me that a big piece of the puzzle is the bike set up. Some street bikes need almost effort to steer other require a firm hand, and others yet need assertive gymnastics to make them go where you want. After a decade of pushing a small 400cc fourstroke, Suzuki Impulse around corners at stupid speeds, back in them1990s I had a chance to consider more pricey alternatives. So out for a test ride. Fist a BMW boxer 800cc. Well that was interesting, It really didn't like corners at all. Sure it could change direction, but once turned in it was stuck on line unless brutally steered. Then a Suzuki RF900F. This bike didn't so much love going around corners as ignore the fact that corners might be challenging. Having eliminated the boxer, the two very different Suzukis are worthy of discussion. The Impulse turned as smoothly as the rider permits. Full extreme hang off, body vértices bike turning with the front wheel towing the bike into corners after initial countersteer, or suberbike style half cheek locked in sharp countersteer. Or even wild, suspension hammering turf the bike into the corner and hang on style the Impulse with its marginal 1980s cheap street bike suspension would take it all in stride. And cornered fast just like a lightweight ought to. but then by comparison the RF900f a prices, younger well developed sports tourer made the impulse look like a wanton child. Cornering was smooth, effortless, and stupidly fast. Counter steering -why bother. Hang off - if you really really want to. Lean the bike - nah it's doing that all by itself. How the hell is thing turning - well the obvious answer is it's going where you are turning your head towards. That's it just turning ones head. The once 80kph corner requiring a bit of rider concentration and effort, was just glided through at 80mph with little more than a glance in the right direction. The seated balance was perfect - zero bar weight required loose hands was well effortless. The suspension was unnoticeable. Stitching sweepers, chicanes and multiapex corners simply required the infinitesimal weight transfer that occured when turning the head. Seating remained inline with the bike. And ok, habit had me point a knee out but experimentation showed me that that was more for comfort than necessity. But why the 80kph, and the 80mph comparison. I knew the gorge road very well, a cornering speed 80 kph was what I thought I read on the speedo out of the corner of my eye, and was only a little faster than my norm on the impulse. I was being cautious as the bike was on loan from the store! On the flat and straight I'd time to take a closer look, and spdiscovered the imported bike speedo was miles per hour. So in fact I'd just been smoothly trundling along at 1.5 times the speed I'd thought I was doing on one of the most challenging roads in the city. Technology is a wonderful thing and perhaps explains much of that, but an improvement in corner speed of 35% with zero effort, or practice simply by changing bikes is I think extraordinary. More extraordinary is the minor detail that it's clear that it's not how the rider rides, but how s/he rides a particular bike. Perhaps the impulse could have been riden that extra 35% faster, but I can say for certain not by me! I say that with confidence as I've clocked up about half a million miles on impulses, and riden them to the limit, even occasionally well beyond into stupidly terrifying, brake, suspension and tyre failure territory, for much of that. The RF900F was just a better balanced, way more refined package that enabled the rider. The rf900 was effortless compared to the beasts of the early 1980s like the gsx750, more refined and sharp than the BMW k750, and preposterously more nimble than the Kawasaki gt750. The impulse at very low speeds ran circles around the RF900F for nimbleness but the smooth sharp turns at open road speeds made the fr900 very attractive. What were the true limits of the RF900F I do not know, wisdom got the better of me. I was riding for the street, and I could quite easily imagine being caught out on a day with the flu coming on and loosing my licence because I cruised past a cop at 210 on my way to work. Or potentially crashing at stupid speeds because I was exploring the 900's limits. It also cost twice my annual income at that time. As I've gotten older and heavier, I find myself riding ( the Impulse - still) more upright, with less hang, but slightly more drama ( dancing front end) at times. And slower… . We are now both classics. In the rain less hang, more upright, bike leaned more than rider, means better visibility, and more time to react to road surface issues. It's not pretty and can feel wrong, but it's saved my bacon. But when the air is clear, and the surface is wet, hanging off the inside bike more upright gives one just a tiny edge if traction goes bye bye due to slick surface conditions. Old bold riders have learnt to ride through the problems ahead, by adjusting their style to the bike, the road, and the weather, in addition to their rapidly degrading mental and physical agility.
  8. 2 likes
    That is a pretty bold statement. I disagree. There still needs to be a willingness to go fast, a level of tolerance for speed and G forces, and the visual and processing skills required to be located on the track and in control of the machine, not to mention knowing where to point it. IMO making the bike easier to ride helps free up attention and reduce crashes but won't make an average rider a superstar. Just look at today's bikes, you can buy a crazy high horsepower bike right off a showroom floor that has clutchless shifting and traction control and even electronic suspension, but move an average rider from an aged 600cc bike to one of those and see how much faster the rider really goes. Or just watch a superstar kid on a 1990 RS125 making mincemeat of a bunch of adults on 200hp liter bikes with all the electronic assists, you can see that often enough at a typical track day or race practice. I do agree that riders who learn on bikes that do all those cool things would struggle on an older bike without the electronic assists - just like many teenagers today wouldn't know how to operate a manual transmission car - but that could be overcome with some training and practice, I think the best riders would still rise to the top in either situation, I don't think the bike makes the rider.
  9. 2 likes
    I get the sensation of "pushing" the bike up as a countersteering input coming out of the corner. If you remain in your "hang off" position or even exaggerate it on corner exit with your upper body, you really have no recourse but to countersteer the bike back upright out of the lean. For me that movement of putting bar pressure on the outside hand ( and pulling with the inside hand) could be interpreted as "pushing" a bike up. It's not a subtle sensation. Sometimes you'll have to really "push/pull" to straighten the bike up to get ready for the next corner. Maybe you are essentially saying this...
