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 To accelerate or remain constant, that is the question
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rider5
Male Starting Member
4 Posts


Melbourne
Australia

BMW

R1100GS

Posted - 06/15/2011 :  1:47 AM                       Like
G'day James and fellow riders, its a pleasure to share this forum with you guys. My question concerns a subject within the manual 'Roadcraft' which I think you are familiar with. Roadcraft advocates that the rider aims to achieve a constant speed through a bend by compensating for the slight loss of speed through opening the throttle very slightly. This is something I agree with and believe to be correct.
My good friend RobSalvv beleives that Raodcraft is in error in saying that the constant speed achives the best outcome in terms of stability and that Keith Codes advice which advocates rolling the throttle on right through the curve produces the best outcome in terms of stability.
I have presented the case that KC is describing a technique suited to the track and an increase in lap speed, but Rob feels that the technique is as suitable to the road as it is the track. I recall the following from a previous post:

"As to accelerating while in a curve ... FORGET IT!! All you want to do is MAINTAIN YOUR SPEED in order to stabilize your suspension. All talk or thoughts about accelerating in order to maintain stability is MYTH!!!

Finally, only racers accelerate out of a turn as a normal practice. Are you a racer? Better, by far, is constant speed all the way through a curve - especially since MOST CURVES can be ridden at the speed you enter them. ONLY when an unusually tight turn presents itself should you need to slow down in order to make it. And, if you don't slow down (because you didn't have to), you then don't have to speed up at its end either.

Could you explain the first part for me please so that I can better explain my case as I'm neither an engineer or physicist.

Regards
Rob Smith

dhalen32
Male Moderator
841 Posts
[Mentor]


Omaha, NE
USA

BMW

R1200RT

Posted - 06/15/2011 :  6:20 AM
Rob:
My answer would be a combination of the two points of view you have described. The "roll" step of the slow, look, press and roll process described in MSF courses is intended to stabilize the motorcycle's suspension and maintain ground clearance for cornering; not negotiate the corner faster. While rolling on the throttle implies acceleration, that is not necessarily the case. When a bike leans into a corner it will actually slow down a bit due to increased drag caused by tire slip angle/scrubbing, change in aerodynamic profile of the bike/rider, smaller effective diameter of the tires while leaning, etc. Thus the rolling on of the throttle that we teach is intended to make up for these factors slowing the bike down. The desired effect is to maintain one's speed selected when the corner begins, maintaining ground clearance and stabilizing the suspension.

However, IF one can see all of the way through a corner and assess that available traction is sufficient to do so, I don't see a lot of harm in a moderate increase in speed (acceleration) while cornering.

I agree with your assessment that Roadcraft is a better solution for the street while Keith Code may be the way to go on the track.

Welcome to the forum!
Dave
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James R. Davis
Male Administrator
17282 Posts
[Mentor]


Houston, TX
USA

Honda

GoldWing 1500

Posted - 06/15/2011 :  7:34 AM Follow poster on Twitter  Join poster on Facebook as Friend  
Welcome aboard, Rob!

Since my opinion on the matter was quoted in the first message (increasing speed to maintain stability is a myth), There is little reason for any additional comments from me on the issue.

I would like, however, to correct something that was just said by dhalen32 - who actually knows better, so this is merely a notice that he misspoke.

By accelerating in a curve you do not 'maintain good clearance for cornering'. Increasing your speed increases the lean angle and, thus, decreases ground clearance.

For the newer riders ... it is popularly held that the reason a bike stands taller as it exits a curve is that the rider increases speed. That is entirely incorrect. It 'feels' correct because that is what happens at slow (less than counter-steering) speeds while in a curve, but when you exceed counter-steering speed (about 10 MPH) your bike 'falls up', not 'down' when you brake, and the opposite when you accelerate.

What actually happens is that when you are coming out of a curve your bike stands taller by itself (with or without acceleration) as you change direction of travel and open up the radius of the turn. That is why it is relatively safe to increase speed at the same time.

So, if you want to, you can increase speed as you exit a curve, but only in racing does it makes sense to do so while you are in the curve.
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dhalen32
Male Moderator
841 Posts
[Mentor]


Omaha, NE
USA

BMW

R1200RT

Posted - 06/15/2011 :  8:18 AM
quote:
Originally posted by James R. Davis

Since my opinion on the matter was quoted in the first message (increasing speed to maintain stability is a myth), There is little reason for any additional comments from me on the issue.

