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 To accelerate or remain constant, that is the question
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rayg50
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Posted - 06/20/2011 :  10:11 PM
quote:
Originally posted by Mikeydude

In this situation:

Are we calling accelerating = increasing speed?

Or are we calling calling accelerating = lightly rolling on the throttle to maintain speed?

I shouldn't jump in here but I will because words are getting in the way of understanding. They are being played with so much in this thread that it IMO it has become more confusing than it needs to be. So I will give you my interpretation.

Accelerating = going faster (increasing speed as you point out).
Maintaining speed = neither going faster nor going slower.

Separate from that is what we do to accomplish them. What you do is different if you are in a car or plane or motorcycle or sailboat. Since we are talking motorcycles the throttle comes up as the weapon of choice but only as the tool, and it is not the only tool. If I were on a straight road with a 45 degree downward slope and I wanted to maintain speed I suspect I would not be rolling on the throttle.

However, on a curve that was not downhill, whether I wanted to maintain speed or increase speed I would need to roll on the throttle to wind up with that feeling that the "Bike felt great and I felt more in control" (to stabilize the bike).

My position is that too much of a good thing is bad. Maintaining speed is good increasing speed is bad from the ENTRY to a curve up to the bikes apex. Once past that point everything I have read says you accelerate out of the curve.

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(Deleted or Lost)

Posted - 06/20/2011 :  10:15 PM
quote:
Originally posted by gymnast


Anyone concerned with the subtleties of "upsetting the stability of their bike while in a curve" is likely going far too fast to begin with and needs to do a bit more thinking about the compatibility of their riding habits within the normal parameters of safe and legal operation of their motorcycle. On the other hand it is a good thing to maintain a constant safe speed throughout a curve by the correct use of the throttle (adding, maintaining, or reducing throttle) to maintain an appropriate speed for conditions.

Fair point and worthy of maintaining in mind... however, it's NOT what the topic of the OP was about.

The original question was, is the roadcraft manual strictly correct in it's statements and recommendation to maintain a constant speed in a corner because it provide the maximum stability AND maximum traction. (It's been confirmed that the constant speed constant radius approach provides the most stability - whether it provides the maximum of any other performance aspect of cornering is still in question.)

This advice appears to conflict with the most advocated method for cornering, which recommends using modest acceleration due to it's apparent, actual or perceived benefits.

I don't know what else people think I'm doing here, but what I think I'm doing here is trying to understand both approaches.
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(Deleted or Lost)

Posted - 06/20/2011 :  10:22 PM
quote:
Originally posted by rayg50



Originally posted by Mikeydude

In this situation:

Are we calling accelerating = increasing speed?

Or are we calling calling accelerating = lightly rolling on the throttle to maintain speed?

I shouldn't jump in here but I will because words are getting in the way of understanding. They are being played with so much in this thread that it IMO it has become more confusing than it needs to be. So I will give you my interpretation.

Accelerating = going faster (increasing speed as you point out).
Maintaining speed = neither going faster nor going slower.

Separate from that is what we do to accomplish them. What you do is different if you are in a car or plane or motorcycle or sailboat. Since we are talking motorcycles the throttle comes up as the weapon of choice but only as the tool, and it is not the only tool. If I were on a straight road with a 45 degree downward slope and I wanted to maintain speed I suspect I would not be rolling on the throttle.

However, on a curve that was not downhill, whether I wanted to maintain speed or increase speed I would need to roll on the throttle to wind up with that feeling that the "Bike felt great and I felt more in control" (to stabilize the bike).

My position is that too much of a good thing is bad. Maintaining speed is good increasing speed is bad from the ENTRY to a curve up to the bikes apex. Once past that point everything I have read says you accelerate out of the curve.




Accelerating in the context I've been using and have stated several times is approximately 0.1G.

