Lnewqban
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Posts posted by Lnewqban
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Seriously, thanks again - I now have *more* than enough to work on next track day. Unfortunately that looks to be a month off...but it will be at my regular track, so I can gauge my improvement from the lap times.
Just focus on the important:
http://forums.superb...p?showtopic=579
"If you think what I am saying is: you have to push through the fear barriers to get to clean riding, you are right; but the push comes after the understanding of where your attention should or should not be focused.
.........There are basic principals to riding. What you ride doesn't change them. Where you ride doesn't change them. How fast you ride doesn't change them. They are what they are: they are not based on my opinions about them, they are based on well defined and easily understood basic principals you will understand.
.........It has taken 30 years of devoted time and attention to separate the important from the unimportant and to figure out ways we can trick ourselves into giving up the resist-error-resist-terror way of doing things in favor of the focus-flow-focus-go mode............."
Keith Code
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Yes, I think there is a bit of a logical flaw, in the assumption that "maximum lean" means the tires are at the limit of traction. That may or may not be true on a given bike with a given set of tires on a given track, but most often it won't be. Lean angle is usually ground clearance limited, yes? So, in most cases at maximum lean there is still *some* tire traction available for acceleration, right?
This is just a logical argument on my part because I have never experienced maximum lean on any motorcycle that wasn't severely ground clearance limited (low pegs, etc)...but I think it makes sense.
There is the lean angle of the bike and there is the lean angle of the bike-rider system.
The hang-off technique allows the latter to be higher than the former.
Check this old post and schematic:
http://forums.superb...indpost&p=26467
As you can see, the limit of traction (360 degrees around the contact patch) is reached only when the resultant lateral force on the patch grows up to the magnitude of the maximum static friction (force normal to the patch times the static friction coefficient).
The lean angle of the system (bike-rider) is a visible gauge of the rate of those two forces: 26 degrees mean that the friction force is half of the normal force.
The recommended 0.1G acceleration during a turn that Code recommends does subtract just a little of the maximum lateral allowable friction; however, it introduces a bigger benefit: to allocate a distribution of weight (40 front / 60 rear) that works in harmony with the design of the front and rear tire-suspension systems.
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..............One that I only recently understood was that tyres actually have more rubber on the ground, and more traction when on the side of the tyre than when on the centre!.................
I really love your posts Mugget, but I would like you extending your explanation of the quoted statement.
Here is a good article for the OP to read:
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Are you serious? What ###### advice!
I am serious, indeed!
My point is that, if done by the book, you will not be able to fall even if you push it beyond your current mental limit.
In order to lean more and stay rubber-down you need to understand and conquer your fear.
Riding that turn free of that fear, you will lean more, down to the physical limit, without experiencing the outcome that you fear now.
Easier said than done, I know.
This is not about motorcycling, this is about an irrational fear that bothers you and limits the performance of your bike.
It is irrational because others passing you show you that the bikes can physically do it.
The difference is that those riders do not interfere with the physics behind the process of taking a curve.
They don't interfere because they have learned, in a classroom or by falling, that any fear they feel will create problems for the bike.
Chapter 7 of A Twist of the Wrist II explains the whole thing very well.
I have fallen due to the front, the rear and both tires and is not as bad as your mind makes you believe it is.
Your survival reaction is nothing more than an exaggerated fear to an event that is perfectly survivable.
Relax, my fiend, and just enjoy riding..........and even falling eventually.
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Thank you all much; I am really learning from your interesting posts.
Do you carry a safety factor into the curve, regarding entry speed?
Like a special technique that you reserve for the case of an error for excess, traffic situations, etc.?
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...... How do I stop the alarm bells from going off when I reach that higher lean angle? How do I convince myself that I can carry 45 degrees of lean or more around a slow corner and not lowside? What is a good method to build up my confidence?
Just find the lean angle at which the bike will low-side.
If you use the 40/60 rule for weight distribution and leave the steering bar alone, you may not be able to induce a low-side before the metal parts start scrapping the pavement.
Have you fallen on a track before?
Is really that terrible?
This is like dancing, you have to flow, feel and enjoy.
I can't see any joy in the face expression of those pictures.
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Thanks, guys.
Re-reading my previous question it sounds silly somehow.