I would like, however, to correct something that was just said by dhalen32 - who actually knows better, so this is merely a notice that he misspoke.

By accelerating in a curve you do not 'maintain good clearance for cornering'. Increasing your speed increases the lean angle and, thus, decreases ground clearance.

For the newer riders ... it is popularly held that the reason a bike stands taller as it exits a curve is that the rider increases speed. That is entirely incorrect. It 'feels' correct because that is what happens at slow (less than counter-steering) speeds while in a curve, but when you exceed counter-steering speed (about 10 MPH) your bike 'falls up', not 'down' when you brake, and the opposite when you accelerate.

What actually happens is that when you are coming out of a curve your bike stands taller by itself (with or without acceleration) as you change direction of travel and open up the radius of the turn. That is why it is relatively safe to increase speed at the same time.

So, if you want to, you can increase speed as you exit a curve, but only in racing does it makes sense to do so while you are in the curve.



Jim:
Actually what I said and what I ment was maintain ground clearance. What I probably should have said is the following: Slow to a speed in which you are comfortable to negotiate the entire corner. Do not chop the throttle while leaning in the curve as this reduces your ground clearance at the worst possible time. Roll on enough throttle to stabilize the suspension and maintain your speed throughout the curve. Only when exiting the curve should you begin to acclerate back up to the posted limit of the road.

Does that read better?
Dave
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James R. Davis
Male Administrator
17282 Posts
[Mentor]


Houston, TX
USA

Honda

GoldWing 1500

Posted - 06/15/2011 :  8:22 AM Follow poster on Twitter  Join poster on Facebook as Friend  
This is what I referred to:
quote:
The "roll" step of the slow, look, press and roll process described in MSF courses is intended to stabilize the motorcycle's suspension and maintain ground clearance for cornering


So,
quote:
Do not chop the throttle while leaning in the curve as this reduces your ground clearance at the worst possible time.

is a restatement of what I objected to, but it remains incorrect even as restated.

Reducing speed in a curve stands a bike taller and, thus, increases ground clearance.

If you are too hot in a curve and begin dragging a peg, surely you would not advocate accelerating.

'Chopping' the throttle does, however, destabilize - something to be avoided while traveling in a curve.
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scottrnelson
Advanced Member
6886 Posts
[Mentor]


Pleasanton, CA
USA

KTM

990 Adv, XR650L

Posted - 06/15/2011 :  9:16 AM
I have a slightly different opinion on this subject (that's why I'm here ).

First off, I've never had any ground clearance issues on any of my bikes, and especially not on the two rather tall bikes that I currently own, so that has never been a consideration for me.

When I'm in a long curve where I'll be leaned into the turn for more than five seconds, I agree with what has been said so far about maintaining speed and that's what I do.

However, most of the turns that I take are sharper and I spend less than five seconds actually leaning into them. I do all of my braking before the start of the turn, so as I lean the bike into the turn I'm off of the brakes and I'm already as slow as I'll need to be. The sharpest turning and biggest lean angles occur at the beginning of my turns - delayed apexes and all that. So as I begin to crack the throttle to "maintain speed" I'm already starting to lean less and reduce how sharply I'm turning. At that point I give it a bit more throttle, continue to straighten up the bike, and start accelerating out of the turn. This feels better to me than trying to maintain a constant speed through the whole turn and has worked well for me over many, many thousands of turns.

So the only places where I don't accelerate slightly are on longer turns, decreasing radius turns, or steep downhill turns. For the rest of them I start accelerating once I'm past the "sharpest turning" section of the curve.

That's my opinion and I can't say whether or not it will work for anyone else.

For reference, this image shows my favorite type of turn and the type I'm referring to, although with no straight sections between these particular curves, I won't be accelerating much exiting any of them.
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(Deleted or Lost)

Posted - 06/15/2011 :  11:20 AM
Welcome to the forums Rob :)

Um, well, to be fair, my mate Rob has put his spin on our difference of opinion... Taa mate! So let me rephrase it.

The police rider roadcraft manual says that maximum stability and grip in a corner is achieved by maintaining a constant speed - presumably your entry speed, as it advocates adding some throttle to account for all the losses Dhalen32 so aptly described. The manual clearly states that constant speed is the goal, not an increase in speed.

Keith Code on the other hand advocates the additional gentle/modest rolling-on of throttle in order to provide a small rearward weight bias while in a corner. 0.1G acceleration will do it. It's not a racing technique. He argues that it's perfectly consistent with the design of the motorcycle and loads up the tyres ideally (proportions as based on their contact patch size) which therefore provides the best traction picture while cornering.

