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  1. Lots of good data from some of you and especially Hotfoot’s info. Here’s just a bit more on the subject of Pivot Steering. May be repetitive of some data already written but look it over an do the experiment at the end for fun. My statement in Twist II about getting your weight closer to the center of mass or center of gravity by weighting the pegs rather than the seat and any implication that it alters the center of mass (COM) or center of gravity (COG) was, or helps in any way is, for lack of a better words, junk, incorrect, wrong. Weight in the seat or on the pegs does not change
    5 points
  2. This is a very broad question. The answer will depend on a variety of factors about the corner: radius (and whether it is increasing, decreasing, or staying the same), camber, surface (grip, bumps, etc.) so I am not sure what sort of answer you are hoping we can provide. If the radius of the corner is increasing, and the camber is either unchanging or getting more favorable, you should be able to accelerate through the corner, however if the radius is decreasing and/or the surface is going off-camber, you may have to be slower later in the corner instead of faster. A corner with a crest i
    4 points
  3. Whew, this thread has gone all over creation and back since the original posted question, and the OP seems to have checked out. So, I'm going to jump in here. I am a CSS coach. First let me note that Yakaru is a very competent rider, fast, has come to many schools, and is very knowledgeable on the material. Now, on to some of the info that is in question. 1) When a rider is in a corner, if the throttle is APRUPTLY shut off, the bike will INITIALLY stand up a bit and run wide. Sudden loading of the front tire creates drag on the inside of the contact patch which tries to turn the
    4 points
  4. Keith asked me to add a little more info about grip: The point on max grip is another many faceted process. Due to the slip angle tires never do have 100% mechanical grip, they actually are sliding. That is a prophylactic process as it cleans the spent rubber off the tire's surface but is ALWAYS happening, in every corner. It's sometimes overlooked in the traction arguments. In the end it's more to less, less to more SLIDE rather than more to less, less to more traction. Maybe that's just another way of looking at the same issue.
    4 points
  5. This is a common enough question that lately Keith has put a new focus on the no-brakes drill with Level 4 students, having them re-do the drill to help increase their awareness of how much speed gets "scrubbed off" in a turn, and to make sure that concept is understood. There are, in fact, multiple Level 4 drills designed to increase the rider's awareness of this, and help the rider determine where, EXACTLY, one should have their entry speed set for a given corner. Dylan actually does cover this topic pretty thoroughly in the very first lecture in Level 1, Throttle Control, pointing out that
    4 points
  6. Great to see the responses on this. Some years ago a coach missed T-boning a car at an intersection. This boulevard had a median, and tall curbing on the street-side edges. The car pulled across the median and then stopped in his lane. He steered quickly right, but had to also steer it back left (or hit that tall curbing). Both the visual skill (of not target fixing) and able to turn it quickly, are practiced skills, saved his bacon that day. It's a recommendation for simply getting onto a track now and again. Practicing riding technique in a controlled environment is ben
    3 points
  7. Hanging off moves the combined center of gravity of bike and rider more to the inside which allows the bike itself to be leaned over less. With the bike more upright, the suspension works much more efficiently which improves traction by keeping more of the tire in contact with the road.
    3 points
  8. Your collection of data and research shows you are barking up the right trees. Here's some more data regarding tires: Per the Dunlop engineers tires grip in 4 ways: 1) Adhesion--the temporary chemical bond between the tire and surface. 2) Keying--the tire deforming and filling in all the nooks and crannies of the asphalt or squishing into the depressions. 3) Abrasion--the tire tearing from itself or wearing away. 4) Hysteresis--the energy storage and return by the rubber and partial conversion to heat. The first two can be looked at as static properties and the la
    3 points
  9. It sounds to me as though you might not be taking into account how suspension affects tire grip. Are you, for example, assuming a completely rigid connection between the wheel and motorcycle, with no suspension action and a non-deformable tire? Are you assuming that the grip of tire to pavement is constant, and is at the theoretical maximum friction of rubber to asphalt? There is more grip available when the bike is upright because the suspension is more effective at keeping the tire consistently in contact with the pavement. There is a theoretical maximum friction that you can calculate but i
    3 points
  10. I do not understand this statement, can you restate it or explain it more? If I understand your question about how to exit a corner, you are talking about coming out of the corner onto a straight(er) part of track, and you are asking how to change the arc to put the bike in a straighter line, is that right? If so, then the answer is yes, you would counter steer to bring up the bike. The momentary instability caused by the countersteering effort is overcome right away by the increased grip afforded by getting the bike more upright (primarily due to your suspension being able to work
    3 points
  11. Interesting topic. Three things that came to mind while reading through the posts: 1. Many moons ago, Roberts sr had trouble going fast enough around Suzuka. Instead of continue circulating, he went back to the hotel and had a think. A few hours later he returned to the track and said he had found 2 seconds. Hei proved it by going 2 seconds faster. 2. Darren Binder, Moto3, says he has no braking points, he brakes when those around him does. He's fast, but cause a lot of havoc and crash frequently. 3. Rossi, and others, often try a fully new and untested setup before races when