I believe that the reason of my question comes from my observations of that 180 degree turn in our local track, where I see riders (races and track days) not doing the visual technique (at least not in an obvious manner) and not following the line corresponding to a double apex turn.
At least to my ignorant eyes, it seems that they run the interior of the turn and are stuck on the gas, except during the last 20 or 30 degrees of the turn.
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2-step is a vision technique. If you can't see, you can't really use it, can you?
If you can't see the shape of the turn, you can't really choose an apex or turn point, you simply have to wait until you are far enough into the turn to see how it's shaped, and THEN you can choose your points and apply the 2-step. A new rider, unfamiliar with the 2-step, might find their eyes drawn to the inside of the corner, and unintentionally steer the bike there, and end up riding around the inside edge of the corner - not ideal, since it tightens the curve AND makes the visibility even worse. 2-step helps with this as well.
Is this 2-step visual technique used in actual racing or track days?
I ask because, in Florida track days, I have seen a lot of "riding around the inside edge of the corner", especially in turns close to 180 degrees.
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As the discussion has evolved from selection of entry speeds to quick flick and turning points, how are those related to the Code's statement about the flick rate determining the entry speed?
"Your quick turn abilities determine your corner entry speed. Period."
For me it reads like this:
You can turn the bike X degrees by either following a long radius turn or one or several very short radius turns.
By quick flicking the bike, you can achieve a great amount of degrees of turn without going to extreme sustained lean angles.
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I develop this SOP hoping there is a more optimized solution for public roads... anyone has an even better plan??
Study the road via Google Earth before leaving
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..........Back to the OP: 1. I am still struggling with getting my speed perception right in track so still enter bends too slow. You do get the ride each bend many times though so you can finely tune your speed.
2. Road riding and unfamiliar bends: unless you like hospital food then really you have to sit in the fact that you're not going to be riding at 100%. Equally you can't necessarily apply the 2-step because you need at least one RP, and unless it's a familiar road you'll have none at all. No RPs means we have to take a different approach hence the wider entry for better visibility, and using the vanishing point (in slow out fast, for this reason). You don't need these on a track because you know (learn) where then bend goes and you don't need to see round it, there aren't any cowpats, cars etc. around it.
In Level 1, as far as I can remember, RPs are looked at and you experiment by moving your RP deeper into the turn as you increase the turn-in rate once you've got quick turns. In Level 2 this is followed up (RPs) but really we all ride different lines so you haveto choose your own RPs, and also move them as your pace changes or you find better lines. They're an itertive thign though so RPs on an unfamiliar road will be near-impossible on the first ride through.
Thanks Johnny, very good response!
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The point here is that while you can't change the road, you may be able to change other things in your riding that could improve your confidence in entering those blind turns, giving you more certainty in choosing your turn point, how and where to steer the bike, and choosing a workable entry speed.
Some crash statistics from A Twist of the Wrist II:
"Factually, it's uncommon to go into a turn too fast! Watch racing for 20 or 30 years and tell me what you observe. My eyes tell me going in too fast is low on the scale of crash causes. It is rare. Going in with the brakes on too hard and crashing is another thing; that causes crashes fairly often and is an obvious rider error. That most riders misjudge their turn-entry speed, usually on the slow side, is a major stumbling block to clean and quick turn execution."
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Thank you very much, Hotfoot; my misconception is perfectly clear now.
Sorry, it is hard for me to explain things in clear manner in English.
I believe that your #5 question is the one.
I only had one track day in the Novice group in Florida (not CSS); therefore, I am very ignorant about how picking an efficient entering speed is done for racing and more advanced track day's groups.
The control riders made that selection for our group, and I felt comfortable and SR's free during the day.
One thing did bother me at the end of that day: without the control riders, I would have been completely lost about how fast should I be rolling just before releasing the brake and flicking the bike.
That was the main reason of my first post: I didn't know what was the proper technique to judge and reach an efficient and consistent speed for a particular turn under track conditions.
Normally I don't make mistakes that trigger any SR while riding on the street, mainly because I have many years of experience judging street entering speeds and because the bike is moving far from its physic limits there.
However, on a track, I will sure go in either too slow or too fast.
Reading braking techniques in Code's book, I learned that initial hard braking allows the rider to fine adjust the entering speed.