Keith Code advocates modestly, gradually and continuously rolling on the throttle as soon as practical once the initial steering input has finished - in other words, as soon as you the rider are comfortable. In a short corner, it might make no sense to roll on before the apex... in that case, as far as your concerned, it's not "as soon as practical" after completing the steering input.

And just a reminder, we are talking about an entry which is a neutral balance, constant speed, off the brakes entry.
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rayg50
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Posted - 06/20/2011 :  10:38 PM
quote:
Originally posted by Robsalvv
You're singing to the choir Ray. :-)

I have the definite feeling I am not.

Where my frustration is gathering momentum is that I have never in my life run across a universal solution to anything. There will always be exceptions. Therefore discussions tend to be for the most common occurrence. Public road surfaces have so many exceptions even coming to agreement on the basics may not prove possible

Please re-word 4, 6 & 7 so they work for you. I may just make my point without them and then withdraw from the thread.

I thought I had answered your question about the fixed radius turn but let me reword it. In a curve at the beginning you are headng in one compass direction as you progress along the curve their comes a point where you begin moving in the opposite compass direction that is what I would pick as the apex. A second example would be if you look at the letter "U" the point at which you are no longer heading down but are heading up would be what I would refer to as the apex.

I do sleep well so I am going to bed. I need my beauty sleep.
Cheers Ray

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CaptCrash
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Posted - 06/20/2011 :  10:44 PM
Usually get my butt handed to me in these sorts of conversations...but so be it.

Robsalvv--I understand that you're "looking to understand" but, having spent years around really, really passionate religious folks I'm going to tell you how this looks to an person on the outside looking in.

It appears that you have a very solid and comfortable belief that the RoadCraft approach is the correct one AND (this is where the religion comes in) you're looking for a conversation that ends with: "You're right. RoadCraft is right". Kinda of like when someone comes to the door and says, "You would agree that people want to be happy, yes?" I say yes. They say "We should live closer to God's law, yes?" and then well, heck, you're leaning on the doorpost for several hours agreeing and then saying, "Yes, but..." Until you finally have to say: "Dude. God rocks. You're right. I have to go shampoo the cat or my wife will kill me."

As long as I can remember (1981) whenever I've spoken to anyone about cornering they've given two priceless bits of cornering wisdom:

1. In fast? Out dead. In slow? Out fast. (Racers hold to this).
2. Chop it and drop it (constant or increasing throttle).

They are wonderful, wonderful axioms. It works. The argument that you're having here seems to be, well, ticky-tacky. To me it feels like you're looking for one answer and will carefully poke the bear until you get it.

I would offer you make a statement of belief (tack that manifesto to the church door) and then say: "Prove me wrong." No offense but you don't feel like a seeker you feel like a missionary.

My 2 cents.

***afterthought. Rob, what sort of training in RoadCraft have you received--you mentioned some earlier. Are you an Instructor or simply a practitioner?

Edited by - CaptCrash on 06/20/2011 11:06 PM
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(Deleted or Lost)

Posted - 06/20/2011 :  11:34 PM
quote:
Originally posted by rayg50


I think Robsalvv is having trouble understanding that. The pity is that he raised an interesting point but appears more interested in winning a word game then shedding light.

That's a disrespect that is not warranted mate.

In the past on this forum, I have been chastised for not choosing words and their meanings carefully. I'm not interested in winning a debate, but I will point out inconsistency where I see it.


quote:
Nor should you change your mind. IMO roadcraft is an excellent model to be followed by all riders.
No argument. To my mind, the context of the chapter in question is about grip as it relates control to grip. Rider5 doesn't agree. But as it turns out, following a conversation we've just had, he has given me a context to consider.

The chapter is actually about an overall umbrella called "control" with reference to the bike and rider and the rider's goals being all considered in one... whereas modest acceleration is about maximum machine control.

