Jump to content


  • Content Count

  • Joined

  • Last visited

Community Reputation

0 Neutral

About matt17

  • Rank
    Cornering Apprentice

Profile Information

  • Gender

Previous Fields

  • Have you attended a California Superbike School school?
  1. +1 We aren't considering that really high-speed turns may not be limited by lat acceleration, think e.g. of Turn 1 at Laguna Seca.
  2. Matt, I should mention that I made a typing error in my example above, having stated the dimensions for the second turn were the same as the first. They are not and are corrected in that post. I followed your math, but don't see that it supports your quote above, as stated. Taken literally, we could simplify the example to remove the turn and say we're riding the same 1,000 feet of straight road. If we make a pair of passes, one at 50 and the other at 51 mph, the difference in the time it takes to cover the 1,000 feet is .27 seconds. If we make a pair of passes at 100 and 101 mph, the elapsed time difference is .07 seconds. For your statement to be true, the distance covered must be proportionally larger. Your math allows for this, but the opening statement doesn't seem to. That statement is only true in the context of the situation you presented, a constant radius turn at a defined speed and lat acceleration. These two values determine the radius and length of the turn. Of course, on a straight road the distance is the same for different speeds, thus the difference in elapsed time varies inversely to the speed.
  3. The time difference for a small increment in speed is independent of the initial speed. Let v = initial speed, A = max. lat acceleration, theta = turn angle (90deg in your example) The radius for the given speed and lat acceleration is r = v^2 / A. The length of the circ segment L = (pi) (theta / 180) r = (pi) (theta / 180) (v^2) / A The time for the segment t = L / v = (pi) (theta / 180) (v) / A Take the derivative, dt / dv = (pi) (theta / 180) / A For a small change in speed dv, the change in time dt = (pi) (theta / 180) dv / A. Example (Turn 1): theta = 90 deg A = 0.8g = 7.848 m/s^2 dv = 1 mi/h = 0.447 m/s dt = (3.14159) (90 / 180 ) (0.447 m/s) / ( 7.848 m /s^2 ) = 0.0895 s
  4. It happened for me while taking level 3... it had started to rain and I got distracted by that and a passing rider (first mistake) and misjudged the entry speed for a slow corner (second mistake) causing a scary feeling rear slide... which worked out OK and actually looked rather cool on video after. The only things I remember doing are keeping the throttle steady and relaxing my arms.
  5. I heard Will mention to another student last week that the school currently is using GPA's instead of Q2's because Dunlop apparently can't produce and distribute Q2's fast enough... Interesting... Perhaps we'll get some real-world comparisons of the Q2 v. GP-A, e.g. wear rate, qualitative impressions from students, etc.
  6. Dunlop Q2s on the student bikes; Coach bikes, IIRC, race take-offs.
  7. Superbike School student (age: 75) review
  8. This is good advice regarding sighting laps; I would think some homework reviewing track maps, pictures or videos might help too. The track entry and exit is another thing to consider, to anticipate other riders entering and exiting. This is more troublesome at certain tracks where riders enter on higher speed sections.
  9. Is this a pic from your recent track day following CSS L1? For simplicity let's assume the knee and elbow sliders are just hovering above the surface. As a consequence of Newton's Third Law, it is not possible for the rider to exert a net lateral force on the bike as there is no counter force. That is, nothing to press against. The rider's weight (vertical force of gravity, downward) is countered by an equal force of the bike pressing against the rider vertically (upward). There is a net torque which results from the offset of the point of application of the vertical forces.
  10. I agree with the technique of one steering input and then relax through the corner.
  11. If the bike and rider form a rigid body (rider is locked-on the bike) then the center of mass and inertial moment are independent of the attachment point. Now if the rider lays down on the tank instead of sitting upright this will get the rider's mass closer to the bike's center of mass. With the rider locked-on, the net forces on the bike are determined only by the rider's relative position w.r.t. the bike. A lateral displacement of the rider to the inside does have a a slight leaning effect, which is the equivelent of a streering torque of +1..4 Nm. Since most bikes have a small negative steering torque at typical lean angles and path curvatures, an optimal hang-off position will completely balance the steering torque, resulting in neutral steering. IMHO the only use of peg weighting is for pivot steering.
  12. I only use the rear brake at low (parking lot) speeds. I'm still perfecting the basic cornering skills, so rear brake is more a distraction at this point.
  13. ... permits exact application of throttle control rule #1 ... (from memory, don't have my TOTW with me at the moment)
  14. There is not a specific minimum pace required, however it IS a race school. It is a VERY demanding day, with an enormous amount of riding and a focus on racing; for a slow-pace rider Level 4 might be a better choice. Technically, Levels 1-3 are not an absolute requirement, but they are very strongly recommended. If you had not taken at LEAST Level 1 and 2 you would be spending most of your time trying to catch up on that material and would not get the most from your time at CodeRace. The answer about pace is a bit vague - the pace varies from year to year, depending on who comes, and the school does not have a specific pace or laptime requirement. Mostly it will depend on your comfort level. My personal opinion is that if you are intimidated riding in the slow group at a local trackday, Level 4 would be a much better choice than CodeRace. But, if you are very comfortable riding trackdays, and you are contemplating doing some club racing, it's perfect and a great intro to racing - WAAAAYYYYY better than taking the local club race intro school - you get to practice starts, try different lines, get experience with the flags, learn about passing, etc. Make sure you SIGN UP REALLY EARLY, CodeRace fills up fast. Hotfoot, Thank you for the advice. Recently did my first track day in Keigwin's B- group. I didn't feel intimidated, was definitely in the slower half of that group, though not the slowest. Based on that experience the race school is likely premature. This season I plan a few level 4 days plus more practice in B- or B. Question - Where to find info on passing. Now that I'm not the slowest I need to learn to pass instead of slowing down. Regards, Matt
  15. If you're signed-in to your google account, you may block sites from search results (e.g. answers.yahoo.com) Add blocked sites in "Search Settings"
  • Create New...