Author Topic: Covering the Front Brake  (Read 5549 times)

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Offline Hogboy

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Covering the Front Brake
« on: November 03, 2011, 12:53:01 am »
Still amazes me that many an "instructor" believes this is a dangerous technique to teach to newbies, especially in town.

Saves 117 feet (1/3 football field) @ 80 mph  http://www.motorcycle.com/rider-safety/knowing-how-to-brake-saves-the-most-lives-88119.html

“I’ve worked with police departments to reduce their accident rates. One key is to encourage motor officers to always cover the front brake lever. In some police training programs, any officer who is caught riding without covering the front brake lever must pay a $5 “donation” to a benevolent fund. Getting them into the habit of always covering the front brake has resulted in measurable reductions in accidents.”  - Hurt Report
« Last Edit: November 03, 2011, 12:54:39 am by Hogboy »
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Offline Ranger Jim

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Re: Covering the Front Brake
« Reply #1 on: November 03, 2011, 11:06:43 am »
MSF RiderCoaches discourage it for newbies because:
  1.  We/they are (typically) operating at relatively slow speeds.
  2.  They (typically) do not have the concept of brake modulation ingrained in their minds.

As all of us more experienced riders know; grabbing a big handful of front brakes at slow speeds is one of the best ways to get your CDA.

I tell my classes that as they get more experience they need to begin to cover the controls (as is discussed in one of the videos we present to them). 

Hope this explains it.
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Offline wild man

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Re: Covering the Front Brake
« Reply #2 on: November 03, 2011, 11:23:08 am »
Jim
I'm thinking if they’re that new maybe they shouldn’t be on the street yet?  Have them gain some experience with a dual sport bike off-road, say on county roads or abandoned parking lots, before they even entertain the notion of mixing it up with traffic.  Brake awareness should be a prerequisite to the beginner class

Riding coverless would scare the bejebers out of me

The article was a good read.
« Last Edit: November 03, 2011, 11:26:01 am by wild man »
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Offline Hogboy

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Re: Covering the Front Brake
« Reply #3 on: November 03, 2011, 11:33:11 am »
MSF RiderCoaches discourage it for newbies because:
  1.  We/they are (typically) operating at relatively slow speeds.
  2.  They (typically) do not have the concept of brake modulation ingrained in their minds.

As all of us more experienced riders know; grabbing a big handful of front brakes at slow speeds is one of the best ways to get your CDA.

I tell my classes that as they get more experience they need to begin to cover the controls (as is discussed in one of the videos we present to them). 

Hope this explains it.
Jim, I can understand this logic but agree with Wild Man that they aren't ready for the street if they're not ready to cover.  Terrifies me to see some newbies who simply take the starter course, get their licence and never improve from there (i.e. covering, counter-steering, practice locking up, etc.).

Also agree with his comments about dirt riding, although I recognize that it may be more difficult now than it was when I was a young hippie.  We'd throw knobbies on our little street piddlers and get out in the nearby bush rain or shine.

You learn pretty quick here about slides, fr/rear brake, poor traction, etc.  You also learn naturally to cover your front when racing and buddy carves you up.
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Offline Cap'n Bob

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Re: Covering the Front Brake
« Reply #4 on: November 03, 2011, 11:45:53 am »
 I'm not so sure it's only taught to newbies. The Connecticut experienced rider course also stresses not ever covering the front brake. Well at least it was stressed in the class I took. Now to be fair, maybe they were only trying to stress it at low speed maneuvers. Which I have try not to keep my finger on the brake lever. But the impression I got was that it was never a good idea to cover the brake. (maybe I am not totally correct on the policy and Steve will have some input here)
 Although I since try not to cover in slow maneuvers because of what possibly could happen. (but that doesn't mean someone might not grab the front brake and dump the bike anyway) But I see where there is less chance of grabbing it. But I totally disagree with this on the road (not slow speed). I have always and will continue to cover the front brake most of the time. My reaction time in emergency is much faster than being a five fingers on the grip. There is no proof and convincing me otherwise.

Offline Hogboy

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Re: Covering the Front Brake
« Reply #5 on: November 03, 2011, 01:33:47 pm »
This is from Art Friedman in consultation with Harry Hurt (Hurt Report).  Art is a founding member of the MSF and ex-editor of the brilliant Motorcyclist magazine.

