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Constant Arc Turn Versus Parabolic Arc


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To everyone at CSS-


Thanks a million for getting my riding to the level it is today. It would have been virtually impossible for me to acquire these cornering skills in any other safe and sane manner...


After digesting everything following the latest two-day camp at the Streets, I'm chewing on this thought. I believe my entry routine has been highly influenced by my bicycles and my Aprilia RS50/75. Since these things have little or no horsepower to speak of, I think I'm programmed to flick the bike into a corner at the lean angle and speed that will carry me though to the apex and out the exit at the same speed as I had at turn entry. I'll call this my constant-arc habit. Apparently this habit kills my exit speed when I ride a bike that DOES have a throttle connected to many more horses than my little scooter. I am under the assumption that to progressively apply throttle through the exit I would experience an increase in my turning radius, i.e. the arc would grow and follow a more parabolic trajectory. Under my constant-arc entry habit, changing the arc to follow a parabolic, drive-tolerant arc would require tightening the arc a bit near the apex... a tighter arc requiring less speed... less speed at the apex requiring a change in entry set-up.


Am I thinking correctly. or are there other factors missing from my reasoning?

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To elaborate, let's call this my constant-arc turn. Sight the little yellow "X" the School staff stuck to the track and continue looking for the apex. Reach the turn-in and flick really hard. Once the lean has been established, I crack the throttle to settle things and continue to the apex, then wait to roll-on until I can do so and still maintain my exit line. It's that WAIT that I'm trying to avoid. Plus, I find myself still cranked over with as much lean towards the end of a turn as I had when I passed by the corner apex. By the way, my latest school drills were based around the pick-up drill and hook-turn drill, each with the goal to try to improve my turn exit speed. These drills were combined with varying my line at entry a bit, and so I'm now sitting here wondering if my entry habits were stalling my progress in exit speeds. If so, then I can change my off-track training and visualization to encourage a different approach to my turns. If not, then I'm in need of more help....

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I wish I could be of more help. I could explain how I evolved in applying Mr. Code's techniques, but it may not be right for you and could be dangerous if said unclearly. I hope you have read Twist of the Wrist II and The Soft Science of Motorcycle Racing. Those two books hold the answer to your questions; and they are not the type of books you read once. They are more like reference books, and as you go back and re-read them you discover more and more things that apply to your riding as it evolves. Fortunatly, Mr. Code is very clear in his writing. I go back to them so often that the binding on my copy of The Soft Science has come appart. Read or re-read them both and you will be led to a detailed description in Soft Science that will give you the exact questions you need to be asking yourself, and 'hows'.


A few things I could say from my experience, not knowing your experience, and not able to be as clear and consise as Mr. Code is:


Your vision skills are paramount to you being able overcome fears and to have a better sense of where you are on the track. (Chapters 20, 21,22, and 23 TwistII) I mention this because most people riding on the street use their brakes to stop at a specific point. Is is common then that your eyes are trained to go down to that point when you hit your brakes. I your case it could be the X. Once you see the X you could be looking at it for too long and you have deprivied yourself the knowledge of where the apex trully is and how it is approaching. I did this coming out of a busstop on to a short straight. Another trainer had put the Xs on the track and since I had never trained with him, I was a little suspect and was going faster than others using my own turn in points. I decided to try his X coming uphill out of some kinks. I saw the X focused on it and turned as hard as I thought I should. I hadn't spent more than a cursury look at the apex and I found my self aimed towards the grass and fence. It was too late and I made a slow landscaping towards the corner workers, who weren't paying attentention, stopping 10 feet from them. No one every goes of the course there.


I knew I did something very wrong, and my coach pointed out many things. Then at the end he said to watch this other rider and look at his head movements. Out of that I have a phrase I say in my head when I'm getting tired or having problems, "Eyes Up And Wide."


I know that a simple answer could be proposed, but I think that you would gain more understanding of your experience as a whole if you went through Code's books and found the answers yourself.


Now, if you find things in the book that don't make sense to you, by all means post.