  10. 2 likes
    Here is a snippet from Keith in Twist of the Wrist II that I think applies, this happens to be about choosing a line through a corner: "The "everyman's ideal line" does not exist, and it never will. Different lines are the rider's own personal way of seeing and doing his job: A concatenation of his strong and weak points, dos and can't dos and machine limitations, and, of course, his SR threshold." I think this is why we call it the "art" of cornering, and to me, the differences in riders' style and application of techniques is what makes racing so interesting to watch - and the sport itself so fascinating.
  11. 2 likes
    There is an absolutely perfect description on Twist II that discusses quite specifically both side of this issue, see Chapter 5 Throttle Control, the first section "Street Lazy" followed by Off-Gas Results, it talks about why riders coast, where and for how long, and the exact effects.
  12. 2 likes
    When tire is very worn and the rubber is thin it is much harder to heat up the tire and keep it warm, that is the biggest thing I notice on a very worn race tire, or in some cases the tire profile is changed through wear which can change handling.
  13. 2 likes
    Riding a curved on-ramp at the speed limit with a cop behind you.
  14. 2 likes
    it's all relative. Maintenance throttle in turn 8 at willow Springs on a SV650 is 100%
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    I think I read that in TotW and/or from Level 1 training. Aim for a weight distribution of 60/40 Rear/Front bc our rear tire has more rubber on the road. Something got me thinking about that today and I'm now having trouble making sense of it. I think I've heard about people using setup to get *more* not less weight on the front to improve turning. I thought the logic there was that more weight on the front tire generates more heat and also gets a bigger contact patch. Why would we use throttle to reduce both of those things on the smaller front tire? It seems to me like doing so would simultaneously increase the risk of a high side as well as a low side. There's probably a lot of nuance and subtlety there but I'd rather ask for clarification than assume I figured it out on my own and then risk doing something inadvisable on an indirect route to the hospital.
  16. 2 likes
    OK I read back through this whole thread, and yes, bringing in Throttle Control Rule #2 seems to have added some confusion, as I personally got stuck on trying to discuss the throttle control rule. After reading back over it all, it seems that the OP's real questions was, does it really cause any problem to let off the gas fast or pull in the brake abruptly, it seems like people do it all the time.... I think the answer to that is situational, depending on how much traction you have and how much you are willing to upset the chassis. And also, of course, how fast you need to slow down, and how accurate you need/want to be when setting your entry speed. Example, if you are riding your S1000rr in first gear, wide open throttle, 12,000 rpm and you instantly chop the throttle you will feel a very abrupt change in the bike, potentially enough to affect your accuracy in an upcoming turn. However, if you are in sixth gear at 4000rpm, wide open throttle, and let off abruptly, that's not going to be such a violent change, it may not bother you to rock the chassis that amount. The weight shift is even more pronounced with braking, of course; but it is a matter of priorities. Upsetting the chassis with abrupt brake application may very well be worth it, especially if you need to get it slowed down in a hurry. For sure I can think of corners where I am coming down from high speed to low speed, traction is good, I am straight up and down, where I let off the throttle and bring in the brake as fast as I can - upsetting the chassis is OK with me, I know the front will dive down hard, but my priority is braking in the shortest possible distance and the majority of braking is done at the beginning and I need time for gradual release as I enter the corner. But I can also think of places where I am entering a corner leaned over, or the surface is bumpy, and I apply the brake more gradually to maintain the best suspension/traction scenario, to avoid bottoming the forks or overloading the front tire. One thing we have been taught is that if you slam the front brake on so fast that there is no time for the weight shift to the front tire to increase your traction, you can slide the front tire. Is that a problem? Maybe not, if you are going in a straight line and don't scare easily. Lord knows we see pros doing some really scary things on the brakes, things most of us don't really want to have happen on a Sunday ride (like stoppies, rear wheel hop, back end wagging around, back end stepping out, etc.) I'm going to run this question by Dylan and/or Keith and see what exactly Dylan was trying to communicate and get more details on different scenarios - braking while leaned over, wet conditions, etc.
  17. 2 likes
    Think of the muscles in your back and your abs, as ratchet straps that support your torso. If you don't tighten them evenly, one will be overtightened. In most cases the lower back contracts to far leading to pain and loss of strenght.
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    Surely the law in your country allows you to practise your religion! ?
  19. 2 likes
    I found 2 exercises made a huge difference in my ability to ride without fatigue. They're both hitting the same area so you can do either one. Romanian deadlift and back hyper-extension. You can buy a kettle bell or some dumbbells for the deadlift and do them at home. If you belong to a gym, the hyper-extension allows for greater isolation but they both work great. Start light and do 20 reps a day for a couple of weeks. I found it not only made riding easier but also improved my posture. I'm never tired, my wrists never hurt, my back is strong enough stay low and move side to side without issues. Interestingly, I my fitbit records my rides as cardio.
