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  1. 3 points
    Here's a short TV spot about CSS. Courtesy of Superbike Planet
  2. 3 points
    A couple of other things to be cautious about. 1. Puddles. Not only because of the hydroplaning potential. Hit one at speed and all the water in the puddle nearly instantaneously will soak you and add lots of weight to you. 2. Tar snakes and patches. Not all traction is created equal. Tar snakes will cause a lot more traction issues when they are wet. Some patched areas have more or less traction than the main part of the track. 3. Visibility. Visor fogging (easily fixed), Mist from other bikes, fog and rain on your visor can reduce visibility. Use a clear shield at all times to avoid this and preferably a clear windshield on your bike to maximize visibility. The straights are a gigantic wind powered windshield wiper for your helmet if you stick your head up in the air stream and move it from side to side. 4. Slippery when wet. Controls, pegs, tanks and other parts of the bike are not as easy to hold onto when your bike is wet. Be aware.
  3. 3 points
    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.
  4. 3 points
    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.
  5. 3 points
    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?
  6. 3 points
    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.
  7. 2 points
    Inspired by the mystery of what to do and not do that is involved in wet riding, I thought I'd start a collaborative list of differences and limitations in riding in the two environments. To start what we know: You cannot Quick Turn the same You cannot brake as hard You cannot accelerate as hard mid-corner Anything else?
  8. 2 points
    Personally I love riding in the rain. Less traffic and at the end of the day it's like having your own private track when everyone packs up and leaves early. When other riders are angry and horrified about the R word I'm thinking "heck yea"! Some of the things that change in my riding in the rain. 1. Braking. Earlier, lighter, longer. Stretch out the braking zone and leave yourself a buffer just in case. 2. Lean angle. Less is more. You stay on the fatter part of the tire and maintain more traction. Hang WAY off the bike to reduce lean angle. The more you hang off even at slower speeds keeps you on the more stable part of the tire. 3. Line. It's critical to use ALL of the track available to flatten out the corners as much as possible. 4. Less aggressive quick steer. I have found that you absolutely still can quick steer in the rain if you stay reasonable with it. I worried the heck out of a CSS coach when he assigned me the quick steer drill in the rain. I performed the drill too. I even got a hug when I came back in one piece. 5. Throttle. You have to be a lot easier on the throttle especially when the bike is leaned over. On "analog" bikes once the bike is straight up and down you can use the throttle to "sample" traction. Give it gas and you can feel where the tire wants to spin just a bit. That is the fine line of where the traction ends. Don't cross the line especially when leaned over. (I would approach this with caution!). On bikes like the S1000RR in the right mode the bike will protect you for the most part on the gas. I find that I prefer sport mode or higher in the rain but rain mode is more protective and best to start out with. 6. Smooth counts. Abrupt and sloppy inputs that are ignored because of mega grippy tires are not tolerated at all by the bike in the wet. Stuff to watch out for! 1. Curbing. It's fine to run over curbing in the dry but in the wet that stuff becomes really slick. You have WAY less traction than you do in the dry on painted parts. 2. Panic. If you end up overdoing it don't panic!!!! With less traction the bike is much less willing to be forgiving for sloppy and abrupt inputs. If you enter a corner too fast just extend your braking past the optimal turn point and use the track you have available. Bring the bike down to a manageable speed and turn where you can. Yes you essentially "blow" the corner but by using the track you have you keep it on the pavement. 3. Tires. It's COMPLETELY true what was said about tire temps earlier. Your tires won't maintain temp. Not only are you dealing with the slick surface created by a wet track you are doing it essentially on cold tires. I set a cold pressure and leave it there. You can even experiment a bit with dropping the pressure but I'm not really sure it helps much and can potentially make the bike feel a bit mushy and imprecise if you overdo it. You still won't get a lot of heat in the tires. 4. Your physical condition. Riding in the rain seems easier but you do still get tired. Since you aren't sweating like crazy the fatigue sneaks up on you. I rode every single session of a wet track day only to figure out during the last session that I was a lot more fatigued than I realized. This fatigue can be both mental and physical. Stay sharp!