Good Riding

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I'm already re-reading TOTW/TOTW2, and I was spinning around the thought that I might be in a situation where I need to apply the idea of position turning when I encounter my constant-arc mistake. I don't always find myself waiting for the throttle roll-on, especially when in rapid, technical S-sections. It's when I'm running into a corner followed by a straight that I find myself wishing I had scrubbed a bit more speed off at entry to allow an earlier drive at the exit. I can get that drive now by altering my apex point to be really late and deep in the corner, but I end up covering a lot of real estate with my turn arc before I get on the throttle. I'm fairly sure I've got a handle on the theory behind why I'm experiencing the throttle "wait," but I want to bounce these thoughts off y'all before I go off and re-drill myself and visualize something new. Am I going off in the right direction (and not into the grass)? ;-)

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I think what you are experiencing could be related to a few possibilities. I?ll outline a few and maybe something will ring a bell.


Is it possible that you are rolling on a bit too much through the beginning and middle of the corner? If you were to build speed too early in the corner your turning radius would get larger too soon and you would have to wait to start your drive.


Something I?m trying to improve myself is waiting a little longer to start my drive. I run a lot of mid corner speed. I enter pretty fast and start rolling on right away. My problem is I try to start my drive off the corner a little too soon and I can?t drive as hard as I would be able to if I had waited just a little longer. This was pointed out to me when I rode with the head guy (Steve) of our Ozzy school at Phillip Island. When I would follow him around I would suck right up on him in the beginning and mid corner. I would start my drive and be right on him just past the apex, and then he would start his drive. Steve would drive out of the corner so much harder and would put a few bike lengths on me every time. I could usually make this ground back up going into the corners but when we really started to go fast he would put more ground on me coming off the corners then I could make up going back in and mid corner. Anyway, I figured out that I need to wait a little longer to start my drive, get the bike pointed and then really get on the gas hard!


You state


?I crack the throttle to settle things and continue to the apex, then wait to roll-on until I can do so and still maintain my exit line.?


I?m just wondering how you know when to start this roll on, what is telling you that it?s OK to start this roll on? Have you ever just tried rolling on a little harder? Does it cause you to run wide? Does the bike slide? Maybe you have more in reserve then you think?


In Soft Science Keith talks about having a plan for a corner. Maybe you need to think about your total plan and change the focus a little more towards getting a better exit?


Next time you?re at the track try to pay particular attention to one corner that leads onto a strait, preferably a corner that you spend a little time in and not one that is really tight and over quickly. Each time you go through that corner take note of what your doing and see if you can come up with a way to get a better drive off the corner. Try changing you line, try going in a little slower, try not rolling on as hard in the beginning of the corner, try rolling on a little harder coming out. See if you can put some attention on the corner exit and change stuff up and see what works.


I hope this stuff helps. I can say that you ride very well as we have worked together at the track often. I know you have no problem turning the bike quickly and taking a nice deep turn point so it has to be something else. Corner entry and mid corner speed is a good thing and you don?t want to completely sacrifice this stuff to get a good drive. How much you sacrifice depends on how much power the bike your riding has.

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Thanks for the info. I was tracking on the same thoughts that you described, and in the past I have exhibited a tendency to crack the throttle and roll-on too much and too early and carry too much mid-corner speed to allow a good drive out the exit. It's as if I'm using one pre-corner plan for all corners, and now I'm finding I need to develop some new plans for certain situations. I'm currently stuck with the high mid-corner speed plan and need to develop the stop-turn-shoot plan - as well as the other plans in the spectrum between those two!


I chuckle to myself often after a day with CSS because rarely do I ever use full-throttle when riding with y'all. It's amusing when as the day progresses I discover just how much more I can twist that little tube. I don't have the hours experiencing the acceleration that comes as a result of using the throttle to the stops, and only once can I remember the rear tire squirming under acceleration load at a turn exit. I also tend to not use all the track at exit so I agree that I can roll-on much more aggressively and still stay on the track. Also, I believe my focus has been on getting the bike to turn quickly (I think I do) and not on getting the bike to "un-turn" as well (i.e. pick-up and hook-turn drills). That's the next direction for my training...


BTW, I'm attending the three-day suspension seminar... and my boss is paying for it. Imagine that! ;-)

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