Myth #2:
You Should Only Brake with All Four Fingers on the Lever


"When I took my MSF class, the instructors said I shouldn't cover the front brake unless I'm preparing to stop, and the only way to fully control the front brake is to use all four fingers." While this may be true for beginners in a MSF course, riders should learn how to cover the front brake once they've moved beyond basic operational skills. We'll get to the how in a moment. First, the why.

As a rider rolls down the road practicing SIPDE, the concept taught by MSF (see Survival, August 2000), the time between when he notices a hazard that must be responded to and the moment of the actual physical response is called Reaction Time. Common sense says that if the rider's fingers are already covering the front brake, the Reaction Time will be shorter than if he has his fingers curled around the throttle. Since (as former Motorcycle Cruiser editor Art Friedman is fond of pointing out), the realities of motorcycling often don't follow common sense (as in countersteering), the Head Protection Research Laboratory, a think tank formed by Dr. Harry Hurt (author of the famed Hurt Report in the early 1980s), conducted a study entitled Hand Position and Motorcycle Front Brake Response Time. The study concluded:

"The human factors approach [to preventing motorcycle accidents] begins with education of motorcyclists to the value of covering the critical front brake. Training and practice in the effective use of the front brake and covering the brake lever has the potential to increase the numbers of motorcyclists who successfully avoid a critical violation of their right of way."

Your comfort level in properly controlling the throttle and the front brake will play a major role in your ability to cover the lever. If you're unsure of your throttle and braking technique, take a MSF class. When covering the front brake, try various numbers of fingers until you find out what works best for you. Some people prefer to use all four fingers, while I generally use two with the remainder giving me a firm grip on the throttle. Before you actually ride on the street, sit in your driveway and practice rolling the throttle on and off while covering the brake. If you have trouble closing the throttle completely, release it and place your hand on the grip with your fingers resting on the brake lever. Then, wrap your fingers around the grip and try opening and closing the throttle. Next, roll off and apply the front brake. The motion should be as smooth as possible. If the lever traps your fingers against the grip when you apply the brake, try adjusting the lever or bleeding the brake line. If the problem remains, you will need to cover the lever with four fingers. Once you feel comfortable closing the throttle and braking simultaneously, try it in a parking lot and then move to the street.

While you might struggle initially with this new throttle control and braking technique, don't be disheartened. Remember how long it took for releasing the clutch from a stop to become second nature? I spent two months riding with the front brake covered before it became automatic. Your investment will pay dividends every time you face a panic-stop situation. Once you've mastered the covering technique, you'll discover you can also smooth your entry into corners by beginning to roll on the throttle while you are still releasing the brake. As you spend time focusing on the front brake, don't forget that covering your rear brake will also shorten your reaction time.

The beauty of motorcycling comes from refining your skills each time you ride. So, take a step up the learning curve and learn to cover your front brake.

Read more: http://www.motorcyclecruiser.com/streetsurvival/advanced_braking/index.html#ixzz1ceWwjwUS
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Offline BigJoeVA68

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Re: Covering the Front Brake
« Reply #6 on: November 03, 2011, 03:14:46 pm »
A side benefit for me when I started covering the levers was less hand numbness. I actually find it more comfortable...
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Offline Rev Ryder

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Re: Covering the Front Brake
« Reply #7 on: November 03, 2011, 07:39:26 pm »
I generally do not cover the clutch, but always cover te brake with at least two fingers.  I may alternate between two and four for comfort, but I really only need two fingers to haul the bike to a stop quickly.  When I had stock C-10 brakes it took a BIG handful to get stuff happening.  The new, big radial calipers and 320mm discs make 1 finger stops possible (though two is really much better for emergency braking).

I learned to cover the brakes when fourteen years old and getting my first license in Kansas.  That's been over 40 years and I doubt I could NOT cover the brakes without having to think about it for it to happen.  I think MSF should teach it at all levels, but that's just me talking cuz I learned it early... I learned it long before I learned the countersteer lesson.
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Offline Gypsy JR

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Re: Covering the Front Brake
« Reply #8 on: November 07, 2011, 05:52:19 pm »
I cover the brake and clutch on my ZX14 when I'm riding in a situation where I may have to brake fast. Or if I just feel like doing it to relax my hands some.