  9. 2 points
    I thought I knew how beneficial it would be and I thought I knew what I wanted to get out of it. I was kinda wrong on both counts. The personal consultant approach makes the leap between L3 and L4 huge. Take what we all know about CSS coaches. They're well versed in the hangups regular humans have in riding motorcycles fast and they're incredibly skilled at breaking down those barriers and knowing what the riders need to become better. Now, take those skills and remove the confines of teaching 5 new skills in a day and just let them have the time to fix whatever needs fixing and that's the difference between L3 and L4. I was at SoW. I was struggling at the kink and it turned out the problem was actually starting at the turn-in for 8. This was nice but the next revelation was that I was turning too slowly. It never felt like it to me because I was able to hit my marks at the speed I was riding. But much like the previous issue, the solution was not what I expected. I thought once I had more pace, I'd turn more quickly. But once they got me to really turn more quickly, I found that I had to up my pace. Again, the solution to a known problem was far from intuitive. After circling SoW who knows how many times at basically the same pace (better form each time but never more pace), being forced to do quick-turn correctly (in my case, push-pull) forced me to approach the corners with more pace because if had turned more quickly at the same entrance speed, of course, I would have early apexed. This one change got me 9 seconds. Next year I'm going to find a stretch of 3 or 4 days at SoW and book multiple days at once. Primary focus (I think) will be T1. Can't wait.
  10. 2 points
    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.
  11. 2 points
    The slip % should be between 5% and 15%, which it is, and the traction control will keep it in that range. It looks like you are getting a lot of slip % at steep lean, which would suggest that your entry speeds are a little low for your liking and are being compensated for with somewhat aggressive throttle while leaned over far mid turn. I have no clue about Michelins, but would follow the suggestions of the local distributor for that tire.
  12. 2 points
    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.
  13. 2 points
    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.
  14. 2 points
    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.
  15. 2 points
    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.
  16. 2 points
    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...
  17. 2 points
    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.
  18. 2 points
    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.
  19. 2 points
    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.
  20. 2 points
    Riding a curved on-ramp at the speed limit with a cop behind you.
  21. 2 points
    it's all relative. Maintenance throttle in turn 8 at willow Springs on a SV650 is 100%
  22. 2 points
    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.
  23. 2 points
    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.
  24. 2 points
    Surely the law in your country allows you to practise your religion! ?
  25. 2 points
    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.
  26. 2 points
    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/
  27. 2 points
    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.
  28. 2 points
    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.
  29. 2 points
    Oh I like it! The "riders prayer". We should write a cool one a post it up.
  30. 2 points
    Cool story. Read this: https://www.scientificamerican.com/article/the-bicycle-problem-that-nearly-broke-mathematics/#
  31. 2 points
    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.
  32. 2 points
    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...
  33. 2 points
    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.
  34. 2 points
    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.
  35. 1 point
    The overall grip is reduced so anything relying on tire grip has to be backed off considerably - can't lean over as far, can't brake or accelerate as hard, actions must be smooth and gradual so you have time to feel out the traction. And, of course a variable surface (some areas wetter/slicker than others) makes it even more challenging. I don't know much about this source but here is an article I saw that seems like a decent summary: https://lifeatlean.com/riding-in-the-wet/
  36. 1 point
    I asked our chief mechanic at the school, here is his response: >> The eccentrics are in the stock position. There is no "wrong setting". Tearing like that comes from wheel spin. Depending on what mode he runs in or what his traction control is set to will vary the wear. Mid Ohio for sure has some straights coming off right handers and a kink so there's gonna be some serious drive in those spots. The position of the wear would indicate getting on the gas late and hard. >>
  37. 1 point
    Like stated above, if you run out of lean angle and drag hard parts, hanging off obviously helps. Short of that, hanging off might give you a small margin or error to add lean/countersteer if you can't make the corner. Way short of that, you probably should just be in a position as comfortable as possible to make your throttle and steering inputs. For me thats the traditional inside of midline with your outside leg locked on tank.
  38. 1 point
    You bring up a very good point... also I probably misspoke in terms of the loss of friction in respect to the change in the normal force. I will say there's parts I am not very well versed when it comes to the artificial gravity experienced in circular motion so I will make statements clear when I am making assumptions and personal opinions here. One thing to note is that first it's the increase in weight experienced by the rider not necessarily the increased in weight of the bike and the rider. That's not to say the weight gain isn't significant; I just don't know how much... best case let's say only the wheels cause the centripetal acceleration and with the good suspension the rest of the bike and rider experiences the 1g laterally, but can't be the full weight of the bike no matter what right? (assumption). The other thing to note is I based it purely based on a horizontal flat surface of the road; where in a banked turn you definitely can go faster. So even with the lateral g-force how much of it is affecting it in the vertical direction to affect the normal force perpendicular to the road surface to the tire; how much is the vertical component. Assuming CG is same is the lateral g-force horizontal and parallel to the ground? But yes the friction lost should/could be negligible even on a flat surface. Regardless like I said you are correct I shouldn't have mentioned the friction part; as the centripetal force is what really causes the loss of friction with the velocity component being squared which is why we go slow (even though amount of friction may not have changed?).