  20. 2 likes
    Unit came in last Saturday. Was a good weather day so went riding of course. That evening I reviewed the instructions and on-line videos Heal Tech has. Then I began stripping of side panels, seats, fuel tank, and airbus (these steps by far are the most complicated and time consuming of the install, so if you can handle that you can install one of these). Next morning (Sunday) I spent some time deciding how to route cables and locate things. Basically you have the coil harness and module, shift rod sensor, and actual QS Easy module. The coil harness connects between spark plug ignition coils and the bikes coil harness and then to a negative ground. This then has a lead that routes back to tail section where main QS module lies. Sensor is installed on the shift rod and connected back to unit in tail section. That's it except for putting everything back on bike. Setting up and monitoring it is done through your smart phone!!! Other than the initial setup process and some playing with bike on stand, haven't gotten to ride on street as its been raining. Once I get out on road will give a report back. https://www.healtech-electronics.com/products/qse/
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    I do this myself. The most useful thing that I get is the "picture in my mind" of what the track is like. One of the things I have noticed however is once you actually get there reality tends to be a little different than what you were expecting. As Hotfoot mentioned there's lots of things that don't come across in video such as elevation changes and also logistics of moving around on the bike. A really good example of this is the elevation change on the long straight at COTA. I was really looking forward to blasting down that straight at 180+mph with a gigantic smile on my face but the elevation change caused a complete lack of visibility and that does not come across very well in video. Needless to say the first few sessions I was not doing 180 due to the visibility. I actually ended up enjoying the shorter straight near start finish a lot more. Although the speed was slower having a massive up hill elevation change made it so you barely had to touch the brakes to be at the perfect speed to enter the corner at the end. It was like having your cake and being able to eat it too. All the front wheel lifting acceleration you wanted without the chore of having to get on the brakes hard. One other thing which is amusing that I have had a fun experience with. Video games. I have a video game with Road Atlanta as one of the tracks. I was able to put in blistering lap times on the video game and could not wait to ride the track. When I rode the track the reality was quite different from the simulation. I won't bore you with details but I have yet to ride Road Atlanta again despite it being so close to my house because of how horrible of an experience I had. I actually think that my game play slightly hurt my ability to learn the track with an open mind. Certainly watch the videos and study the track maps but be ready to actually learn the track by riding it yourself. Most importantly be ready to adapt when the reality becomes different than what you were expecting.
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    One thing I will mention - there is limited info available in the video above. You can hear the engine, see the rider's line and observe lean angle, but one thing you CAN'T tell is the relationship between the rider's throttle-hand INPUT and the engine response. So in the video above when you hear the engine rev up, it sounds odd in some places, like it revs up very quickly then flattens out a bit. That could be caused by traction control intervening (if it is present on this bike), by the tire spinning, maybe even by the clutch slipping - clutches wear out quickly on high horsepower race bikes, race starts are very hard on clutches - it is hard to tell without seeing data that shows throttle input. On the Superbike School student videos the camera is positioned so that the rider's hand is visible on screen, so it would become immediately obvious whether the rider's throttle input was smooth and consistent or not, plus the BMWs can tell you the actual difference between throttle INPUT (from the rider) and OUTPUT (after any traction control intervention) and the data logger can show tire slip rate, too, all of which would make it easier to analyze the video.
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    Oh I like it! The "riders prayer". We should write a cool one a post it up.
  24. 2 likes
    Cool story. Read this: https://www.scientificamerican.com/article/the-bicycle-problem-that-nearly-broke-mathematics/#
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    This interview with me appeared in the April issue of Roadracing World magazine. I thought you might like to see it. John Ulrich was kind enough to give me a PDF version of the interview for you to read. http://superbikeschool.com/files/code-rw-interview.pdf The file is 600K and requires Acrobat Reader 5 or newer to view it.
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    Traction Science Traction limits are hard to reckon for most riders but there are some things to know about it. Traction results from a brew of chemicals the rubber is compounded with, how cleverly the carcass is constructed and shaped, proper inflation, enough tread depth, and maintaining the tire within its optimum temperature range, which varies with different rubber compounds. Heat up a mounted tire to its operating temperature, tilt it over to 45 degrees and apply ever increasing pressure on it. At some point the tire will slip; that amount of load is 101% of the tire's static grip limit. In motion, achieving maximum traction is quite different. As the tire grips it wears. What 'wears out' are the various chemicals, oils, waxes and pigments which bind together the rubber. Abrasion and heat 'cook' them off. You've noticed the bluish-purplish color of a tire from hard cornering, it's called 'blooming'. That is the residue from the chemicals which have been leached out of the tire from heat. It takes very little abrasion to wear it off, maybe a lap. The oily parts—in sufficient quantity to maintain the rubber's flexible and compliant character—support its ability to mate with the road's surface. When they 'cook off', the tire becomes dry and slippery, like dead skin peeling off a sunburn. That sun-cooked layer must be cleaned off to expose fresh skin, or, in this case, fresh rubber. Cleaning it off requires abrasion. The amount of abrasion needed is provided by tire slippage. Tire engineers agree that roughly 15% longitudinal slippage maintains friction value peaks which includes maintaining peak operating temperature. You'd be mistaken to think this 'slippage' is a 'slide': in a corner, the bike is holding its line. It is what is needed to achieve peak traction; considerably less slippage is needed for cleaning it. Depleted rubber must be scrubbed from both tires. There being no power to the front it relies on three forces: 1) slip angle, 2) side grip friction, and 3) abrasion from braking, to uncover fresh rubber. In the steady state part of a corner (after braking and before acceleration) both tires clean up from slip angle and side grip abrasion. Slip angle is interesting. If you were able to freeze the lean and the turned-in front wheel angle you have while going through a corner, then got off and pushed it, the line would be much tighter than when you were riding. The bike's tendency is to always go straight—until some outside force influences it to turn. The turned-in front wheel is that influence—it creates abrasion resistance which forces the bike to go into and hold its arc through the corner. The tires are actually slipping sideways toward the outside, hence, slip angle. The side-slip in skiing is similar. But that's not the whole picture. Camber Force is another factor. Although it has substantially less effect on tire wear, it plays a part in traction. It works like this: On both tires, the outside of the patch (the chicken stripe side) is on a tighter radius than the side that's closest to the tire's center line. Think of a playground merry-go-round. The outside is traveling further in the same amount of time as the inside and therefore going faster than the inside. Conversely, the side of the contact-patch closest to the middle of the corner, is turning slower and is dragging. This creates rubber-cleansing abrasion and also helps the bike stay on its line. (To find more data look up the technical definition of camber thrust or camber force.) In any corner and at any speed sufficient to keep the bike moving and balanced, the tires are always slipping, at least slightly. You wouldn't get through corners or have to replace tires if they didn't. © 2014, Keith Code, all rights...
