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Hotfoot

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Everything posted by Hotfoot

  1. Points 1-4 is covered specifically and in detail in Twist of the Wrist II in Chapter 10: Rider Input, Riding and Sliding. There is a good diagram and description of what the front wheel and the bars will do in a slide, which way they will turn. It also tells you exactly what happens if the rider tries to turn the bars or gives the opposite input. It is better read there than answered here, since there is a thorough explanation, diagram and photo. In regards to your second set of questions - yes the slide would be in the same direction - the angular momentum of the bike would send the rear wheel to the outside of the curve. If the bike is nearly vertical, you are not on a circular trajectory anymore. The front wheel will still turn the same direction as your scenarios above (as described in TOTW II), but if you are mostly upright it wouldn't be much, because at that point you are going mostly straight. The pick up will improve your traction by getting the bike more upright. However it is always possible to upset the chassis or suspension with an overly aggressive bar input; it would seem very unlikely especially in good traction conditions for it to actually cause a crash but possibly if you seriously overloaded the front suspension with a really heavy bar input, way oversteered it, OR unintentionally braced with your other arm thereby loading BOTH bars and creating a rigid transfer point between the bars and your body (and thus the rest of the bike) you could cause a wobble or an unwanted bounce from the front suspension or tire. If a rider tries to do a really aggressive, fast pick up right around the moment where he/she is trying to begin their roll-on, how likely is that the roll on itself will be smooth and progressive? If the roll-on is, as a result, too abrupt, what could happen to the rear tire traction?
  2. The guy on the Ducati would really benefit from CSS Level 3, check out his transitions across the bike (and how the bike reacts) and his lock on, how secure does his lower body look?
  3. Here's some hints on these rear tires slides: LISTEN to the engine, how smooth is the throttle application when leaned over? Watch the rider on the R1s throttle hand - what does he do when the rear tire starts to slide? What control could a rider be using that could cause the rear tire to slide on the entry? What could a rider do on the corner exit that would cause the rear tire to be under much greater load than the front? I'd also ask - especially in the case of the black guy on the black bike near the beginning of the video - what is the condition of the tires, and are they adequately warmed up?
  4. Those are massive changes in lap times, and sounds like you are doing it with a plan, making changes gradually so as not to fire off the SRs, and really using the drills and techniques from the school, great job! Glad to hear you are getting such excellent results, well done!
  5. If so, I stand corrected, what lean angle are we talking about?
  6. There is a section in Ch 13 called "Front End Duties" that talks about how the front end still contributes, and also addresses getting on the gas too early. Notice that when it says in TOTWII that the bike will maintain its lean angle even with the front wheel off the ground, it does NOT say that you have maximum corner speed/traction in that situation (you don't), and the section referenced above on front end duties talks about that. While you do see racers commonly wheelie out of corners, you don't see them wheelie in the middle of the corner at max lean angle, because you just can't load the rear that much at max speed and lean, it would lose traction before it would wheelie. Another thing to note is that while acceleration alone can and does cause wheelies, another thing that can contribute is the release (rebound) of the front suspension as the bike is coming out of the corner, and that may be some of what you are seeing in racing. Some riders - not going to name any names here - when launching a big show-off wheelie, use a sharp suspension compression/rebound to help loft the front.
  7. If you are looking at dates that are closer but are sold out, call the office and ask to be put on the waiting list, sometimes spots open up.
  8. What is the logic behind feeling like you'd need to stand the bike up before leaning it again, or where did the idea come from? Are you talking about a turn where you would need to brake hard before the second steering input?
  9. Glad to hear you are comfortable with what the bike is doing and have a better understanding of it, especially since you were able to use the freed-up attention to improve your focus on the drive out of the corner, that is a great win. So, what is it about those three corners that would get you 4-5 seconds off your lap time? Are they turns leading onto straights, or very long, fast turns...? Since you have data and GPS I'm curious.
  10. 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/
  11. Have a look at Twist of the Wrist II, Chapter 13 "Steer for the Rear". The fourth paragraph, in particular, may shed some light on the situation.
  12. Welcome. Share some race stories! Clubman is a fun class, what are you riding?
  13. Wow, great post and great win on getting NINE seconds, that's fantastic. I really like your description of the difference between level 3 and level 4.
  14. Black + gray carries a heavy duty hanger for leathers: http://www.blackandgray.com/products/hangers.html
  15. How old is your brother? What general type of bike - road bike or dirt bike? Does he have any riding experience? Are you in the USA?
  16. I finally bit the bullet and got some Held Phantom II gloves. Haven't had the chance to ride in them yet but they sure are beautifully made, the fit well and the quality and protection seem very impressive and they are comfortable. I'm sure they'll need a little break-in but I look forward to trying them out on the track. I have Alpinestars, too, and I've been very happy with them - my only reason for trying something else is that they changed their sizing and now I am apparently between sizes so they don't fit as well as prior models I've had. I'm excited to try out the Held gloves but they are in a different price category - for features, protection, value and availability it's honestly really hard to beat the Alpinestars.