  39. 1 point
    Not actually having ridden in the dirt, I can only speculate. With low traction offered on gravel, less weight is moved up front during braking, so more braking can - and must be - handled by the rear brake/wheel. I reckon they also back the bike in severely quite often, with a locked wheel, to turn quicker and very low speed. Finally, they use the brake as well as engine/wheel acceleration to control the balance of the bike mid-flight.
  40. 1 point
    I think the simplest solution would be for you to go ride and try it and see what actual results you get. It shouldn't take a lot of muscle effort to just sit on the bike, but when braking hard or trying to hang off it will take more. During the braking and hanging off times, try doing it with abs slack, and then try tightening your whole core and see what gives you better support and less stress and muscle fatigue on your back. If you want to get really serious about getting strong, flexible, and comfortable on the bike, get into yoga. I coached a guy recently on body position - he was 2-3x older than everyone else in the group with him and way more flexible and strong on the bike. I mentioned it and he said he started doing yoga and was astonished at the difference it made. I've heard this enough times to take it quite seriously, it definitely seems to work.
  41. 1 point
    I've been looking for this thread earlier today and couldn't find it. I know that my skills have improved because my attention was not stuck on my SRs firing off, checking my fun. I commuted to work yesterday then back home, then to class. I'd forgotten that I had on my dark shield as I stopped by the motorcycle shop to check on my wife's bike, and I stayed too long. I had to race the remaining daylight. It was the most fun I've had in a long time. I was smoother, faster and more in control of putting the bike exactly where I wanted and we were a better meld.
  42. 1 point
    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.
  43. 1 point
    I think this is where you see a big difference between the big bikes and small bikes - on the smaller displacement machines it is all about carrying corner speed, you see a much higher entry speed and the rider carrying a lot more speed in the corner - that smoother, flowing style. I also think club racers on 600/1000cc bikes are inundated with advice to "brake until the apex", so they end up trying to apply that in practically every corner and end up giving up way too much corner speed as a result. Then they feel like they have to get on the gas really hard to try to make it up, or to stay ahead of the guy they see coming up behind or around them. You don't hear a lot of "brake until the apex" advice if you are on a 250. I am saying "they" because I have seen plenty of others do it, but I certainly have done the same thing myself! It "feels" faster on the 1000cc bike to brake really hard, and gas it really hard, and even with all the training I have I tend to fall into that trap if I am "trying" to go as fast as I can. I got towed around recently by a top pro rider and guess what? Higher entry speeds, higher corner speed, and he was gentler on both the brakes and throttle than I was. Sigh, it was a reminder that just getting on the gas harder is not the solution.
  44. 1 point
    I feel like I accomplished something by finishing that story. (if you read the story you'd understand- LoL)
  45. 1 point
    OK. So... if you don't have a point picked out for an apex AND haven't looked in toward the apex, you don't really have any info about where you want the bike to go - so how confident will your quickturn be? This is a good review exercise for forum members, what is the timing on 2-step? When should you spot your turn point and when should you look in to the apex? Spot your turn point as soon as possible because it controls many decisions (where to brake, when to downshift, etc.). Without reference points, there is no turn point. No bueno. The time to look at your apex is just before you reach the turn point. A rider requires a turn point to have the attention left to spend on his next reference point, the apex. If a rider is confident on his/her location (turn point/reference point), the rider is "free" to look at the apex just before flicking the machine into the turn. Like in real estate, location, location, location is of primary importance. You must have RPs to get your through the turns; you can relax on the straights.