    3 points
  12. Practice till you can't get it wrong, I'd just heard this in another arena (pistol shooting), but like the idea!
    3 points
  13. They have full gear, so the same undersuit suggestion applies to women as men. as for school vs camp: I get a lot more from the camps, personally, and favor them for the increased time per day on the track to refine things. But it’s something I can see others wanting more “processing time” for the lessons or not physically prepared for two full days of riding having the opposite opinion. In the end though I’d say it’s probably not a drastic difference either way — both will be effective so pick the one that you think sounds more appealing or fits your schedule better.
    2 points
  14. I was so happy to find out, today, that A Twist of the Wrist II is available on Amazon Prime Video now! You can watch it instantly, here is a link to it on Amazon Video (or you can just put A Twist of the Wrist in the search box) : https://www.amazon.com/gp/video/detail/B089ZNVBW9/ref=atv_dp_share_cu_r And since we're talking about the movie, what was your favorite part? I can't wait to hear what y'all liked best. My favorite part is the CG animation and explanation of why using the front brake in a corner tends to make the bike stand up, it was BY FAR the clearest explanation I
    2 points
  15. Faffi adds an excellent point; a little stiffness in the arms (a common in-too-fast survival reaction) will restrict bar movement, add load to the front, and potentially add some countersteering input that leans the bike over farther which can VERY easily overload a front tire that is already near the traction limit. Some braking references in Twist II that might help you (the OP) on info about leaned-over braking: Ch 24 Braking sections "Efficient Braking", "In-turn Brakes", "Crash Statistics", and "Brave or Smart". Also the chapters in Section II on "Rider Input" and Section III on
    2 points
  16. I have the Kindle edition, here is a link for Twist II for Kindle: https://www.amazon.com/Twist-Wrist-II-High-Performance-Motorcycle-ebook/dp/B00F8IN5K6 and here is a link for A Twist of the Wrist (Twist I), it is available on Kindle also: https://www.amazon.com/Twist-Wrist-Motorcycle-Racers-Handbook-ebook/dp/B00BNFIU08/ref=tmm_kin_swatch_0?_encoding=UTF8&qid=1593622442&sr=1-2 I love having these, because I can search for a word of phrase electronically to go right to the info I want. And it's great to be able to pull up the books on my iPhone Kindle App, at the tra
    2 points
  17. Yes, riding the NO B/S Bike with Josh Galster behind me...outright terrifying. Let's the stage: Josh was a pretty solid AMA Pro, racing 600 Supersport at the time, good rider. We were on the NO B/S Bike, and came pretty close to the camera car (seemed way closer on the bike than it does in the video). At what seemed like the last possible moment Josh would reach down with his thumb and steer the bike away from the car. What you might not be able to see is how hard I was pressing on the NO B/S bars--surprised they didn't bend. Veins popping out of my neck, trying to steer the bike (w
    2 points
  18. That movie changed my life. I had been riding (commuting) about 5 or 6 months when I figured I was ready to ride some twisty roads. So I went out and scared myself pretty bad. The bike wouldn't turn, I was crossing the yellow repeatedly, my wrists hurt from my death grip on the bars, etc. Every corner was terrifying; a "mild panic" as they say in the movie. It was a bad day. Then I found TOTW2 and I felt like Keith had just watched me ride and was going over my mistakes, one by one. The entire movie was a series of "ah-ha!" moments. Everything was explained so well. Now I've done a bunch of sc
    2 points
  19. Looks like good news:
    2 points
  20. A lot of this has to do with the specifics of the corner but for the general approach: - You usually want to shift the weight balance forward to change direction. Depending on the bike and corner this can vary from a pause in the roll on, a partial roll off, a complete roll off (preferably with intent, not just chopping the throttle), or application of the brakes. - Once on line you roll back on, moving the weight back, stabilizing the bike. Again depending on the corner and bike the nature of this can vary. There's a corner at one of my local tracks which, on a 250cc bike, I do
    2 points
  21. Sorry to hear about the down. I think Apollo has the core of it, and if your lecturer didn't say to obviously use the brakes if you needed then that does seem to be an oversight. I'll put a clip in at the end from the Superbike UK's level 1 presentation -- should jump to 18:16 -- which is the clearest explanation of 'how' and 'why' to do the drill (including using the brakes if you must). In my experience, the no-brake drill is best approached in a stepwise manner and helps tune entry speed and understanding of slowing from things other than the brakes (tire drag, lean angle, engine