KC's rule number one is: "Once the throttle is cracked on, it is rolled on evenly, smoothly and constantly through the remainder of the turn." - this rolling on is done as soon as possible once the steering input is completed.

He goes on to say. "The basic rule of throttle control can almost always be applied, at any speed, because it holds true for 99 percent of all turns and traction conditions." He mentions a few cases where it doesn't apply... but interestingly the example of a bike at 45degrees and pulling 1G lateral acceleration is not one of them.

One of the other advantages of applying this rule is that it actively fights the throttle chopping survival reaction... but that's not the point of our disagreement. Rob's spelled it out the issue, which cornering scenario provides the more stable, higher traction picture: maintaining constant speed or gently accelerating?

For mine, I'm with Keith Code... but I fully appreciate that the constant speed scenario is the more conservative scenario, less likely to consume the available traction. But let's be clear, the KC method is not about tearing through the corner - the difference in final speed between the two scenarios isn't likely to be that great.


..anyway, I'm going to go trawl the articles to see what the distilled wisdom says...


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Bman123
Ex-Member

Posted - 06/15/2011 :  11:35 AM
The information is in "Motorcycle Roadcraft" on page 70, and it does recommend keeping speed constant through a curve.

If one is worried about dragging something, I'd be of the opinion they were riding too fast unless they are on a track or in the parking lot. At too much above the advisory speed it becomes very difficult to stop in your lane while using threshold braking. Too many people worry about how fast it's possible to go through a curve and not about how fast they can go and be able to stop safely.

I would suggest reading the information on "Limit Point" on page 91 and then considering what you will do. It's especially important with truly blind curves and not so important when you can see across the curve.

As I ride pretty close to advisory speeds, I can make most unintentional small mistakes without a problem as long as I remember to counter-steer. I smoothly adjust my throttle to keep the "limit point" frozen. What this means is I slow a little later than others I observe, but don't use the brakes unless I need to due to a misjudgement. And as the curve opens up at the end, I tend to gradually accelerate sooner than others I observe to keep the limit point frozen if it's safe to do so.

In the curve is where the keeping the speed constant theory falls apart slightly. For instance, in a right curve, (Left in Australia) if I move right (left) a bit for an oncoming truck, (Lorrie?) that reduces my visibility and I slow down a bit to freeze the limit point. The same effect can happen due to an overhanging tree or something that reduces my visibility.

I consider learning to use limit point a skill that comes after a person has counter-steering internalized, they can maintain a precise tire track, and they have an excellent scan for critters.
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(Deleted or Lost)

Posted - 06/15/2011 :  12:07 PM
Here are the appropriate tips (as best as I can reckon) with highlights added for emphasis.

They summarise that traction increases when a bike enters a curve and that modest acceleration will increase the traction of the rear tyre due to weight transfer... but this doesn't go on indefinitely as acceleratiion and higher speeds consumes traction. Also heavy acceleration may cause a rear tyre to let go and further speed gaining acceleration when a bike is leaned at 45degrees is likely to lead to a slide as lateral traction exceeds 1.1G ...so on balance, I think that the articles agree with Keith Code. A constant speed in a corner is not the maximum traction picture.

quote:
Tip 179
...The relationship is not quite linear. That is, when you are leaned over in a turn you have INCREASED the weight on your tires meaningfully (about 30%.) So, that adds overall traction which effectively decreases the g's the tires are taking longitudinally...

...Well, you have been told (even by the MSF) to MODESTLY accelerate all the way through a turn in order to 'load your suspension' and minimize weight shifting. Let me translate that for you. Because you know that lean angle is absolutely determined by speed and radius of the turn, this advise could be read as 'constantly increase your lean angle in a turn.' While that makes perfect sense at low lean angles it is CRAZY at large lean angles.

The key word is 'MODESTLY' - and, if you are near peg scraping lean angles, 'modestly' should be interpreted as 'NOT AT ALL!'



quote:
TIP 74

...What you should understand from this is that using acceleration (speed change) to balance tire loads while in a curve is foolish. (In general, however, you will want some (minor!!!) acceleration in a curve as this tends to increase the slip angle of the rear tire which increases traction, and because you want your rear-end suspension modestly loaded to enhance control.)...