That's a definitional difference that works for me.


quote:
What is being proposed by RobS IMO is not something many could apply even if the logic were correct, which I do not believe to be the case. It is just not street riding for fun applicable. How many riders do you know that could come close to being able to know how much throttle will produce a .1g acceleration? Of those how many could consistently do it regardless of all the variables that different curves provide? When asked about the 2 riders entering just below the traction roadcraft provided the answer not KC (do not do it).
Ray, your prejudice and bias is showing. Even newb riders grasp the concept of modest acceleration. KC talks about the sensation of acceleration of a 4th gear roll on from 4000 to 6000 RPM (IIRC). The point is, it's very easy to feel no acceleration, negative acceleration or some acceleration. 0.1G doesn't have to be precisely 0.1G. It's just not "hair of fire" amounts of acceleration which appears to be the subtext of some of your posts.

And with particular reference to the bolded part of your quote, if you wish to maintain an honest discourse, I would ask you to be honest in your representation of the "opposing" information. The KC and as it turns out Lee Parks, MSF and most other motorcycle RTO's method of cornering advocates entering a corner at a safe speed and using modest acceleration to provide maximum handling and traction. If it's not something that most riders are capable of, then why is it the most taught technique?

But again, is zero acceleration dangerous? No it's not. Does it provide the maximum machine control. No it doesn't. Is it dangerous not to have maximum machine control, no it's not. Is there plenty of control with zero acceleration? Yes there is.

The effort to paint the most taught cornering technique as dangerous is disingenuous.



quote:
I am only part of this thread because I do not want a rider going off the road because they actually buy into unsafe practices.


Ray, if you are genuine in this belief, then I presume you're about to write to the organisations that teach modest acceleration and warn them of the dangers. ?


Just to put this in context, in a corner that lasts say 4seconds between completed steering and back to vertical - so a typical moderate sweeper - assuming good sight lines, a rider following the most advocated method might exit at 14 - 20km/h faster than they entered - less if they delayed their roll-on. To paint this as dangerous with riders speering off the road is disingenuous.
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(Deleted or Lost)

Posted - 06/20/2011 :  11:54 PM
quote:
Originally posted by rayg50



Originally posted by Robsalvv
You're singing to the choir Ray. :-)

I have the definite feeling I am not.

You want an intellectually honest and frank discussion. You are wishing to set the points of agreement. I'm on the same page.


quote:
Where my frustration is gathering momentum is that I have never in my life run across a universal solution to anything. There will always be exceptions. Therefore discussions tend to be for the most common occurrence. Public road surfaces have so many exceptions even coming to agreement on the basics may not prove possible
The modest acceleration in a corner is a goal if it can be applied to the corner - not always the case. It however, from a dynamics of motorcycling point of view, is universally applicable to all conventional motorcycles - if not, I am in error and will note the exceptions.


quote:
Please re-word 4, 6 & 7 so they work for you. I may just make my point without them and then withdraw from the thread.
As stated, what they contend doesn't hold in the circumstances I mentioned. Make your points with that information in mind.


quote:
I thought I had answered your question about the fixed radius turn but let me reword it. In a curve at the beginning you are headng in one compass direction as you progress along the curve their comes a point where you begin moving in the opposite compass direction that is what I would pick as the apex. A second example would be if you look at the letter "U" the point at which you are no longer heading down but are heading up would be what I would refer to as the apex.
And in a 90 degree turn? Your point defined the Apex as that point which had maximum lean and maximum traction demand. Where is that point in a constant radius constant speed corner? We can choose the midpoint such as the bottom of the U, but that doesn't hold true for the statement you wrote as a point of agreement.

Is such a corner relevant to your subsequent discussion?
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(Deleted or Lost)

Posted - 06/21/2011 :  12:04 AM
quote:
Originally posted by CaptCrash



1. In fast? Out dead. In slow? Out fast. (Racers hold to this).
2. Chop it and drop it (constant or increasing throttle).



I'd say racers hold to, "In as fast as practical. Out faster."