    2 points
  22. I'm pretty happy. Got to grow my trophy case a bit.
    2 points
  23. Being a mediocre rider with a history of more brawn than brains, I have had to stand the bike up to slow down before continuing at a reduced pace countless times. Sometimes from running out of cornering clearance, sometimes just running out of courage. I have never planned for it or practiced it, it's just a result of my SR.
    2 points
  24. I'll pass on that feedback, it might make sense to resurrect that forum section. From participating in some other forums I DO understand the questions/concerns that arise when you don't know the sources of the information you get. This particular thread covered a whole lot of ground in a short amount of time, and got confusing, but from what I saw most of what was said was correct in one way or another, just incomplete or stated in a way that was not absolutely clear. Perfect example is the question of what happens when you roll off the throttle in a turn - one person said the bike stands
    2 points
  25. I think we need to clarify whether we are talking about "weighting" the outside peg or talking about PRESSING on the peg. Pressing down on the peg with your muscles to force you knee up into/against the tank can improve your lock on and that is a nice benefit. Using the outside lower leg as a strength base for pivot steering is not weighting the peg, it is using the peg as the most stable pivot point. (Just standing on the peg doesn't work for pivot steering because that is not the same as locking your lower leg to the bike.) If a rider senses an improvement in the bike's handli
    2 points
  26. Personally, I prefer a softer carcass and a more rounded profile for the tire. That's partly because I am a smaller rider and most bike's suspensions are too stiff for me anyway so the softer tire helps absorb some of that, but it is also because I like to feel the tire react - I like to feel the tire "set" in the corner, and feel it compress under acceleration. I do not like to feel rigidity or vibrations, or feel like the tire isn't reacting or won't compress, that sort of feedback tends to make me feel like the tire is cold or has too much air pressure and won't have adequate grip, so I am
    2 points
  27. We are shooting for Barber, which is May 23-29. It's mostly booked up but there are about 10% seats available.
    2 points
  28. We made it out, about 2 hours north of LA in the desert. Had a great time, daughter loved it--asking about going again this coming weekend!
    2 points
  29. It definitely can be done (sliding an S1000rr in a controlled fashion) and you can watch high level racing and see it happen. The school also has an off-track tool called the Slide Bike that can be used by more advanced riders to find our what it feels like to slide the rear tire. (And, for that matter, there is the Brake Bike that can be used to find out how it feels to slide and recover the front, in a straight line on the brakes.) One thing to consider is that the tires are ALWAYS sliding, to some degree, it is a built in part of how they work. In any corner the tires are always scrubb
    2 points
  30. The brain is not typically wired to be bothered with words like "don't" and for most will only react to "fixate". If your kid has ice cream running down the chin and you tell the kid "do not look down", the child will definitely look down. If you instead say "look up", you can wipe the chin before the kid ruin the shirt.
    2 points
  31. I love it when topics get resurrected, and especially when I have just discovered the technique, literally yesterday...it forces me to relate my newfound exuberance not only to the "what" but also the "why." I am not a proud author and I am seriously interested in all responders. Why? Because if what I know to be true as outlined below proves false - I need to know ASAP. First, kudos to the CSS Coaches who asked the poignant question and provided the illustrative example: i.e. Cobie's 'stirring the pot' getting the topic back on track, "Does it matter which peg is weighted?" and then Ho
    2 points
  32. I have been told that weighting, or rather pressing down on the outside peg allows you to corner faster and safer, as it encourages you to put your head and shoulder weight, and not your butt, inside the turn (aka: kissing the mirrors), which requires less lean angle in a given turn/curve. (Your upper body weight leaning into the turn replaces some of the bikes weight it would use in the lean, requiring less lean angle on the bike) Ive taken turns where it seems the bike stays almost upright, and I'm able to hug the inside line nicely in the apex of long curves. It helps as well as it puts an
    2 points
  33. Thinking takes a bit of time. While riding (or other high speed potentially lethal activities), that's too slow. A few different pieces of this, but the first one is I actually applaud the guys that take the time to come to this forum, and work through some of the pieces of riding. There is a technology to riding. But for one to be able to look at the technology of riding, has to be willing to think it over, work through the pieces, do some study. That is for sure the first step. I'd have to say that this is more a thinking man's forum than some others. Like I said, got a few parts t
    2 points
  34. The answer to the question is: from turn-in, off throttle, not trailing the brakes, the bike will slow at the rate of between 3mph to 8mph/sec. Lots of variables of course but that's the quick answer.
