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pmdave

Braking Practice

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pmdave

It might be helpful to less experienced riders to review some techniques for practicing braking. Based on the history of previous attempts to address this, I suggest we be more respectful than usual of other rider's viewpoints.

 

pmdave

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pmdave

Braking practice is intended to help a rider learn the correct techniques, so that in day-to-day riding they can be practiced. In an emergency, we tend to revert back to whatever we've been practicing.

 

If it's not obvious, in a real-world impending crash, we won't have the luxury of knowing when and where we'll need to stop. So, when approaching a potentially risky situation (say an oncoming car that could turn left across your path) you'll have both the correct braking technique, and the "muscle memory" to squeeze the lever.

 

Let's back up a bit to aggressive straight-line stops, as practiced over the years in various training courses. The idea is to bring the bike to a complete stop in the shortest possible distance.

 

Since the machine and rider at speed have inertia (some folks call this "momentum") braking depends upon tire traction to overcome this forward energy.

 

Since the combined center of mass of bike and rider is somewhere in the vicinity of the rider's knees, and the braking traction is applied down at ground level, the result of hard braking is that the bike wants to loop forward over the front tire contact patch. Most standard machines and cruisers are heavy enough that a complete forward loop is not likely, but the point is that under braking the forward energy causes more weight to be loaded on the front tire.

 

Since traction is a function of weight on the tire, more stopping force can be applied to the front tire as weight "tansfers forward" during an aggressive stop.

 

So, here's the first practice drill: set up a straight "braking chute" on clean, dry, level pavement, with lots of clearance around. The braking chute should be at least 100 feet long, with another 50 feet of runout at the end. One easy way to mark this is with tennis balls cut in half.

 

Ride down the braking chute at an initial speed no faster than 20 mph. At the braking point, simultaneously roll off the throttle, squeeze the clutch, and progressively squeeze the front brake lever and apply the rear pedal. Keep the bike vertical, your eyes up, and your feet on the pegs.

 

As the bike comes to a stop, keep your right foot on the rear brake pedal, shift down to first gear, and stop with your left foot supporting the bike. Think about your stop, note the distance, then return to the start of the chute for the next run.

 

When you are able to stop the bike from 20 mph without skidding either tire, bump your approach speed to 22, then 24 mph. As your approach speed is increased, the bike will behave differently, so it's smart to ensure you have the technique down before increasing speed.

 

More to follow.

 

pmdave

 

 

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pmdave

Is it acceptable to skid the tires during an aggressive stop--assuming a machine without Anti-lock brakes (ABS)?

 

You can't skid the front tire very far before losing control of balance, so a front wheel skid shoud be avoided. If the front tire does start to skid, ease up on the lever to regain traction.

 

The danger with skidding the rear tire is that if the sliding rear end goes out to one side, the natural reaction is to release the pedal, which causes a sudden snap back to center that can flip the rider off the bike. This is called a "high side" because the bike flips from the low side to the side that was higher. If it's not obvious, a high side flip can be very dangerous. So, it's best not to skid either tire during an aggressive stop.

 

There is another reason for not skidding the tires. Maximum traction occurs at about 15% slip. Once the tire begins to slide, traction decreases--which lengthens the stop. And if the brakes aren't applied hard enough, that lengthens the stop. So, the ideal is to apply the brakes aggressively, but just short of skidding either tire. That's not easy, but it can be mastered with practice.

 

Quick stop practice is much easier with an ABS-equipped bike, because the ABS computer will make it almost impossible to brake so hard you skid the tires. However, there are lots of situations other than straight line stops, so it's smart to practice the same basic braking techniques regardless of the brake system.

 

pmdave

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David

Good stuff, Dave. Especially your point about "reverting to training under pressure."

 

I'll offer a tip about body positioning. It's critical to stay loose on the bars under heaving braking. Otherwise, you're fighting the bike's suspension and the contact patch is going to be compromised.

 

Under heavy braking, though, it's easy to arrest the natural forward movement of your body by holding yourself back with your arms.

 

The tip: squeeze your legs together against the tank instead. In fact, you can push back on the pegs a little, but it's mainly your inner thigh pressure.

 

Thanks for starting the thread!