So CaptCrash, you'd agree that "in slow, out fast" is an often quoted credo in cornering. Is it purely for speed or because it imparts other benefits? AFAIK, it's what's most often taught.

This is what tripped up my eye about the roadcraft manual, as it definitely doesn't advocate that - infact advises against it... but I now have a working understanding of why roadcraft advises what it does. It's NOT focussed purely on the bike.
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rayg50
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Posted - 06/21/2011 :  6:14 AM
quote:
To paint this as dangerous with riders speering off the road is disingenuous.

Here is my difficulty. You argue for greater stability. I quite possibly misinterpret this as an attempt at greater control. IMO if the bike is under control (stabil) to begin with, there is no benefit other than bragging rights to having it "more" under control (stabil). I have seen no argument that says more control is needed than what maintaining speed provides. That leaves me wondering where the benefit lies in modestly increasing speed other than getting through the turn faster. That is the light I am waiting for you to shed. I cannot contest or agree with what has not been presented. If I am applying sufficient force to keep something from dropping from my hand applying more force is not needed unless there is something I am not considering. Give me that thing that I am not considering.

I presented what I thought to be a valid downside to which I expected something more palpable in response than to not do it. We are in agreement. The rider should not enter at the limit of traction but that still does not counter the argument. Give me an opposite position, if you are not in agreement, that I can consider. I believe I have done so for you. If I have missed it please restate it.

Let us see if we can agree on the following. I will keep it short.

As you enter a curve and proceed through it the demand on traction increases at some point in the curve the demand on traction begins to decrease.

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James R. Davis
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Posted - 06/21/2011 :  7:13 AM Follow poster on Twitter  Join poster on Facebook as Friend  
quote:
As you enter a curve and proceed through it the demand on traction increases at some point in the curve the demand on traction begins to decrease.

Rayg50,

For some reason you have the word 'apex' in mind but have confused it with 'midpoint'.

In a constant radius curve ridden at constant speed, there is no 'high point' (apex). In an outside-inside-outside run around a corner (90-degree turn), it is often said that the 'apex' is the closest point when on the inside part of that turn, but that is a misuse of the word.

In any event, traction remains constant throughout a constant radius curve ridden at constant speed.
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CaptCrash
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Posted - 06/21/2011 :  8:06 AM
quote:
Originally posted by Robsalvv


I'd say racers hold to, "In as fast as practical. Out faster."

So CaptCrash, you'd agree that "in slow, out fast" is an often quoted credo in cornering. Is it purely for speed or because it imparts other benefits? AFAIK, it's what's most often taught.




I'd say Racers hold to: "I want go as fast as possible through a turn. I don't care if the bike squirms and argues and screams and operates at the edge of the traction envelope." Their goal is simple, raw speed. For Racers speed is goal. Crashing at high speed is not the goal and Racers are willingly sacrifice safety and increase risk for speed. Risk goes up, times go down.

Excuse the philosophy talk but speed does have a function of diminishing returns. It stabilizes--try a corner way too slow, say a 35mph advisory turn at 10mph, the try it at 35mph with a constant or slightly increasing throttle.

I also would offer this: The US safety model is build upon the idea of "Managing Risk", the idea that riding is a risky business, you can get hurt and that risk is minimized but never removed (In all honesty you should know that I have been trained by the MSF in the RSS and by Idaho STAR in the BRT and EC and am currently and Idaho STAR instructor). Adherents to The RoadCraft system seem to say that absolute safety is attainable.

I believe that basic difference in world view is important to remember because a system that promises something has to be able to deliver it. The RoadCraft system may be trying to enthusiastically conserve traction and field of vision/sightlines in the interest of absolute safety--I believe earlier you made a commentvabout RoadCraft and not entering a corner faster than you can get safely stopped in your own lane. (I'm too lazy to hunt it up--but I believe that was the spirit of the idea).