I do most of my braking with 2-3 fingers, with some either 1 or 4. I've just learned the ZX14 well enough that my brake hand automatically grabs as hard as it has too.

Oh, does the C14 have a slipper clutch ?
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Offline kathybrj

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Re: Covering the Front Brake
« Reply #9 on: November 15, 2011, 06:55:45 pm »
My beginner MSF course taught to cover the clutch, not the brake. They put us through our paces with locking up the rear brake and I've had instances where having that bit of training came in handy.  Speaking with others that have taken courses over the years it seems what is taught is not uniform across the board.
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Offline Dalroo

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Re: Covering the Front Brake
« Reply #10 on: November 15, 2011, 07:55:37 pm »
It may be the old dirt bike rider in me, but covering the front brake is something I have always done. It just feels natural.

Another habit that has served me well so far (knock on wood) is when I see a cager who might possibly turn in front of me, and unsure if he or she sees me, I will actually engage the brake lightly, first to get that nanosecond headstart on braking, but also so those behind me see my brake light illuminate. Many of you probably have the same experiences, but personally, I have had MANY situations where I've thought to myself, "That car is about to pull out in front of me," and they actually do. Based on a previous accident, my biggest concern when riding in traffic is that I may have to stop quicker than someone behind me can react. If my brake light get's me noticed a critical second earlier, it can only help.

Not to get on a long rant on riding safety, but it always bugs me to see motorcyclists tailgating for the same reason as above. Yes, perhaps they can stop in time if the vehicle in front of them suddenly brakes, but by tailgating, they've eliminated the ability to perform evasive maneuvering. They are also putting themselves in a position where they may be forces to stop quicker than following traffic. Again, I can tell you from first hand experience, even in a car getting rear ended on a freeway can really jack up your day.

As in anything, it is the one you don't see that get's you, but that doesn't mean I quit paying attention to those I can avoid.
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Offline S Smith

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Re: Covering the Front Brake
« Reply #11 on: November 15, 2011, 08:20:41 pm »
I cover the brake and clutch on my ZX14 when I'm riding in a situation where I may have to brake fast.

IIRC MSF states this somewhere in the course material... that covering the brake is suggested when the need to brake fast may be needed, like in traffic, etc.  This is not a technique taught, as it is easily learned/adopted by riders.  The curriculum focuses instead on methods to develop good [braking] techniques. 

The Hurt Report implies that rider skill absence in braking, swerving, and cornering techniques (among others) was a significant contributing factor in the cause of crashes.  Having coached riders for over 10 years I have witnessed these weak riding skills in experienced riders. I've observed that many sport and adventure touring riders tend not to fall in this category.

Here are a few of the other top issues identified by the Hurt Report...

Quote
Approximately one-fourth of these motorcycle accidents were single vehicle accidents involving the motorcycle colliding with the roadway or some fixed object in the environment.

In the single vehicle accidents, motorcycle rider error was present as the accident precipitating factor in about two-thirds of the cases, with the typical error being a slideout and fall due to overbraking or running wide on a curve due to excess speed or under-cornering.

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Offline 2linby

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Re: Covering the Front Brake
« Reply #12 on: November 15, 2011, 11:14:04 pm »
My beginner MSF course taught to cover the clutch, not the brake. They put us through our paces with locking up the rear brake and I've had instances where having that bit of training came in handy.  Speaking with others that have taken courses over the years it seems what is taught is not uniform across the board.

I believe Steve covered the ciriculla taught through MSF in regards to use of the front brake and I do beleive the technique is consistant throughout all MSF classes. In Oregon I teach the same method through Team Oregon.

I think any confusion in regards to the training of beginning motorcyclists covering the front brake has already been addressed. However to clarify, the technique of NOT covering the front brake or for that matter the rear brake during any time other than preparing to and moving through intersections, is taught to reduce the high probability of aggressive overbraking on the front and the subsequent loss of traction resulting (ususally) in a low side collision.