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    bingo - that's it in a nutshell. I think it's the quintessential dilemma for most aspiring riders: how much faster can I go before it results in disaster? If it truly ISN'T a knife-edge limit, then I guess it comes down to the combination of a machine that's set up in a way that lessens the abruptness of the loss of traction (when that slip vs feel non-linearity becomes uncomfortably exponential), and a rider's willingness and ability to ride through it. the last part is why is finally decided to cough up the big bucks for two days at CSS at Laguna. I guess I was just interested in first hand testimonial from guys/gals that do ride deep in that slip zone. I think at your school in Laguna you will be pleasantly surprised to find out a variety of ways you CAN go significantly faster WITHOUT having to slide more. Your personal style and setup may end up including a greater or lesser degree of sliding, depending on your preference, but for sure CSS will give you tools to predict, and manage and/or avoid sliding. As far as personal experience goes - I am obviously not riding at MotoGP level, but I am racing competitively and I don't slide much at all. I pass a lot of people who are sliding a LOT, and often I can see errors in their technique that are causing the slides. Here are some things I see a lot in races: - trail braking and too much tension on the bars causing front end slides - over-braking, getting the corner entry speed too low, then whacking the throttle on too hard mid-turn and sliding the rear - braking hard with tension on the bars causing the back end to wag around or step out - crossed up body position resulting in excessive lean angle, combined with imperfect throttle control, causing front or back end slides These are the ones I see the most and are the most obvious but there are other reasons having to do with line selection, etc. For me, the more schools I attended, the more confidence I had in what the bike was going to do - so the limit seemed less and less like an unknown sudden-disaster possibility. Getting educated and getting the survival instincts under control does WONDERS for confidence and control.
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    Body Position The most obvious thing about any rider is their form on the bike. How do they sit and move on it? What’s their posture? Do they look comfortable or awkward, stiff or loose, Moto GP, or nervous-novice? Good body positioning isn’t just about being stylish——you can play dress-up in your older brother's or sister's cool boots but walking will be clumsy——it has a desirable result and we can define 'good body positioning'. Harmony with the bike, freedom of movement on it, precision control over it―with the minimum necessary effort. Survival Reactions Play a Role The bike itself can force poor riding posture. A shift lever positioned a ¼ inch too high or too low manipulates the rider into awkward and uncomfortable poses, limiting his control over it. Even with perfect control positioning, good form on the bike has its difficulties. Achieving it may look and even feel like it’s reserved for the young and flexible. This may be true to a degree but many of its problems are actually brought on by our own Survival Reactions, our SRs. For example, a rider who instinctively levels the horizon by tilting his head in corners, creates unnecessary tension in his body. Basics Apply Good form is difficult for riders who struggle with basics: uncertainty with basics has a physical manifestation. Just as joy or anger are obvious in someone, these uncertainties manifest themselves in awkward and unsuitable body positions. For example: poor throttle control prompts riders to rely on slash and burn hard drives out of the turns. Their 'ready-for-action', rigid body language telegraphs their intention. That tense anticipation of the drive off the turns loses them the handling benefits of being relaxed mid-corner. The Stages of Body Positioning There are three stages to body positioning: Poor form + poor riding = ripple-effect, snowballing errors. Good riding + poor form = good but limited range of control. Good form + good technical riding skills = riding that is both fluid and efficient. Number 3 is the goal of any rider training. The Ingredients Body Positioning has five distinct ingredients. The bike and how it is configured——its controls, seat, pegs and bar positioning. The rider's understanding of body positioning——how to properly position himself on the bike and why. Our Survival Reactions——how they create unwanted and often unconscious tension and positioning problems. Lack of riding basics——has or hasn't mastered the core technical skills needed to ride well. The rider's own physical limitations——height, weight, flexibility, conditioning. With those five points under control, specific techniques can be employed to achieve positive benefits in bike control. Form, Function and Technique GP body position does not address or improve 90% of the most basic and vital components of riding: Our sense of traction, speed, lean angle, braking, and line, to name a few, are not directly dependent upon or necessarily improved by stylish form. Clearly, body positioning isn't the universal panacea some think it is, but it has its place. For example, holding the body upright, counter to the bike’s lean while cornering has several negative effects. Among these, is the fact that it positions the rider so he can’t fully relax. This can be quickly corrected and solves the functional problem of tension from cramped and restrictive joint alignment: a key element in allowing any rider to relax. A bike related example would be too high or too low brake or clutch lever. It puts the rider's wrist into misalignment and restricts fluid movement. The Rules of Technique Here are my guidelines for technique. Any riding technique is only as good as: The validity of the principles it rests on. Example: The benefits of hanging off follow physics and engineering principles. The access it provides to the technology with which the bike is designed and constructed. Are the potentials of chassis, suspension and power able to be utilized as intended? Does the technique embrace them? The consistency with which it can be applied. Does it work in