The IDEA of what you want a rider to do in the corner matters vastly. Racers want SPEED and FAST TIMES. Comparing Code and racing lines to MSF or RoadCraft and SAFE or managed risk riding probably isn't fair.

What's your goal in worrying so about these cornering techniques? Are you looking to go faster? Manage and lower your risk? Or achieve absolute safety?

Edited by - CaptCrash on 06/21/2011 8:18 AM
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rayg50
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Posted - 06/21/2011 :  11:43 AM
quote:
Originally posted by James R. Davis
In any event, traction remains constant throughout a constant radius curve ridden at constant speed.

The constant radius curve ridden at constant speed IMO has no place in this discussion since the opposing viewpoint is for modest ACCELERATION. It does not exist in this scenario since the proposal is NOT for constant speed. Make sense?

quote:
you have the word 'apex' in mind but have confused it with 'midpoint'

LOL. The exact opposite is the case I have NO WORD in mind and I am hoping that everyone else will release the word that they hold so dear. If you love it let it go. Let us consider what happens and not what we call it.

What I have in mind is the point in a curve where the demand on traction ceases to increase and begins to decrease. If we really need a word for it I choose AMME. Let us all now use AMME to refer to that point. I imagined it so I get to name it.

I wish to separate what happens as we approach AMME from what happens after we have passed AMME.

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James R. Davis
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Posted - 06/21/2011 :  12:28 PM Follow poster on Twitter  Join poster on Facebook as Friend  
Ray,

Calm down.

In a constant radius turn there is no point at which traction ceases to increase and then begins to decrease.

Traction remains constant on a level roadway regardless of speed. (Except as a result of lift reducing your weight.)

Centrifugal force increases throughout that curve if you accelerate throughout (no matter how slight or aggressively).

Traction reserve, on the other hand, decreases from the moment you enter that turn until you exit it as long as you are accelerating.

There ain't no AMME in that curve, Ray.
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rayg50
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Posted - 06/21/2011 :  5:09 PM
quote:
Originally posted by James R. Davis

Ray,

Calm down.

I am calm (mumble I as I foam at the mouth), LOL. I am actually getting a kick out of this now.
quote:

Traction reserve, on the other hand, decreases from the moment you enter that turn until you exit it as long as you are accelerating.

We are simplifying which is good. So this is the extreme example where traction reserve decrease occurs throughout the curve (as long as you are accelerating).

Mr. Davis, Robsalvv, a couple of quick questions.

Are there any curves where acceleration does not cause traction reserve to decrease?

Does a decrease in traction reserve equate to an increase in traction demand?
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Razzoo
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Posted - 06/21/2011 :  5:28 PM
I think I will take a swipe at an almost dead Equus ferus caballus

Accelerating throughout a curve does not make sense to me.
Slow in (but using slight throttle just maintain speed and keep the chain taunt), then past apex gently accelerate until you are vertical works well for me. Using this technique, the bike seems to stay "planted" throughout the curve. however I have no computer or physics model that proves this is the optimial way to negotiate a curve.

Where could a newbie go wrong using this technique?
They could not understand the term "gently accelerate"
They could not understand apex (or AMME - whatever you want to call it)
They could not understand "slow in" (and so they are at the limit to begin with)



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rayg50
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Posted - 06/21/2011 :  8:43 PM
I've decided to just do what I have done in the past which is to state my point of view and ask that it be torn apart. Those who have followed my posts should recognize that it is not out of character.

The following refers to the vast majority of curves I ride. Your mileage may vary.

1- Acceleration causes weight to shift from the front tire to the rear tire.
2- If you add weight to the rear tire it gains traction.
3- If you shift weight from the front tire it has less traction.
4- As you accelerate in a curve you increase the traction demand.
5- The more you accelerate the more the traction demand

Here are the sticking points where I seek some lighting (you can throw a couple of lights on the previous points also). They seem self evident to me so let me know where I err on any of my points.