Basically beginning riders do not have the experience or have not had enough time to develop the proper technique of being smooth AND progressive (NOT abrupt) with the front brake. As we all know this takes dedicated practice and in time they will develop a higher proficiency in this skill. In the three day 15 hour course for beginners we have enough time to emphasis and allow them to practive the technique of smooth and progressive use of the front brake. Unfortunatley we do not have enough time to get all of them proficient at it. Thus the reason for not covering the front brake in all but the most critical multi vehicle travel areas, the intersection. 
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Offline kathybrj

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Re: Covering the Front Brake
« Reply #13 on: November 16, 2011, 10:28:45 am »
My beginner MSF course taught to cover the clutch, not the brake. They put us through our paces with locking up the rear brake and I've had instances where having that bit of training came in handy.  Speaking with others that have taken courses over the years it seems what is taught is not uniform across the board.

I believe Steve covered the ciriculla taught through MSF in regards to use of the front brake and I do beleive the technique is consistant throughout all MSF classes. In Oregon I teach the same method through Team Oregon.



It's interesting, though, that at the National this year I was speaking with several people that had taken the beginner MSF course in their home area and were taught to cover the brake in their classes (NOT the clutch), so I can't agree that the method "is consistent throughout all MSF classes". Even between the two locations where the classes are held here, near Albany, NY,  there are inconsistencies regarding this topic. My nephews took the course at the opposite location I took it and were taught to cover the brake and not the clutch. I'm not sure why there is such a discrepancy between the classes.

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Offline Boomer

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Re: Covering the Front Brake
« Reply #14 on: November 16, 2011, 11:34:37 am »
I cover both brakes and the clutch when lanesplitting or in a busy environment.
Too many times it has made the difference between a shouting match and an accident.
Just yesterday a dumb**** in an MPV decided to change lanes, without signaling, right into me.
I honked and braked and he looked and pulled back into his lane, then proceeded to get pissy.
I ignored him and took my turning about 2 miles later.

The dumb**** followed me all the way to a gas station.
In the gas station he got out of his car and came charging over to me.
He didn't look best pleased when I got off the bike and stood in front of him, all 6'4", 360lbs of me in armoured jacket, crash helmet and gloves with carbon knuckle protectors. I laughed and told him that maybe he could benefit from an anger management class.

Another technique when lanesplitting is to watch the cars FRONT WHEELS.
A car cannot turn sideways into you without first turning his wheels.

My final piece of wisdom applies in all circumstances.
ALWAYS HAVE AN ESCAPE ROUTE IN MIND!
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Offline Cap'n Bob

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Re: Covering the Front Brake
« Reply #15 on: November 16, 2011, 04:09:38 pm »
The dumb**** followed me all the way to a gas station.
In the gas station he got out of his car and came charging over to me.
He didn't look best pleased when I got off the bike and stood in front of him, all 6'4", 360lbs of me in armoured jacket, crash helmet and gloves with carbon knuckle protectors. I laughed and told him that maybe he could benefit from an anger management class.



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Offline 2linby

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Re: Covering the Front Brake
« Reply #16 on: November 16, 2011, 06:28:42 pm »

It's interesting, though, that at the National this year I was speaking with several people that had taken the beginner MSF course in their home area and were taught to cover the brake in their classes (NOT the clutch), so I can't agree that the method "is consistent throughout all MSF classes". Even between the two locations where the classes are held here, near Albany, NY,  there are inconsistencies regarding this topic. My nephews took the course at the opposite location I took it and were taught to cover the brake and not the clutch. I'm not sure why there is such a discrepancy between the classes.

I can guarantee the method is 100% consistant within Team Oregon Training and I would bet it is consistant with MSF classes as well. I think the confusion lies in the discussion with the students that in order to reduce reaction time (quicker response)  in hazardous situations (say an intersection full of other vehicles) you should temporarily cover the brakes and then return your hand back to the throttle/handgrip.

This is only one of several strategies discussed along with proper lane positioning to be seen and see, space cushioning and escape routes during the "mental motorcycling" portion of the class.

I bet if you go back to your classroom riders guide book and review what was covered there it'll be clear as to what was taught. In any case this is always a good thing to re-read and study and with winter on us well what else are ya gunna do!
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Offline Gypsy JR

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Re: Covering the Front Brake
« Reply #17 on: December 05, 2011, 12:43:05 pm »
Motorman (Ride Like a Pro) says to cover the front brake when you think you may have to stop suddenly.