all similar situations? The degree of control it provides for the rider. Can the rider either solve problems or make improvements, or both, by using it? The ease with which it can be understood and coached. Does it take extraordinary experience or skill to apply it, or, can it be broken down into bite sized pieces for any rider to master? Which brings us to my first law of body positioning. Stability Comes in Pairs. Bike and rider stability are always paired―rider instability transfers directly to the bike. Body Positioning has but one overriding guideline: Rider stability. How a rider connects to the bike can bring about harmony and control and fluid movement or turn into an uncoordinated wrestling match. Ideal Stability Having stability AND fluidity of movement sounds conflicting; when something is stable it’s expected to stay put, unmoving, like the foundation of your house or the roots of a tree. But the opposite is true for riding. Comfort And Stability What works well on a paddock-stand doesn't always transfer to real riding. Aftermarket rearsets, which can be adjusted (or which are manufactured) too far up, back, forward or down is an example. In the paddock they feel racy; on the road or track they can fatigue the rider. The fatigue comes from the rider's core not being correctly supported. This causes him to be off balance. Off-balance generates extra effort from muscle tension and poor joint alignment which in turn hampers accurate control manipulations. Awkward looking body position is what you see. Riders often accept or try and work around this, without realizing its negative impact on their riding. Simply Complicated Through research and coaching of tens of thousands of riders of all skill levels, 58 separate elements which influence our body positioning have surfaced. Seemingly simple things such as too tight a pair of gloves or leathers can affect all the other elements. Once the 58 are corrected and integrated, the rider has many more options; opening doors to a wide range of fun, efficient and, you might say, elegant techniques. All of our coaches have been thoroughly drilled on what each of the 58 are and how to correct them. © 2014 Keith Code, all rights reserved. This article may not be reproduced in any form without the author's consent.
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    If you read through the article I posted a link to, it concludes that wider tires primarily are for wear reasons. As we all know, a rubber tire sacrifices itself to provide the friction (all the gum balls on your front tire after a track session prove this is so). A small tire dealing with significant friction demands, and in drag racing probably being overloaded will wear fast. So if you had the smallest tires that could support the weight of the car and did a run, you would likely destroy them due to friction heat and mechanical stress. If you were really serious about winning a drag, you could have single pass tires that had just enough strength for a run and then die. They would be smaller and lighter. But you would change tires every single pass. So the extra rubber is for wear and handling of forces - vertical, lateral, roll on the sidewalls/carcass, flex to absorb acceleration and deceleration shock, bumps and so on. It doesn't provide more friction or grip.
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    Interesting analogy and it makes me wonder how technology has improved that area as well. I haven't squeezed a trigger in many years. I enjoyed it as a personal challenge. I trained in the profession as a U.S. Marine. One of the things that we were told in Recruit Training is that during bad weather, scores tend to dampen. I took that to heart and wanted to do the opposite; nature obliged my request as I seemed to always be at the range and shooting for score (a component of career progression) during cold and/or wet. Save my score from Recruit Training (Sharpshooter), I've always qualified and added an increasing sequential number to my Expert badge. In my day, just a short 14 years ago we fired weapons with only open sights, the old fashioned way. I saw a video of more recent Marine Recruits using optical sights on their weapons. I was horrified. What had my beloved Corps done??!?!?! Well, I guess that's the way of progress. The thought had occurred to me that it's possible that the technology has a positive effect on accuracy and battlefield engagement outcomes. I don't have the data to support that, but I'm sure there was an Army surplus somewhere and the Marine Corps picked them up to try and make some good use of them.
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    I am not actually dissing hanging off - it will make it possible to corner a bit faster. It will not gain you many seconds per lap, but it will gain maybe 2-3 on average for a top rank rider (me speculating here). Of course, even if it's just a tenth it's worth while. However, I think there are far more important aspects for riders to learn than hanging off. If someone goes faster than before with considerable less lean when the rider start hanging off, it does not (me making a statement) have nearly as much to do with the riding position as with the rider having improved other things (see MOTORRAD figures for what hanging off brings). Also, for street riding, hanging off has disadvantages that, for me at least, outweigh any benefit of leaning a bit less; it is tiring, it usually means you cannot see as far around a corner, and it can make it harder to change direction for something unexpected. But I'm sure there are those finding it worth while. Anyway, it all boil down to this; I believe hanging off is credited for more than it can actually deliver. It is no doubt an important tool for the expert rider, but again I think there are a lot of things that can help much more when it comes to riding safe and fast. Here's a video of Mike Hailwood racing a Ducati. It's fun to watch him going quicker through the esses, despite having a chopperesque amount of wheelbase, rake and trail. The Ducati also made substantially less power than the Kawasaki and Honda that came 2nd and 3rd. It would be very interesting to hear what the coaches think is the main reason why Mike goes that quick compared to the competition, as I do not have a clue.