6- As you move into the curve the traction demand increases. The sharper the curve the greater the traction demand. So if a gradual curve becomes a sharper curve the traction demand increases accordingly.

7- The combination of sharper curve and increased speed causes the traction demand to increase as you go further in (increased speed alone will increase traction demand as you progress).

AMME has left the building so no points to be made there.

8- A bike has length it is not a single point.
9- The front tire experiences the increased traction demand before the rear tire (in a curve).

So my question / point for clarification is

If the front tire experiences the increased traction demand first why would you employ a method that shifts traction from it? Phrased differently, why would a balanced weight / traction be less desirable?





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rayg50
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Posted - 06/21/2011 :  10:55 PM
quote:
Originally posted by Robsalvv
That's a disrespect that is not warranted mate.


I reread all the posts and you are correct the disrespect was not warranted.

My mind was on your point(s) for acceleration in a curve. If it has acceleration then, in my mind, it ceases to be one that has constant speed and therefore a constant radius constant speed curve was not pertinent to "my" thread nor could it be. Given that the posts preceding my numbered post featured constant radius constant speed your caveat was understandable. I took it to be what it was not.

My comment was not warranted and for that I apologize.

Cheers Ray
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(Deleted or Lost)

Posted - 06/22/2011 :  2:04 AM
quote:
Originally posted by rayg50

To paint this as dangerous with riders speering off the road is disingenuous.

Here is my difficulty. You argue for greater stability.
It's been put to me that to argue that modest acceleration maximises stability is definitionally wrong and I have accepted that. RTO's however argue that modest acceleration increases "stability" (probably not in the definitional sense of the word though), traction and bike control. James states it "maximises handling stability". Riders routinely state it "feels" better. Clearly it improves some performance aspect of the cornering process.


quote:
I quite possibly misinterpret this as an attempt at greater control. IMO if the bike is under control (stabil) to begin with, there is no benefit other than bragging rights to having it "more" under control (stabil).
Many people use the word stability to explain "sure footedness" or some similar ill defined feeling. So I'm not going to buy into the argument any further given that you are now using the term incorrectly. Your continual attempt to link the technique with a poor attitude i.e., "bragging rights" is specious.


quote:
I have seen no argument that says more control is needed than what maintaining speed provides. That leaves me wondering where the benefit lies in modestly increasing speed other than getting through the turn faster
"Needed" is the key word. Is it needed? Maybe not. However I did reference at least four of James's tips that point out the technique and in some argue the benefit of shifting weight rearward. In general, there's greater traction at the rear and a more compliant suspension at the front which allows the bike to more readily track over the bumps and lumps. Is there a need to obtain these benefits? Not really. Would having greater handling, control and suspension compliance be advantageous? More than likely.


quote:
I presented what I thought to be a valid downside to which I expected something more palpable in response than to not do it. We are in agreement. The rider should not enter at the limit of traction but that still does not counter the argument. Give me an opposite position, if you are not in agreement, that I can consider. I believe I have done so for you. If I have missed it please restate it.
The point you are making is made from a flawed position or understanding. The technique relies on a safe entry speed and it relies on the rider seeing that they can and have the option to roll-on modestly. It's not a "must do". It's not a "riding by numbers" approach. Using an argument about riders entering a corner at some ridiculous speed as the straw man to undermines the technique is flawed - like all riding, the technique requires some judgement. Even a constant speed approach requires judgement - at the very least the same judgement to choose a safe entry speed.


quote:
As you enter a curve and proceed through it the demand on traction increases at some point in the curve the demand on traction begins to decrease.
Now this is interesting. This assumes that you are taking a changing radius line such as "In wide, out tight". I agree the traction demand changes and will be at a maximum at the highest lean angle, which you previously described as occurring at the apex. {Just as an aside, the "in wide late tip-in" approach has the highest lean angle well before the Apex - but if I read between your words, your style of cornering appears to have the Apex as the point of highest lean. I'll accept that this is the kind of cornering line you wish to discuss.}

