Jump to content

Leaderboard


Popular Content

Showing content with the highest reputation since 05/22/2017 in all areas

  1. 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.
  2. 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.
  3. 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?
  4. 3 points
    Cool story. Read this: https://www.scientificamerican.com/article/the-bicycle-problem-that-nearly-broke-mathematics/#
  5. 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?
  6. 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.
  7. 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.
  8. 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.
  9. 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.
  10. 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.
  11. 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.
  12. 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.
  13. 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...
  14. 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.
  15. 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.
  16. 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.
  17. 2 points
    Riding a curved on-ramp at the speed limit with a cop behind you.
  18. 2 points
    it's all relative. Maintenance throttle in turn 8 at willow Springs on a SV650 is 100%
  19. 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.
  20. 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.
  21. 2 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.
  22. 2 points
    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.
  23. 1 point
    Thanks for the responses! I would say the majority of the hard acceleration corners at MO and Grattan (Clockwise) are right handers. I attached a data logger plot of MO - the highest spin at high throttle are the keyhole exit (turn 10 in the plot) and the thunder valley entrance (turn 4 in the plot). I was surprised to see that the logger shows spin through the back straight kink, and this is also on the right side of the tire. I haven't noticed a different body position from one side to the other, however, I do think I feel more confident with right turns - a lot more knee puck wear on that side! I am using the Michelin Power Slick Evo. The Michelin reps at the track have some buzzwords about it (Two Compound Technology (2CT) and Adaptive Technology (ACT)), the gist of which seems to be that there is only one compound and it's supposed to adapt to conditions. I did try a Pirelli Diablo SC2, which I think is their harder compound, and I had a similar wear problem - tearing on the right side. I do use warmers, and I set the tire pressure coming off the warmers; I haven't looked at what the pressure is coming off the track. The outside temp has varied from low 70's to mid 80's. At most, there is a 5 minute wait before coming off the warmers and heading out to the track, and I put the warmers back on within 5 minutes of getting off the track. The Michelin rep told me to run 24psi hot off the warmers, so that is what I've been running. When I asked a riding coach about the tearing at MO, he suggested I run 2 more psi, so I tried running 26psi - this seemed to help a bit. He also suggested I flip the tire when I saw signs of tearing, so I also did that. I did read the forum article here about tearing, but that was afterwards (:>).
  24. 1 point
    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.
  25. 1 point
    https://www.redbull.com/int-en/motogp-repsol-honda-team-f1-red-bull-racing-2015
×