...While a modestly increasing speed makes great sense while you are riding through most of a curve, it is understood that some people find great pleasure in rolling-on their throttle as they exit those curves.

Just a little thought, based on all that we have talked about so far, should now convince you that you must be conservative in this practice while you are leaned over hard, and that you need to be BOTH widening the curve and standing the bike taller as you do it...

...The effect of acceleration on the rear tire is quite different, however. You would correctly assume that weight transfer resulting from acceleration would increase traction on the rear tire. It does, during modest acceleration...

...As the rate of acceleration increases it quickly overwhelms the effect of increasing load on the tire (which increases traction) and begins to consume that traction faster than it is being added...

...Traction is directly proportional to the amount of weight carried by a tire - managing weight transfer is managing traction...

...Rolling-OFF your throttle (or braking) if you are 'hot' in a curve is almost certainly more dangerous than simply leaning farther into the curve - because weight transfer will unload the rear-end which reduces rear tire traction....




Thought I'd add something from this tip - since ground clearance and dragging a peg was mentioned in the run of discussion.
quote:
TIP 45

...There are three things that can be done as soon as you hear/feel a peg scrape:

* Increase throttle - (but note that you are already close to sliding and ANY increase in speed can be all she wrote). This is a VERY DANGEROUS solution and it relies on the fact that acceleration raises the middle of the bike while at the same time INCREASES its lean angle. At best, a momentary and trivial net gain in peg height.

...(The use of throttle to increase clearance is a VERY SHORT TERM GAIN and is quickly followed by the dragging part digging harder as the lean angle overwhelms the modest new height clearance.

Use of the throttle makes most sense, of course, at very slow speeds. At higher speeds it is by far the hardest technique to master in reacting to a dragging component and though I indicated it could 'cure' the problem all by itself, it actually REQUIRES that you simultaneously counter-steer a wider path.)


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(Deleted or Lost)

Posted - 06/15/2011 :  12:21 PM
Bman, in Australia we refer to the limit point as the vanishing point. It is indeed one of the most useful visual features of cornering. It doesn't have a lot to do with the traction picture of a motorcycle though.



While I'm in the insomnia mode - I opened up my copy of Total Control by Lee Parks, chapter 9, throttle control, and he argues that positive throttle in a corner puts the suspension "in the sweet" spot and increases chasis stability in comparison to "coasting through" - which I interpret to mean "constant speed". He says that throttle can effect traction, but doesn't categorically make the link between positive throttle in a corner and improved traction - well not in this chapter.

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rider5
Male Starting Member
4 Posts


Melbourne
Australia

BMW

R1100GS

Posted - 06/15/2011 :  10:13 PM
Some interesting stuff and from what I can gather still nothing to say that Roadcraft is wrong or makes statements in error. However, I guess I'm interested in the following part from James "All talk or thoughts about accelerating in order to maintain stability is MYTH!!!"

I'd really like an explanation of why accelerating to maintain stability is myth.
I suppose I kind of get the issue of increasing traction by accelerating gently, which is exactly what Roadcraft recommends in order to maintain speed. Would I be right in thinking that as you tip and lean and therefore lose speed, by opening the throttle you compensate and therefore get a weight transfer?

Also - does the need for opening the throttle diminish as the tyre begins the return to vertical? So if I'm pulling 5000rpm at 40 degreesof lean with a travel speed of 100Kmh, will I need to maintian 5000rpm to maintain the same speed or will speed increase beyond 100Kmh once the bike is vertical?

Lastly if I have increased stability through the rear tyre increasing traction by accelerating gently up to 40 degrees, is there really a need to continue accelerating in order to achieve even more stability, or is what I have plenty and the quivalent to buying a microwave that cooks a roast dinner when all I need is something to heat beans?

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James R. Davis
Male Administrator
17282 Posts
[Mentor]


Houston, TX
USA

Honda

GoldWing 1500

Posted - 06/15/2011 :  10:27 PM Follow poster on Twitter  Join poster on Facebook as Friend  
Stability is not traction.

Stability is the tendency of your motorcycle to maintain both its course of travel and 'attitude' (lean angle, for example). If a motorcycle is not unstable, then it is already stable. What difference does it make if you increase traction in that situation? Stable is stable.