This speed is something precise and critical, I thought: a little low or a little high must be bad for the optimum track turn over a selected line.
That is what made me wrongly assume that the rider would rely on some speed indicator for that level of precision.
Thanks to everyone's responses, now I understand that the principle is the same than for street riding: practice, practice and more practice.
Quoting Hotfoot: "Judging entry speed is an art....... it is something you need to be able to choose for yourself, on every turn you ride."
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Thanks, Hotfoot.
Let me ask you some questions, to help you sort through this:1) Is there one ideal entry speed for each turn, that will work for every rider, on any type of bike? Or is entry speed an individual thing, dependent on your bike, setup, skill level, the day's conditions, etc.?
No, each case is different, unless all conditions are very similar, like in a high performance race. However, I believe that there is a physical limit that can be seen those racers hit.
2) Have you ever entered a turn at a speed that triggered one or more of the survival reactions listed on page 3 of A Twist of the Wrist II?Certainly.
3) If you wanted to enter a turn faster (at the track, where you get to ride that turn repeatedly), would you want to make BIG increases on each lap or small, incremental ones, as you experiment with it?Small, incremental ones. However, without looking to the speedometer, I believe that I wouldn't be able to do it in a stable increment, since small increments would be hard to feel.
4) Could looking down at the speedometer when entering a turn interrupt your visual flow? How would that affect your sense of speed, and your comfort level entering the turn? Have you ever been looking down at the dash of your car (or at your phone!) and then looked up to see a car stopped in front of you? Did that momentarily mess up your perception of how fast you were approaching that car?Yes to all.
5) if you DID enter a turn slightly (not dramatically) too fast, are there any indicators that could tell you that your entry speed was too high?If subjectively too fast (actually doable but not according to my previous experiences), SR's will be triggered.
If actually too fast and I do commit to the turn using correct techniques, tires will start skidding.
6) Would greater confidence about where the bike is going to go, and in your ability to steer it effectively, help you increase your entry speeds?Yes.
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Thanks to all.
I have been a street rider for long time; hence, I have a better idea for the street.
Just by observing speed limits, the safety margin is huge.
However, for track day (here in Florida), the Novice class was told just to follow the control riders, who were increasing the entering speed for each lap during the day.
I just wondered, what references they followed to select an entering speed for each turn, since that was never explained to us.
Reference points were explained and understood, but I felt completely lost about entering speeds.
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I have finished reading Twist of the Wrist II, hoping to find an answer to this question, but either I missed it or is something obvious.
Please cornering masters and more experienced riders, correct or comment on my two following assumptions:
1) I imagine that for a track, the rider is approaching the limits of traction for each turn, memorizing the maximum entering speed for each turn and observing the speedometer for each entering point.
2) For street riding, each new unfamiliar turn is to be entered at the speed that experience dictates for similar conditions.
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.........
I suppose I'm trying to find the best way to get a heavy bike through esses and to understand what I'm actually doing to bring it about.
Thanks for everybody's comments.
Muppett
No "pushing the bike underneath you" here:
Drill For Learning To Trust The Tires?
in Cornering and Techniques
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Rolling the throttle off doesn't reduce traction of the front tire, but increases the load on it.
Exactly the opposite occurs with the rear tire during roll-off.
The only way to reduce traction is by reducing the force that is perpendicular to the road (normal force).
The transfer of weight onto the front tire increases that normal force, but also the lateral force.
The ratio of increment of the lateral respect to the normal force is higher for bigger angles of lean.
Skid will happen only when the magnitude of that lateral force exceeds the maximum allowable value (red circle in previous schematic).
"Once the throttle is cracked on, it is rolled on evenly, smoothly, and constantly throughout the remainder of the turn." K. Code
Regarding the effect of the roll-on:
According to the book, the proper acceleration rate is 0.1 to 0.2 G.
That means that for every second on the turn, the speed of the bike should increase 2.2 to 4.4 mph.
That rule applies independently from the entry speed.
Max lean angle will correspond with max speed; hence, your entry speed should be less to accommodate the gain in speed along the curve.
The fastest you go, the quicker you will be done with the curve, and the difference between entry and final speed will be less.
The opposite applies for slower trajectories.