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    There are many ways to Rome. This is a good interview on comparing Vinanles and Lorenzo's styles. http://www.crash.net/motogp/interview/269077/1/exclusive-wilco-zeelenberg-yamaha-interview.html Doohan did a lot of things "wrong" and won a lot of titles. Hailwood came back and used the classic style to beat more contemporary riders 15 years on. Personally, I do not believe there is one universal correct way, and everything else is more or less inferior. Perhaps if all riders were computers, there could be a universal "right". But in the real world, people differ. They learn to compensate, they learn little tricks. The rider's weight, strength, agility, flexibility, reactions, preferences and more will all influence how fast a rider can go and how he or she can do so in the best way for them. In that respect, I think Hotfoot is right on the money. CSS will teach every person a way that will work, safely and efficiently. Level 1-3 will not be enough to make a world champion out of anybody, and the majority will not even be able to take full advantage of the basics they CSS teach them. But for those with the will, determination and skill to move forward, CSS and their level 4 can no doubt help any rider at any level break through new barriers and continue to improve what they already do best. Not knowing any of the CSS personnel in person, and certainly not Keith, I think it is still safe that they would not try to make Marquez ride like Lorenzo or vice verse. Instead, I believe they would focus on each rider's strengths and improve them further while also trying to knock back on the odd weakness so that they can become even more complete. I could, of course, be wrong. Again
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    S1000RR only 160# lighter. Must have titanium front forks, magnisium frame, ECU that takes on the fly verbal commands, 3" narrower seat, with 1 1/4" less padding, cornering headlamps, self heating elements on axles to feed heat lined carbon wheels (eliminates need for tiee warmers by heating the wheel and tire casing from the inside), red, white and blue everything, and a voice activated digital readout to talk to riders or students behind you.
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    Forgot to report back that examples of the roll rate can be found on the Twist II DVD.
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    My theory is that the top out spring in my 2006 CBR1000RR fork is not only progressive but it's variable.Full range of travel yields 16mm of preload adjustment from all the way out at 0 to full stop.At full out, the installed preload was measured at 8mm. At 6 turns it's at 9mm and at 12.5 turns it's at 15mm.Someone please explain to me what's going on here. Aftermarket springs are 260mm, stock was 217mm (from memory). The preload spacer was cut from 100mm to 73mm
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    are the "articles" archived? i remember one a few months ago (about weighting the foot pegs) and i never saved the email. gotta believe that good stuff is saved somewhere... and i'd like to re-read that email.
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    Yes, that got fixed! I liked your post.
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    Not sure if you ever looked into it but it's a bike trainer where you remove your rear wheel and hook your bike directly to it. They have heavy flywheels to help mimic "road feel" and they work great when paired with an app like zwift which let's you ride "scenes" and push yourself against all the other zwifties from all over the world. That said, I found that it's still a bit of a drag to ride indoors. Better than traditional trainers but still not the same as zipping around outside in nice weather. I only used it 6 or 7 times so far. But I'm happy to say I did get back into the gym and even took a good look at my diet. In the last 4 weeks, I've dropped 10 lbs and 5" off my waist. As for riding, I've just been riding my fav mountain road to work every dry day and a few wet ones too. Looking forward to some track time. Traded in my Boxster for a tow vehicle bc riding to a track day is brutal.
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    Ha ok. Well the socks I'm currently wearing are samples from a manufacturer that were sent to me for testing. I have been a huge fan of bamboo and my favorite socks are no longer available. So out of sheer "being totally desparate" I'm testing out as many yarns as I can as I'd like to make my own socks specifically for riding. So far I'm on day 3 of wearing them and they still smell like roses. They are unbelievably soft as well, pretty much like walking on clouds. I'm going to wash them a number of times to see how they wear, but I've been told they stay soft just like my bamboo socks did. Another bonus, they are supposed to be extremely durable. I can show you the fabric end of this month when I'm at CSS but they will be well worn by then so beware hahah. I looked up "tencel socks" and there are a few companies that use the yarns so I think in the mean time I'll find a good company and buy my daily wearers from them. I truly don't think I can go back to pure cotton, poly, or nylon. Especially cotton.
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    And this is a little harder to observe in the modern era (throttle roll on) with the electronics. They could roll on a lot, but the bike might not give them full amount...again, the modern era.
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    Call the office for that: 800-530-3350
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    This track is only a few hours from home. Have never been there. Has the school been there before and does anyone have any opinions of it? I love VIR but is a lot longer drive.
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    HI All, There is a difference in the upcoming single day school at COTA, that is worth a slight mention: normally we run a 1-3 ratio of coach to studes at our single day schools. Since that track is so long, and we want to make very sure we get good service to our students, we are going to actually run LESS students than normal. The ratio will be 1-2, coach to student, and that will mean only 18 students on track at a time. That'll be pretty nice for the guys on track. I've completed today's shameless plug, cleverly disguised as "relevant information." CF
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    Aliki just reminded me of a time when I was supposed to goto a girlfriends house. I never made it. I nearly got swiped by a drunk driver that I "sensed" behind me and to my left, passing me. I watched the car fishtail a few feet in front and pinball off the guardrails. I decided to go back home after that experience. Ever hear: God takes care of babies and fools?...I haven't been a baby in a long time. My pre-ride prayer "...that I make good decisions and those around me make good decisions (and the rest is left up to The All Knowing)" has worked up to this point. I'm now reading "Proficient Motorcycling" so that I can do better at keeping up my end of the bargain (good decisions).