On the other hand, accelerating increases speed and that can easily lead a bike to become LESS stable, particularly as you push unreasonable lean angles such as your suggested 40 degrees. For example, the restoring force tries to change your direction of travel into a straight line. It grows with speed.
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Mikeydude
Male Advanced Member
741 Posts
[Mentor]


Ft. Worth, Texas
USA

Harley-Davidson

03 FXD Super Glide

Posted - 06/15/2011 :  10:28 PM
I think I missed something... You increase traction by accelerating?
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James R. Davis
Male Administrator
17282 Posts
[Mentor]


Houston, TX
USA

Honda

GoldWing 1500

Posted - 06/15/2011 :  10:36 PM Follow poster on Twitter  Join poster on Facebook as Friend  
quote:
Originally posted by Mikeydude

I think I missed something... You increase traction by accelerating?


Only when you are in a curve. You know that traction is a function of weight carried by the tire and that you feel heavier when pushed into your seat while making a turn. Accelerating in a curve increases centrifugal force. Centrifugal force and gravity are orthogonal (perpendicular) so the combination of both is a vectored total that is greater than either, but not as great as their sum - pushing in the direction of your lean angle.

Even then, however, while traction is increasing, so, too, is the demand on traction so it is essentially a wash except for the net gain you get by virtue of the fact that curves are invariably banked.
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rider5
Male Starting Member
4 Posts


Melbourne
Australia

BMW

R1100GS

Posted - 06/15/2011 :  11:03 PM
Thanks James, if I've got this right, the myth is that increasing traction IS the same as increasing stability. I'm with you 100% stable is stable. IMO - KC in advocating an increase in speed to increase traction is looking for a net gain in acceleration whereas Roadcraft is simply looking for stability and therefore a stable platform. I think.
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(Deleted or Lost)

Posted - 06/16/2011 :  2:58 AM
quote:
I suppose I kind of get the issue of increasing traction by accelerating gently, which is exactly what Roadcraft recommends in order to maintain speed. Would I be right in thinking that as you tip and lean and therefore lose speed, by opening the throttle you compensate and therefore get a weight transfer?


Rob, you're still not seeing a vital point.

If you increase engine speed as you tip in (in order to account for cornering losses) and the result is that your corner entry speed is maintained, then there hasn't been any acceleration. That is the whole point.

The engine revs have increased, but the bike hasn't accelerated. The bike's speed has been maintained and has remained constant - which is the stated goal of the roadcraft manual, i.e., NO acceleration.

That IS NOT what KC advocates. KC advocates an initial amount of throttle at tip in (he calls it "cracking on") to account for cornering losses and then consciously, evenly and gradually rolling on more throttle so that the bike's speed increases throughout the corner (- which results in some weight transfer rearward). This throttle control is also what Lee Parks advocates. Clearly this is NOT what the roadcraft manual advocates.


As can be seen from the articles, gentle acceleration increases the available traction (and yes the demand on traction - so it must be said this increase has a limit) and KC and Lee Parks say that this also increases "stability" as well (perhaps not the official definition of stability) - so clearly then a constant speed cornering picture doesn't give maximum traction and stability as stated in the roadcraft manual. If you don't agree, please point out where the logic in this post doesn't hold together.

That's NOT to say that this is an unstable or poor traction picture, far from it, just NOT the MAXIMUM as claimed by the roadcraft manual. That's what I've pointed out is the error.



To quote Lee Parks: "Next time you go riding, try the same corner both while coasting through it and while being on the gas. The difference in chassis stability will seem like the difference between night and day." That's not a track based comment.


Edited by - Robsalvv on 06/16/2011 3:02 AM
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rayg50
Male Moderator
2082 Posts
[Mentor]


NYC, NY
USA

Honda

Shadow Spirit 750DC

Posted - 06/16/2011 :  6:01 AM
quote:
try the same corner both while coasting through it and while being on the gas


I read the quote differently. IMO

Coasting = no additional throttle

Being on the gas = additional throttle

So the way I interpret it is that if you increase throttle on a curve it will feel different (more stable) versus just letting momentum carry you through.

I do not derive from that quote the conclusion (which he may state elsewhere) that the goal is to result in an increased speed rather than just maintaining your entry speed.

I guess I am missing the point. If I am already made stable by maintaining speed (minor rolling on) where is the benefit in seeking to increase speed? I see where it would get me through the turn faster. I do not see where coming closer to limits would get me through the turn safer.