  17. Ok first of all this is TOTALLY awesome that you have this data to post! The datalogger is fantastic, and I'm glad to see you using it, what a great application. That second chart is terrific, lots of information there. At first glance at the second chart things look pretty even from one side to the other, your lean angle is not drastically different on rights versus lefts, but on closer examination the throttle position versus lean angle does look somewhat different - that top red line showing around 75% throttle at 40+% lean angle and some of the yellow and orange at 45-50% are more apparent on rights than lefts, and the slip rate seems, in general, a little higher on the rights but not much (looks like more data points in the >10% range?)... and maybe the characteristics of the corners on that track are what is causing those differences. I think I see the problem - the Michelins are not "adapting" sufficiently to your situation. Do you know if the tire damage is more within the first few laps or sessions or at the beginning of the day versus later? That might help determine if it is cold or hot tear, it sort of looks like hot tear to me (the tears look wider and shallower than I'd expect to see for cold tear) but for sure I am not an expert. But the fact that a 2 psi pressure increase seemed to improve the situation would support that as well - if you have a chance next time to check tire temperature and pressure before and after riding (straight off warmers versus coming off the track) that should help tell you whether it is hot or cold tear, that article above has some specifics of what temp/pressure rise to look for, and/or the tire rep should be able to tell you what is optimum operating temperature/pressure for that tire, to compare to what you are actually getting. If it were me I'd check the alignment on that rear wheel - not sure whether that would or could have anything to do with this type of uneven tire wear but it's a really easy thing to check, and a good idea to do anyway. Then, if the tire pressure and compound seem correct for the track (per the tire rep), I'd next try softening the rear suspension and see if that helps, since that could contribute to hot tearing by making the tire work too hard because the suspension is not compliant enough. Also check the spring rate recommended for your weight and see if you are within range, if the rear spring is way too stiff for your weight that could be contributing to the problem. Since you have good photos AND access to the wealth of information from your datalogger, you could try reaching out to Dave Moss to see what he thinks on the suspension side, I think he does analysis like that and it would probably be refreshing to him to have all that data available to work with. Dataloggers are such an amazing tool!!
  18. I'm not a tire or suspension expert by any stretch, but here are my thoughts: 1) Since it only is happening on one side (and you are riding multiple tracks) that would imply an issue with riding style - unless the tracks are all very right-handed - less likely that a suspension or setup problem would only affect one side. A rider that drives much harder while leaned over farther on right handers might experience different tire wear on that side, though, does your lean angle or body position look significantly different from one side to the other in photos? 2) I'm not a suspension expert but this does look like tearing, is this is multi-compound tire, and is the compound on that part of the tire super soft? Personally I have only seen that kind of wear when the tire was too soft for the for the track surface and/or if temps were out of range (hot tear or cold tear). You might try asking a tire vendor what compound they use on the tracks you run - especially since you didn't have the issue with the Q3s, could be the tire is just not appropriate for the surface, or that it has a super-soft compound at the outside edges and THAT is too soft for the surface. 3) The width of the worn area looks even to me, doesn't show the wave or wider/thinner areas that you might expect to see if suspension was the issue. Do you run warmers? How much does the tire pressure change from coming fresh off the warmers to coming off the track after riding? What sort of outside temps were you riding in, and do you have to sit for long between coming off the warmers to riding at speed on the track? Dave Moss's various websites and videos are a great source of info, here is one that might be helpful:
  19. 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. >>
  20. One day I was putting a whole series of riders on a bike to work on body position (part of the level 2 off track exercise) and one guy, who was in his 60s, was strikingly more flexible on the bike than everyone else and was able to get into a very hung-off position that was really stable and strong. I commented on his flexibility and he said he had been doing yoga and it really helped. I certainly agreed with him - he was flexible and strong for any age, let alone for someone in their sixties. I was quite impressed. The flexibility in his hips, legs and ankles (compared to everyone else) was the most noticeable when seeing him on the bike.
  21. When you sit on the bike on a stand, and get in your normal hanging off positon (assuming you hang off for corners), can you let go of the bars and still feel secure? Is it easier on one side than the other?
  22. We've towed a variety of different trailers and as you stated above, there is room to get it a little "wrong". As long as you are not extreme in loading the very back or very front unevenly you shouldn't have much trouble, so putting the bike(s) over the axles ought to handle it without having to get it right within a couple of inches.AS an example, think of toyhaulers - they have a huge amount of trailer weight in tanks for fresh water, gray water, holding tank, and large fuel tanks (on board fuel station) and the loads very considerably between empty and full and in between, but the trailer hauls solidly regardless (well, ours have, anyway) of which tanks are full or empty. Those tanks are placed near the axles, of course. Personally the only time I've had trouble was when the vehicle hitch was too high so the trailer was not level (it was high in front which made it want to wag) or if ALL the weight was in the back of the trailer, which I accomplished once by loading a small trailer (14 foot) with a riding mower and nothing else, and putting the mower in the very back. That didn't feel good to tow, but I hadn't been paying attention to how I loaded it since I was only going down the street. I wouldn't do it that way again.
  23. Thanks for posting this, so glad you had such a good result AND saw it translate to your street riding, it's cool that you were able to go ride a good fun road so soon after school and find out what had changed in your riding. Look forward to seeing you back again!
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