What is interesting about that then is since you have stated your preference is for maintaining a constant speed in the pre Apex phase and accelerating in the exit phase... this means that you MUST BE rolling on throttle throughout the pre Apex phase! This MUST BE true or else as traction demand increased with tightening radius and increasing lean angle, you'd be slowing down due to increasing cornering loads. Since you aren't slowing down pre Apex you MUST be rolling on throttle

It appears that the key difference then, between your preferred constant speed approach and the KC / Lee Parks modest acceleration approach, is the amount of roll on in the pre-Apex phase.

How very interesting.



quote:
Originally posted by rayg50

I've decided to just do what I have done in the past which is to state my point of view and ask that it be torn apart. Those who have followed my posts should recognize that it is not out of character.

The following refers to the vast majority of curves I ride. Your mileage may vary.

1- Acceleration causes weight to shift from the front tire to the rear tire.
2- If you add weight to the rear tire it gains traction.
3- If you shift weight from the front tire it has less traction.
4- As you accelerate in a curve you increase the traction demand.
5- The more you accelerate the more the traction demand

Here are the sticking points where I seek some lighting (you can throw a couple of lights on the previous points also). They seem self evident to me so let me know where I err on any of my points.

6- As you move into the curve the traction demand increases. The sharper the curve the greater the traction demand. So if a gradual curve becomes a sharper curve the traction demand increases accordingly.

7- The combination of sharper curve and increased speed causes the traction demand to increase as you go further in (increased speed alone will increase traction demand as you progress).

AMME has left the building so no points to be made there.

8- A bike has length it is not a single point.
9- The front tire experiences the increased traction demand before the rear tire (in a curve).

So my question / point for clarification is

If the front tire experiences the increased traction demand first why would you employ a method that shifts traction from it? Phrased differently, why would a balanced weight / traction be less desirable?


Point 3 - generally agree. The question of what is the new reduced amount of traction is a good one because in a banked curve the available traction increases and yes, because you're in a curve more traction is also being consumed. I've been on countless rides employing the modest acceleration technique and have never demanded more traction from the front than has been available. I've even used the technique on flat unbanked corners - even though modest acceleration reduces the available traction of the front wheel - however the rear does the bulk of the work in a corner doesn't it?

Point 9 is I think incorrect. Tip 66 would disagree with you.

One of the main arguments FOR modest acceleration is about a less loaded front means more compliant suspension. However what if there's a patch of water? Which cornering scenario is more likely to lead to a front end wash out? The modest acceleration or the constant speed? That's actually a very good question and I believe it's actually a fairly multi layered complex one. Either scenario is better than chopping the throttle and transferring a whole lot of weight forward. But which one has the higher probability of not washing out? My guestimate is that the modest roll on scenario edges out the constant speed scenario - but probably not by much. Even so, if there's an advantage in it, wouldn't you want that up your sleeve?



Edited by - Robsalvv on 06/22/2011 2:57 AM
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(Deleted or Lost)

Posted - 06/22/2011 :  2:47 AM
quote:
Originally posted by CaptCrash


Originally posted by Robsalvv


I'd say racers hold to, "In as fast as practical. Out faster."

So CaptCrash, you'd agree that "in slow, out fast" is an often quoted credo in cornering. Is it purely for speed or because it imparts other benefits? AFAIK, it's what's most often taught.



I'd say Racers hold to: "I want go as fast as possible through a turn. I don't care if the bike squirms and argues and screams and operates at the edge of the traction envelope." Their goal is simple, raw speed. For Racers speed is goal.
So "in slow, out fast" isn't exactly the racers creed as you stated earlier. I think it's a performance cornering creed.


quote:
Excuse the philosophy talk but speed does have a function of diminishing returns. It stabilizes--try a corner way too slow, say a 35mph advisory turn at 10mph, the try it at 35mph with a constant or slightly increasing throttle.