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    I feel like I accomplished something by finishing that story. (if you read the story you'd understand- LoL)
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    Bummer. I would slow down to 75% and revisit counter-steering. Press on the right bar to turn right, and left to turn left. You can't possibly quick-flick the bike any other way. The Twist II DVD illustrates the comedy of body steering and peg weighting as steering tools. Peg weighting is great to lock on to the bike and facilitate pivot steering-push with your quad muscles into the tank on one side, and press horizontally on the bar on the other side. Also, ensure your body is low enough to make your counter steering effective; it is possible that you are pressing down on the bar instead of horizontally, making your counter steering ineffective or inefficient. Paying attention to riding can be tough with new life events. A new job and a newborn will demand attention; riding fast, like any sport, is a mental game and the athlete pays a price when not focused. Best wishes.
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    CRASHING Riding errors which lead to crashing follow distinct patterns. Once detected they can be used to make huge leaps forward in skill and confidence. Reasons To Improve My experience is that riders come to school for a variety of reasons. They say: to be safer, faster, more in control, learn the skills, have more confidence, get their knee down, improve and so on. Beneath all of these reasons and consistent with each is a very fundamental personal reason: riders don't want to crash. Everyone wants to experience the maximum freedom and exhilaration with the minimum of danger; and I fully agree with this. For the school staff, this principle works out just fine. If a rider crashes on a school day, no one wins: we are deprived of the opportunity to finish up what we started and so is the rider. It puts kinks in the day for everyone involved. Conventional Wisdom On Crashing Unfortunately there is still a lot of really bad advice out there on crashing: "You don't know how fast you can go until you crash," is one of them. "There are riders who have fallen and those that are going to fall," that's another one that makes crashing seem inevitable. These pieces of "conventional wisdom" miss the mark by miles. They are actually harmful. I'm not saying that you can get through all of life without falling down. You may. But riders have and will continue to crash, bin it, fall down, go down, throw it away, pitch it, drop it, put it down and lose it. A significant rider error, when aggravated and compounded by the rider's "corrections", can result in violating the machine's inherent stability leading to a bike and rider going down. That is the negative. Errors Follow Patterns On the positive side, there are key indicators of these basic errors and they follow a pattern. I say positive because if you intend to improve someone's riding, but don't have a clue about these indicators, you may see errors and try to correct them but miss their underlying pattern, which in turn creates a mystery as to why the rider suddenly runs off track, scares him/herself or falls down. These indicators do have patterns and are specific in how they look. They generally break down into two main categories. 1) the riders who look uncertain and choppy as they commit them, a sort of advanced case of new rider syndrome and 2) riders appear to have abandoned their senses like someone with their first unlimited-purchase credit card. They are purposeful, very positive and absolutely committed to their silly riding. You see what can only be described as blind faith in the bike and the tires with absolutely no idea of limits and how these limits may be correctly approached and eventually controlled. Steering Drill Those of you who have already done the school may remember the simple steering drill we did with you in the paddock or skid pad area. There are 6 corrections we can make on how the rider relates to the bike as it's steered into a corner with that drill. Riders feel more in control of the bike from any of the six corrections, once corrected. However, one of the primary reasons we do the steering drill is to prevent them from making mistakes that, under very common circumstances, can lead to running wide, running off the track or even crashing. When the coaches see these errors they know where the rider is going and what he thinks he is trying to do and how bad it can get if not corrected. The Timid and The Brave Some riders can't get comfortable with the no limits idea the track provides and actually ride slower than they do on the street. While at the other extreme, some riders go on vacation from the laws of physics, speed, lean angle and common sense. Whichever mode they tend toward, certain patterns quickly develop in their riding that, to the trained eye, spell TROUBLE. I hope I don't blow any other schools out of the water with this but, all schools, all track days, all racing and of course street riding have crashes. Some people call them accidents but rarely are motorcycle crashes accidental; they are caused, more often than not, by the rider's own hand. Statistics on Crashing I bring this up because of what has happened at our school over the past year and a half. For the previous 25 years we had a pretty consistent attrition rate due to crashing. All in all it wasn't horrible, about one and a half million school miles to what you might call a serious crash: more than a broken collarbone or bruises kind of thing. Because we pay attention to how riders are riding I was convinced it had more to do with the phases of the moon or something than observable riding patterns but we've had a fresh look at this and it began to resolve in the riders' favor. Once we began to really see the errors and what they meant, what seemed like accidents or fate turns out to be lack of technical skills and is very correctable. What happened? Well, when you have a 50% improvement in anything you know that you are on the right path and we have, on average, cut our crash rate in half. Considering that we have more school days and hence more students now than ever before, that floats my boat. Preventative Measures We are becoming pro at spotting these patterns and nipping them before they progress to the run-off-the-track or crashing stage. Looking at it from another perspective, students have told me for years that crashing on the track is most probably many, many times ?safer? than on the street. But one of the great rewards of teaching this sport are the scores of students who have come back and told us of the horrible riding situation that they avoided because they knew what to do. I'm not saying that we can make you a safe rider. I'm not saying that you can't crash at my school, you certainly can. Fortunately, we recognize something about ourselves and our sport: if riding was not dangerous it wouldn't be nearly as much fun. We know the risks, we like the risks and we love the rewards of taking them. It makes perfect sense to me. Taking risks, with understanding, makes a rider as safe as he or she can be. Problems Lead to Improvement The other huge positive that has come out of this evolution is that riders are made more aware of the points that get them into trouble. It may sound crazy but more often than not the "fatal" mistakes (resulting in poor control or catalysts to crashing type errors) mistakes are actually aspects of riding that the student felt were some of their best points. Clearing up these misguided ideas alone can open the door for vast improvement with any rider. If this seems like I'm patting ourselves on the back, you are right. Crashing is a huge area of rider fear and eliminating 50% of the crashes on average is another milestone for us. You have plenty of reasons to learn the skills of riding. We are doing our level (very) best to see that you get what you want with your riding and we are winning at it every school day. You will too. See you at the track. Keith Code Copyright Keith Code, 2006, all rights reserved.