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dhalen32
Male Moderator
841 Posts
[Mentor]


Omaha, NE
USA

BMW

R1200RT

Posted - 06/16/2011 :  6:36 AM
quote:
Originally posted by James R. Davis

This is what I referred to:
quote:
The "roll" step of the slow, look, press and roll process described in MSF courses is intended to stabilize the motorcycle's suspension and maintain ground clearance for cornering


So,
quote:
Do not chop the throttle while leaning in the curve as this reduces your ground clearance at the worst possible time.

is a restatement of what I objected to, but it remains incorrect even as restated.

Reducing speed in a curve stands a bike taller and, thus, increases ground clearance.

If you are too hot in a curve and begin dragging a peg, surely you would not advocate accelerating.

'Chopping' the throttle does, however, destabilize - something to be avoided while traveling in a curve.




Jim:
I'm sorry that I have not explained myself very well in this thread. When I have talked about ground clearance and stability in this discussion I meant, but should have stated, in a fore/aft or chassis pitch axis. As an Instructor of new students I have the pleasure of watching the effects of ham-handed application of brakes and throttle in a very close up manner during several cornering exercises in every class which I teach. I can see how the chassis pitches forward and backward as the student applies and releases the brakes or rolls the throttle off and on. I am also able to see how the bike's forks compress and extend as well as the rear swingarm moving up and down. These motions change the steering geometry and affect the overall stability of the motorcycle. With some training bikes' forward foot controls I can also see heels, toes and footpegs get close to scraping the ground or do so in extreme cases. Suspension settings and rider size are also factors in this fore and aft chassis and suspension movement.

However, you are absolutely correct that at lower cornering speeds lean angle must decrease and ground clearance will thus increase in the roll axis of the motorcycle.

I think that we both agree that the safest way around a corner is to apply only enough throttle to maintain one's speed, stabilizing the motorcycle in a smooth arcing path and then accelerating back up to the posted speed upon reaching the exit point of the corner.

I hope I got my perspective explained correctly this time! Sorry for the confusion.
Dave
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James R. Davis
Male Administrator
17282 Posts
[Mentor]


Houston, TX
USA

Honda

GoldWing 1500

Posted - 06/16/2011 :  8:26 AM Follow poster on Twitter  Join poster on Facebook as Friend  
Dave,

As I first said, there's no doubt that you know what really happens and that your statements were a misspeak.

I had nowhere near the experience you have in teaching MSF beginner classes but I well remember how I (and I assume most instructors) have repeated things so often that they become a catechism - rote repetition because they needed to be said that way every time. So it is not a surprise that in a different venue we tend to say those things exactly the same way again and not realize that we are talking about counter-steering, real-world, situations instead of slow speed, on-the-range, training. Our intentions are good and the information is good, except for that different venue.

Yep, you cleared it up. Thanks.
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James R. Davis
Male Administrator
17282 Posts
[Mentor]


Houston, TX
USA

Honda

GoldWing 1500

Posted - 06/16/2011 :  9:00 AM Follow poster on Twitter  Join poster on Facebook as Friend  
To make sure that all readers here are on the same page ...

This topic deals with whether or not accelerating (increasing speed) is safest when riding in a curve as compared to simply maintaining speed through the turn.

What this discussion is NOT about is 'coasting' through a curve.

Maintaining speed REQUIRES a powered motorcycle - then engine driving the rear wheel. Coasting is a non-powered maneuver in which, because of drag, the motorcycle DECELERATES (unless it is going down hill).
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(Deleted or Lost)

Posted - 06/16/2011 :  6:07 PM
quote:
Originally posted by rayg50

quote:
try the same corner both while coasting through it and while being on the gas


I read the quote differently. IMO

Coasting = no additional throttle

Being on the gas = additional throttle

So the way I interpret it is that if you increase throttle on a curve it will feel different (more stable) versus just letting momentum carry you through.

I do not derive from that quote the conclusion (which he may state elsewhere) that the goal is to result in an increased speed rather than just maintaining your entry speed.

I guess I am missing the point. If I am already made stable by maintaining speed (minor rolling on) where is the benefit in seeking to increase speed? I see where it would get me through the turn faster. I do not see where coming closer to limits would get me through the turn safer.



Ray, you may be right about the context of coasting. Lee Parks is definitely talking about accelerating through a corner though. His throttle exercise is the same as Calafornia Superbike School, which is a continuous roll on throughout the corner providing gentle acceleration.

If Lee Parks is comparing a zero throttle coasting (and decelerating as James points out) trip through a corner versus a powered one, it will indeed be like night and day!


I take your point about being stable with constant speed and at the risk of repeating myself, I understand and know that it is NOT an unstable or poor traction scenario.

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