  46. 1 point
    I love to survey riders. What do they want from riding; how would they like it to feel; how would they like it to look? Want is consistently answered with smoother, faster and increased confidence. Feel runs the gamut through smooth, solid, stable and predictable. Look also ranks smooth above all; followed by fast, which translates into hanging off, knee on the floor. That is the dream. Riders of all classes of bikes, once astride a sportcycle and at a racetrack, feel left out and are often crestfallen until that magic moment finally comes; the krchchshh of getting a knee down. If only the photographer had been in that corner…that lap. In the evolution of our species we’ve gone from knuckle dragging to knee dragging. An alluring picture of what they imagine or wish to look like can hamstring anyone. These are most often gleaned from dramatic magazine or TV shots stored in their library of mental images and riders envision themselves in these poses as an end unto itself in their quest to improve personal riding prowess. Going for the look without some understanding of its utilitarian underpinnings is, in a word, wrong. In the evolution of the art of cornering the look of it has had four complete phases--so far. The neat, tidy knees to tank, stretched out on the bike style of the 19-teens through the ‘60s was handed down, eye to muscle memory, as the path of least resistance; you could even say “the natural style” of riding. Phase two: Mike Hailwood let his inside knee come off the tank in the 1960’s and practically created a stock market panic in the riding style etiquette market, it was a huge departure from tradition. Paul Smart, Barry Sheene and others followed. Then, Jarno Saarinen actually moved his butt off the seat a bit which was emulated by many. The fourth phase is credited to and was pioneered by our own Kenny Roberts Sr’s knee down style hangoff in the 1970’s. Initially this earth-shattering look was quite personal to the rider, each having his own iteration of the new form. Cal Raybourn and Kel Carruthers were halfway guys, still clinging a bit to phase two. Some others had lots of bum off, some with lots of leg and knee off, some rotated around the tank a la Mick Doohan. A few went head and body way down and on the inside of the tank, Randy Mamola style, some hung-off but remained sitting more upright like Kevin Schwantz. The torso positions for our other 500cc world champs of the era; Eddie Lawson, Freddie Spencer and Wayne Rainey were half way between, on the tank but not inside it. Most of the originals also tended to ride forward on the tank and finally, everyone was stationary in their hung-off position once in the corner. The neat part of that era, with all these splinter groups, was that a fan could have instant recognition of the individual’s style and look. Not so today, phase five is upon us. Conceptually, hanging off couldn’t be simpler. Lower the combined Center of Gravity (CG) of the bike/rider combination and you go through the same corner at the same speed, on the same line with less lean angle: all in all, a brilliantly utilitarian racer’s tool with huge residual benefits; chief among them being an accurate, on-board gauge for lean angle and true to most evolutionary progressions, function now rules the new look and style of road racers. Take a look; riders are low and inside of their bikes. More and more we see them perfectly in line with the machine, not twisted or rotated in the saddle. The bum off/body twisted back across the top of the bike positioning, which many phase four riders had been doing, was and still is an interesting piece of self-deception. With their torso mass on the higher side of the bike, it not only neutralizes the mass of the hips being off the bike but actually is a negative, raising the combined bike and rider C G--defeating the technique’s main function and purpose. Other notable changes include not being so stretched out as before but not always with the family jewels on the tank either. The one new variable in phase five riders is coming further off the bike mid-corner to exit. You’ll see it on the bum-cam position next time you watch riders like Val Rossi in Moto GP. That and the fore/aft in the saddle differences appear to be the only options available to our phase five evolution racers. We have five choices now in how we can look and relate to our bikes. If you keep your eye on the style’s function and do some limbering exercises all the benefits of phase five will become apparent as you become comfortable with it. Is it easy? My experience says it is not a natural style at all and riders are hard pressed to assume the new form. If it is your desire to do it I suggest taking your time and step by step, experimenting with each of the stages through which it has evolved. Good luck. ˆ Keith Code, 2007.
  47. 1 point
    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!!!!!
  48. 1 point
    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.
  49. 1 point
    I love this article, it completely captures the difference between a wonderful ride and a tedious, frightening, or disappointing ride. For me, the best ride, the perfect ride, is when I can find that joyous excitement, the special thrill of feeling the bike skimming over the pavement, and seeing the track flowing swiftly by. There is a disassociation from concerns about "how I'm riding" or who is behind me or what I should change, it's all sensation and it seems like the controlling of the bike becomes nearly effortless. For me, a really terrific fast turn feels like sledding down a steep snowbank, or swinging too high on the swingset; I've committed to the turn and now I'm just enjoying the ride, and seeing how fast I can go! There's a certain death-defying feeling to it, which makes it thrilling; and a certain perfection, when it all comes together exactly right. When I can capture that feeling, I stop being a bundle of worries, and thoughts, and wasted motions, and start really having a ride.
  50. 1 point
    As I have stated in the R1 forum lengthy and technical discussion on CS vs BS, additional evidence that gyroscopic precession is inconsequential to steering a motorcycle can be found in the common experience that lighter wheels/tires (which have a lesser polar moment of inertia) are easier to steer, despite the fact that by virtue of their decreased rotational mass and polar moment of inertia, they exert a lesser gyroscopic precession force on the vertical axis to lean the bike over.
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