I also would offer this: The US safety model is build upon the idea of "Managing Risk", the idea that riding is a risky business, you can get hurt and that risk is minimized but never removed (In all honesty you should know that I have been trained by the MSF in the RSS and by Idaho STAR in the BRT and EC and am currently and Idaho STAR instructor). Adherents to The RoadCraft system seem to say that absolute safety is attainable.
The roadcraft system is extremely robust. It assumes very little about the road you're traveling on and assumes even less about the road beyond the point which you can see. The IPSGA approach requires ongoing scanning, hazard prioritising and planning using information you garner from what you see and deduce from what you see. It's a system that bring the rider into the present moment at all times. As a result, it is highly defensive and about as safe as one can be on two wheels on the public road.


quote:
I believe that basic difference in world view is important to remember because a system that promises something has to be able to deliver it. The RoadCraft system may be trying to enthusiastically conserve traction and field of vision/sightlines in the interest of absolute safety--I believe earlier you made a commentv about RoadCraft and not entering a corner faster than you can get safely stopped in your own lane. (I'm too lazy to hunt it up--but I believe that was the spirit of the idea).
Yes that is exactly what roadcraft specifies.


quote:
The IDEA of what you want a rider to do in the corner matters vastly. Racers want SPEED and FAST TIMES. Comparing Code and racing lines to MSF or RoadCraft and SAFE or managed risk riding probably isn't fair.
True. I did mistake roadcraft making a statement about maximum machine control. It is not. KC/Lee Parks are however making such a statement.


quote:
What's your goal in worrying so about these cornering techniques? Are you looking to go faster? Manage and lower your risk? Or achieve absolute safety?
I was trying to resolve how two different systems could both say that they provided maximum machine control. They don't. Roadcraft provides maximum control in a holistic sense. The KC approach gives maximum machine control quite specifically. I hope that clarifies things.




quote:
Originally posted by Razzoo

I think I will take a swipe at an almost dead Equus ferus caballus

Accelerating throughout a curve does not make sense to me.
Slow in (but using slight throttle just maintain speed and keep the chain taunt), then past apex gently accelerate until you are vertical works well for me. Using this technique, the bike seems to stay "planted" throughout the curve. however I have no computer or physics model that proves this is the optimial way to negotiate a curve.
No argument from me. I never said a constant speed approach wasn't a 'planted' way through a corner. But if you're taking an in wide/out tight approach however, you MUST be rolling on throttle to maintain speed pre apex. Modest acceleration then is a slightly more aggressive roll on. There's not a huge difference in the approaches is there!


quote:
Where could a newbie go wrong using this technique?
They could not understand the term "gently accelerate"
They could not understand apex (or AMME - whatever you want to call it)
They could not understand "slow in" (and so they are at the limit to begin with)
Ok, I will grant a noob might possibly have these misunderstandings... I suspect however that a genuine noob is near soiling themselves at any speed that gives them a sensation of speed, especially as they approach a corner. Most noobs fear lean angle so they are likely to self limit their speed by default. I mentor noobs regularly. I'm often reminded at how they naturally use very modest and conservative approach speeds since I'm often dawdling through corners (or so it feels to me).

I'll argue one point however, every riding noob has a concept of acceleration. They feel it when they take off from the lights or accelerate down an entry ramp on to a freeway. In my experience asking them to accelerate gently is not a big ask. It's not a race, there's no prize for being first, they are afterall exploring what just enough acceleration in a corner feels like, starting from the position of there being no acceleration, i.e., enough cracked on throttle to maintain a constant speed.
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(Deleted or Lost)

Posted - 06/22/2011 :  2:50 AM
quote:
Originally posted by rayg50

I reread all the posts and you are correct the disrespect was not warranted.
No problems mate. Thank you. Let's get back to talking motorbikes :)


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