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    Hey buddy. Glad you have the same brain as me and you are interested in this topic. I don't really agree with your statement though. A wider tire will suffer a greater difference between "visual lean angle" vs "effective lean angle" at all angles. In fact, at moderate lean angles such as 20 degrees I think the thick tire would suffer a bit less since your contact patch is still towards the center of the tire. As you lean farther and farther you get to the edge of the tire which can create a big difference between visual and effective lean angle. I drew up a picture of a bike leaning to 90 degrees visual lean. Note that effective lean angle of 90 degrees can never be reached. You MUST have an infinitely thin bike and tires. Something very magical happens as you get close to 90 degree effective lean angle. With "out of this world" tires you could get to lateral G's as high as you want as you approach 90 degree lateral G's approach infinity. In other words, you could never lean the bike 90 degrees even if you had infinitely thin tires and blke because even when pulling 10,000G's the force of gravity will pull your bike down at 9.81m/s^2. At 89 degrees lean angle you would need to execute a 57 lateral G turn and it would actually be possible if your tires can have that coefficient of friction and your body can withstand it hahaha It is very sad that bikes and their physical dimensions only allow a 60 degree lean or so. Once you get past 60 degrees things can really get nasty - in a good way! The difference between a 60 degree and a 70 degree lean is at 60 you do 1.7G's and at 70 you do 2.7G's!!! At 80 degrees you could do 5.6!!!! At that point we can corner better than a F1 car!!! It's almost as if bikes have hit this barrier where they are not limited by grip of the tires. They are limited by physical dimensions and the amount of lean possible according to those dimensions. As better tire compounds advance through technology, we will never benefit in terms of mid-corner phase (mid corner speeds) but only in the aggressiveness of our trail braking / power out of the corner. Mid corner speeds are sort of set in stone, nomatter what we do with our tires. A cool thing about a bike that is mentioned briefly in Code's article is it has built in "aero" in the turns... Most racecars need a fins to generate artificial gravity (downforce). The problem with fins is that anytime you create lift (down or up lift) you create drag which slows those cars on the straights. On a bike when you turn the resulting force travels through the bike. In other words, the bike gets sucked into the ground the more you lean. Just like in geometry, when you do a 45 degree lean, like a 45 degree triangle, where the opposite, and adjacent are 1, makes the hypotenuse 1.4. At 45 degree lean, a bike and rider that weigh 600 pounds would put a force on the tire of 600*1.4 = 840 pounds! That's alot more grip!!!!!
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    I know how you feel when you say that you will need to quick turn the bike until you break traction to find the limit. I used to feel the same about lean angle when cornering, I didn't know the limit so I thought the only way to find it would be to crash... But that kind of thinking is just plain wrong - and dangerous! I got a good bit of advice from Brendan Clarke (he won the Australian Superstock 1000 championship last year), I asked "how do I find the cornering limit? How do I know how much I can lean?" The answer is very straightforward and there couldn't be a more logical method when you think about it. The answer was to simply keep increasing your cornering speed gradually, bit by bit. If you enter a corner at 100km/h on one lap, and observe that the bike was settled with no problems then then next time around you can enter the corner a 102km/h, if all is well then continue entering the corner faster, 104, 106, 108km/h... (it helps to keep the same braking marker to avoid changing too many variables, just set your speed and maintain it until the corner, then you can more easily focus on your entry speed and turn point.) Actually that may be best to learn how fast you can enter a corner, but for actually practicing quick turn you probably don't want to change your entry speed, just move your turn point further back each time... even less variables that way, much easier. If you take it gradually like that you won't ride over your limit. When the bike is getting close to the maximum cornering ability it will give you some warning signs before you completely lose traction - for example you'll get a bit of a slide, a bit of a wobble, you'll feel it's not as stable etc. The thing to remember is that you won't just 'lose traction' in a corner. (Of course assuming clean track surface, warm tyres, correct use of bike controls etc.) There is a 'traction zone' that moves from static friction to sliding friction, it's not just one or the other - there's a transition in between. It helped me to stop thinking primarily about lean angle in a turn and instead think about the feeling of traction, which will in turn determine your lean angle. You can use the same method for the quick turn, if you use a certain steering rate on one lap, and it all goes okay - just increase the steering rate by a certain amount on the next lap, then again, practice, practice... It sounds like you may have a hard time with the other riders you're grouped with, but I'd just try and focus on my own thing and let them ride around you. Even better if you can move into a slower group just to take it easy and practice some drills.
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    It is good you enjoy pinning the throttle and enjoying some speed rush. I think if you change your reference points and begin to roll out of the throttle and start braking a little bit sooner, then you should have your speed better set in time to hit your turn-in point. Properly applied, this should get you turned and back on the gas sooner, give you a better drive out of the corner, and allow you pin it even sooner. As Jason mentioned, the two-step can help with this.