He expects you to be bright enough to know when that is.
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Re: Covering the Front Brake
« Reply #18 on: December 05, 2011, 02:54:12 pm »
When I took the course as a refreasher after riding dirt for a few years I was amazed at how many people never use the front brakes....my instructor was very adament about covering the front brakes and using them correctly . In all vehicles that's where your stopping power comes from .
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Offline Gypsy JR

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Re: Covering the Front Brake
« Reply #19 on: December 05, 2011, 07:32:03 pm »
Yes, most stopping power comes from the front brakes, no matter bike or car. When you slow the weight transfer loads the front tire(s) which means they get more grip, while the rear tire(s) lose traction because they are unweighted.

This is why, in a panic stop, you slam on both front and rear brakes completely. It doesn't matter if the rear brake locks up and slides, you will maintain steering in front, and if you keep your head level and your eyes down the road (not looking at the ground in front of you) you will stay straight and stop.

I remember decades ago the huge argument over this in rec.motorcycles, and just around then California Highway Patrol came out with a series of videos and studies (video on vhs, btw, way pre-DVD) which proved beyond a shadow of doubt that locking them both up yielded shortest stopping distance.

Now that we have electronic ABS and TC, the system can turn that max pedal and lever pressure into a concert and stop you even quicker.

But what CHP demonstrated in the 80s holds true. If you react quickly, and try to lock both front and rear up, ABS will know you want to stop fast and get it done.
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Offline smithr1

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Re: Covering the Front Brake
« Reply #20 on: December 05, 2011, 08:15:03 pm »
This is why, in a panic stop, you slam on both front and rear brakes completely. It doesn't matter if the rear brake locks up and slides, you will maintain steering in front, and if you keep your head level and your eyes down the road (not looking at the ground in front of you) you will stay straight and stop.
...
But what CHP demonstrated in the 80s holds true. If you react quickly, and try to lock both front and rear up, ABS will know you want to stop fast and get it done.

I am not so sure it is ever a good idea to lock the front up.  If the video showed that I would like to see it.
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Offline 2linby

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Re: Covering the Front Brake
« Reply #21 on: December 05, 2011, 08:49:08 pm »
Yes, most stopping power comes from the front brakes, no matter bike or car. When you slow the weight transfer loads the front tire(s) which means they get more grip, while the rear tire(s) lose traction because they are unweighted.

This is why, in a panic stop, you slam on both front and rear brakes completely. It doesn't matter if the rear brake locks up and slides, you will maintain steering in front, and if you keep your head level and your eyes down the road (not looking at the ground in front of you) you will stay straight and stop.


While this is true, however on pavement in almost every condition once the rear wheel is sliding AND is not in alignment with the front (directly behind it) you can NOT steer to control your direction. That is to say you are now totally committed to holding the bike upright in a straight line.

Quote
I remember decades ago the huge argument over this in rec.motorcycles, and just around then California Highway Patrol came out with a series of videos and studies (video on vhs, btw, way pre-DVD) which proved beyond a shadow of doubt that locking them both up yielded shortest stopping distance.

Now that we have electronic ABS and TC, the system can turn that max pedal and lever pressure into a concert and stop you even quicker.

But what CHP demonstrated in the 80s holds true. If you react quickly, and try to lock both front and rear up, ABS will know you want to stop fast and get it done.

The coefficenet of friction on a rollling tire is greater than that of a sliding/skidding tire.

Calculate the Stopping Distance of a Car with Locked Wheels

1) Determine the coefficient of friction between the tires and the road. If the wheels of the car are locked, the tires are sliding across the pavement and a kinetic coefficient of friction should be used. For tires in good condition and dry pavement, the coefficient of kinetic friction is approximately 0.7. Worn tires, wet roads, or ice can reduce the coefficient of kinetic friction.

2) Select an initial velocity for the car with units of feet-per-second. Speeds in MPH can be converted to feet-per-second by using this formula:

5280FT (feet in a mile) X MPH (your speed) / 3600  (5280 x 60MPH) = 316,800FPH/3600s (60 minutes* 60 seconds) =88FPS

Another Example: 5280FT (feet in a mile) X 75MPH / 3600  (5280 x 75MPH) = 396,000FPH/3600s =110FPS

3) Calculate the stopping distance of a car using the following formula: D = V2/μg, where V is the starting speed of the car in feet/sec, μ is the coefficient of kinetic friction between the tires and the road, and g is the acceleration due to gravity. For example, a car traveling at 88 ft/sec (60 mph) on a dry road with good tires will require (88 ft/sec)2/(2 * 0.7 * 32 ft/sec/sec) = 172 feet.