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pmdave

Let's back up a moment to the instant of squeezing the brake lever. It's important to squeeze the lever as quickly as possible in order to shorten stopping distance, but it's also important to squeeze progressively harder during the time when weight is transferring to the front tire.

 

When practicing, one suggestion is to squeeze harder over one second, as you say out loud, "one-thousand-and-one." As you gain proficiency in squeezing the lever, you can shorten that time, so long as it is a progressive, not an instant squeeze.

 

For straight line quick stop practice, it's best to roll the throttle closed as you apply the brakes, and to squeeze the clutch lever fully. That removes engine braking from the equation, so that all braking is via the lever and pedal.

 

Since you are practicing skills to be used in the real world, it's a good habit to check your mirrors as you bring the bike to a stop. Since you've shifted down into first gear, if you see a following vehicle not stopping quickly enough, you can get the bike moving quickly into an escape path.

 

pmdave

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pmdave

If your machine is not ABS, you must depend on some feedback to let you know when you are approaching a skid.

 

If steering begins to feel vague, that's an indication the front tire is approaching a skid. Of course, you'll be holding your body from being flung forward, so you'll get a "seat of the pants" measure of the stopping force. You may also hear the tires growling or howling, meaning they are very close to sliding.

 

You'll find that the front tire gets easier to skid during the last few feet of the stop. That's because as forward energy is scrubbed off, the force pressing down on the front tire is reduced slightly.

 

Some veteran riders find a longer braking area, and practice stops from as high as 60 mph, to get the maximum practice time out of each stop. The risk for an inexperienced rider is that the kinetic energy of a machine moving at 60 mph is high enough to cause severe injury if the techniques aren't exactly right. The best approach to practicing braking is to start at a very low approach speed and gradually bump up speed as you gain skill and confidence.

 

It's not practical to attempt quick stops on busy public roads, because drivers around you won't understand what you're doing. However, you can practice on a vacant road in the country.

 

What's really important is to use all of the practice techniques during every stop, even when you're just coming to a normal stop. In an emergency you'll most likely revert to those habits.

 

pmdave

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pmdave

You may have seen braking charts in new bike magazine tests, and formed some opinions about how quickly a certain bike can be stopped. Those tests are a good indication of the power of a given brake system, but are not realistic for real world emergency stops.

 

Note that test riders' stops are measured by radar, so the bike begins the stop at the instant the rider applies the brakes. In the real word, there will be a reaction time while the rider's brain is processing the hazard, and during that reaction time the bike continues forward at the same speed.

 

Reaction time for a very quick rider is around 0.5 sec. For an average touring rider, reaction time might be 0.75 sec. And for an older, fatigued, or preoccupied rider, reaction time might be a full second or longer.

 

Test riders also get good tires, level pavement, good weather, and several stopping attempts to get the shortest time. In the real world, you might not have any of those advantages, and you only get one attempt to get it right. That's why it's important to keep more space around you, to cover the front brake lever, and to look for escape routes.

 

pmdave

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cpallen

Excellent! Thank you for posting.

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russell_bynum

Disclaimer: All of this comes from what I learned from Dick Frantz. As far as I know, he developed this material and these drills, himself. I want to give credit where credit is due.

 

 

1. Riding Position:

 

Start with the Master Yoda Riding Position

This gives you a good foundation from which to build the rest of your skills.

 

 

2. Ideally you would do these drills with ABS disabled or on a bike without ABS.

 

Threshold braking:

Get up to about 30-35 mph and apply a small amount of rear brake pressure (remember to build up over about 1 second). Ride that to a stop. Go around again and apply a bit more pressure...just a bit more than before. Ride that to a stop. Repeat. Eventually you'll get to the point where the rear brake will lock. Keep it locked and just ride the skid to a stop. Repeat that, and practice applying a bit of countersteering (carefully/gradually) to see how you can make the rear come out to one side or the other....just a little at a time at first. Remember to keep your upper body loose and grip the bike with your feet against the pegs and knees on the tank) Then come around again, and apply the same amount of brake force to get the rear locked. As soon as you detect that it is locked, remove one increment of brake pressure. The rear will regain traction gently. Ride that to a stop. Repeat until you're comfortable with that.