    2 points
  35. You are correct, but only if such motorcycle is neutral steering-wise. As you know, many bikes have a natural tendency to either understeer or oversteer (if the rider releases the handlebar while the bike is leaned on a curve). Those tendencies depend mainly on geometry and profile of tires. The front contact patch of an understeering bike will "feel" less lateral force when coming out of a lean/corner as it had been forced to over-steer during the curve. In the steady conditions that you have described (while keeping zero angular input on the steering), the sliding force on each conta
    2 points
  36. Here are some places to look in Twist II for info on downhill turns: Chapter Two, Throttle Control, the section called Survival Training. Chapter Four, the section called "Other Exceptions" near the end of the chapter. Twist I also has some info: Chapter 1, The Road You Ride, the section Uphill, Downhill, and Crested Turns
    2 points
  37. I love this topic. I too am focusing on my turning ability, specifically Quick Turning. There’s an article where Keith says that learning to QT solves all of the SRs. I’m striving to become a disciple of that.
    2 points
  38. Great questions. I was working hard at being a good copycat. I didn't brake at all, and I stuck to his fender and turned where he did. He was super-smooth and got the work done with speed and grace. I assume I was not as graceful, and I was probably off the throttle too soon, and not on again fast enough, because I was having some emotions at the time. As stated, I thought this was a mistake..but it was brilliant. Hard turning. I ski. To go down a steep face, you turn hard and often to keep your speed in check. Miss a few turns, and you have to slalom, fail to dig in, and you
    2 points
  39. That's awesome, the pat on the back was great lol
    2 points
  40. What would you say is the skill/thought process/etc. you get the biggest benefit from focusing on -- either for training/practice or in/around a race?
    2 points
  41. Good summary Hotfoot. I'd always thought of WSB like NASCAR, and MotoGP like F-1
    2 points
  42. I recognize that I’m almost exactly 3 years late to this party, but the past three weeks I’ve been using the forum search function and scrolling through pages of posts on a tire heat/traction research assignment from Cobie, and this thread is definitely the best I’ve come across yet. Cobie, you’ve done a great job of engaging and drawing participants out; there’s been a symbiotic contribution-response at almost every point along the way. The only thing I can add is an over-simplification of the topic, but based on the posts, I believe we all understand it: ’Train until you get i
    2 points
  43. Here is a good summary of the difference between MotoGP and WSBK: https://www.redbull.com/gb-en/superbike-vs-motogp-differences One major difference is WSBK machines are based on production motorcycles and MotoGP bikes are purpose built race machines or prototypes. MotoAmerica is the organization that promotes the premier North American racing series, and part of its purpose is to develop riders from North America to compete on the world level in WSBK and AMA, and uses production motorcycles. MotoAmerica is sanctioned by AMA and FIM. What we used to call "AMA racing" is now Moto
    2 points
  44. If you turn off the "off-track aid in the options, you well definitely fall on the grass lol, trust me lol
    2 points
  45. It would be a rare 180 degree turn where you could roll on the gas as soon as you have your lean angle set (at the beginning of the turn) and be able to roll on continuously for the whole rest of the turn. If the turn was large, and U shaped (as an example) you would most often have to roll off (or at least go flat) on the gas in the middle of the turn, more or less treating it as TWO turns, the first part with one turn point and apex and the second part with its own turn point and apex. Depending on the shape of the turn, you may or may not need to make another steering input to change your l
    2 points
  46. I just paid to attend the 2 days training class at Barber on May 27/28 of 2020. I have been riding for many years and still have to ride with confidence coming to a corner. I am turning 60 this year and this course is my gift to myself. Looking forward to learning from everyone and I bring no ego to bruise. I have read the TOTW II book and watched multiple videos and can't wait to make it out to Barber. Hopefully, I will attend the Las Vegas track later in the year for Levels 3/4. See ya'll soon.
    1 point
  47. Sorry all, I was out of town on vacation, and just let this drop! I'll get with Rocco in the next day, get answers! CF
    1 point
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