Now Calculate the Stopping Distance of a Car with Rolling Wheels

1) Determine the coefficient of friction between the tires and the road. If the wheels of the car are turning, the tires are rolling on the pavement, and not sliding as in the locked wheels example. In this case, a static coefficient of friction should be used. For tires in good condition and dry pavement, the coefficient of static friction is approximately 1.0. Worn tires, wet roads, or ice can reduce the coefficient of static friction.

2) Select an initial velocity for the car with units of feet-per-second. Speeds in MPH can be converted to feet-per-second by using this formula:

5280FT (feet in a mile) X MPH (your speed) / 3600  (5280 x 60MPH) = 316,800FPH/3600s (60 minutes* 60 seconds) =88FPS

3) Calculate the stopping distance of a car using the following formula: D = V2/μg, where V is the starting speed of the car in feet/sec, μ is the coefficient of static friction between the tires and the road, and g is the acceleration due to gravity. For example, a car traveling at 88 ft/sec (60 mph) on a dry road with good tires will require (88 ft/sec)2/(2 * 1.0 * 32 ft/sec/sec) = 121 feet.

It can also be assumed the coefficient of friction of a motorcycle tire in both cases and in most cases would be slightly greater than that of car tires.

You have more control and shorter stopping distances when you do not skid your tires.
« Last Edit: December 06, 2011, 08:31:31 pm by 2linby »
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Offline Centex

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Re: Covering the Front Brake
« Reply #22 on: December 05, 2011, 10:06:11 pm »
"You have more control and shorter stopping distances when you do not skid your tires."  -  2linby

^^^ +++1,000 ^^^

Science works .... at this scale, the laws of physics, motion and teh characteristics of friction are well established.



To say that CHP demonstrated skidding tires stop shorter than a rolling tire, while also saying that ABS, (which is solely designed to maximize braking force short of tire skid) does better, is inherently contradictory (both statements cannot be true, all other factors being equal).   :-[
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Offline Gypsy JR

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Re: Covering the Front Brake
« Reply #23 on: December 06, 2011, 01:10:16 pm »
Agree, which is why you have ABS. Not you, nor Casey Stoner, nor anyone here is good enough to attenuate braking pressure in a panic stop. MotoGP riders regularily throw their bikes off the track because they can't control it perfectly.

Applied to a motorcycle, it is nearly impossible to lock the front tire up in a panic stop. Maybe in the last 10 feet. By then it doesn't matter.

I've done dozens of full boat both brakes max pressure stops on MSF and other courses on my ZX14. The rear tire locks up easy. But if you keep your head up and eyes front, focused where you want to be when you stop, the bike does not slide laterally. If you panic, you get a tail whipper.

I have only managed to lock the front tire up when I slowed enough (under 15 mph)  and did it on purpose. Its called a stoppie. You have to let go of the brake lever, what goes up must come down. Heh.

I cannot stop the ZX14 faster by trying to imperfectly attenuate braking pressure.

I'm guessing my C14 will not stop in a shorter distance than I can do with my ZX14. But close. And it will be easier, letting the ABS handle it.
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Offline S Smith

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Re: Covering the Front Brake
« Reply #24 on: December 06, 2011, 01:44:17 pm »
ABS should be used as a tool to improve the safety margin and minimize risk, but not replace correct braking skills. I think most, if not all, motorcycle safety training programs advocate the philosophy of learning and practicing proper braking skills. MSF defines the term Maximum Braking as "full application of both brakes without locking wither wheel."  I take this to mean threshold braking just before the point of ABS activation and should result in the shortest possible braking distances.  I feel this is a skill that anyone can learn and master for typical street use.  I have practiced Max Braking on the C14 and have yet to have the ABS activate. I still need to push it a bit more, as I would like to have a better feeling how the bike will react when ABS does kick in if I hit a patch of sand or wet pavement.

As a side note... When we first started seeing riders with ABS in ERCs around here, another instructor notice how so many were relying on the ABS for max braking that he said it was an acronym for "Absence of Braking Skills."
 





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