 

What you're doing, is you're learning how to modulate the brake so that if you lose traction and a wheel locks, you don't freak out...you just remove a bit of pressure, regain traction, and continue on with your day.

 

Next start with the front brake. 30-35mph. Add a bit of front brake pressure (build up over the course of a second). Ride it to a stop. Keep going again and again, adding more and more pressure each time until you get the front to lock. As soon as it does, release one increment of pressure and you'll regain traction. Don't try to ride a locked front wheel to a stop...that won't end well. :grin:

 

 

If your bike has ABS that can not be disabled, do the drills, but instead of taking the wheels to the point of lockup, take them to the point of ABS engagement. Ideally, you would be able to learn these skills first without ABS getting in the way and then enable ABS (or switch to a bike with ABS) and see how ABS changes things.

 

 

 

3. You've got two brakes for a reason!

 

Don't neglect the rear brake. While it is true that the front brake gives you most of your stopping power, that doesn't tell the whole story. The rear brake can do quite a bit...especially on a long bike which have a fair amount of weight over the rear wheel, like most BMW's. As you incease overall brake pressure, the front becomes more and more effective and the rear becomes less effective due to the forward weight transfer. But...when you first start braking, the rear can do quite a bit....and you haven't transfered the weight forward yet, so the front is not as effective. The answer is to use both brakes, and to lead with the rear brake.

 

to visualize how this works, say "ta-DUMMMMMMMM-ta". "ta" is the rear brake, and "DUM" is the front.

 

ta-DUMMMMMMMMMM-ta:

When you want to apply the brakes, start with the rear and follow it shortly with the front. "ta-DUM". As you apply more overall brake pressure, you will need to tansition more of that pressure to the front, and less to the rear because the bike's weight transfers off the rear and onto the front. Eventually you'll be at the point where you have little/no rear brake pressure and full pressure up front. Then, as you complete the stop, you revert back to the rear brake....reducing overall pressure and transitioning off the front and applying more rear until you come to a stop with little/no front brake and all the pressure on the rear.

 

 

This technique takes full advantage of the fact that the rear brake is quite effective initially....you really want to maximize the stopping power you've got, so don't neglect the rear. Transitioning back to the rear brake towards the end of the stop will bring you to a nice smooth stop without upsetting the front suspension with an abrupt rebound like you get if you stop using only the front brake.

 

 

 

The three things I just described was the basis for the braking seminars that Dick used to do. We would start around 8am with a half-dozen or so riders and by lunchtime, everyone was able to do the drills comfortably.

 

From there, it just takes practice...repetition to build muscle memory and replace your natural "Survival Reactions" (which are usually counter-productive in the context of riding a motorcycle) with something more productive.

 

Next up: braking in a corner.

 

 

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motorman587

Why can we not just let a post be a post and say good job, thanks for posting. Everybody throws in their $02 worth, makes it confusing.

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motorman587
It might be helpful to less experienced riders to review some techniques for practicing braking. Based on the history of previous attempts to address this, I suggest we be more respectful than usual of other rider's viewpoints.

 

pmdave

 

Good luck on that one, on this site!!! You will be beaten down.

but good post. Sound like motorcop or MSF trained. I am being called in as expert witness in a motorcycle crash (civil side) and the issue is braking on the motorcycle part. It is hard/explain to tell non-unskilled riders that there is "a lot" going on to smoothly effectively stop a motorcycle.

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russell_bynum
Why can we not just let a post be a post and say good job, thanks for posting. Everybody throws in their $02 worth, makes it confusing.

 

I thought the purpose of this was to talk about what we do for braking practice. If I'm mistaken and this was just supposed to be Mr. Hough's thread, then I sincerely apologize and I'll start a new thread for my braking ideas.

 

David....what say you?

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yabadabapal

Now I know what I didnt know before. Great explanation and technique.

We beginners need more. Whenever your ready.

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ShovelStrokeEd

I'm in full agreement with Russell. What he posted is about the technique for good braking and development of the skills. What could be more appropriate a place for this than a discussion about braking practice.

 

I, and others, use exactly this technique for ALL my braking, whether for emergency stopping or just puttering around the street. David has emphasized the need for practice so that, when the excrement hits the rotary air distribution device, you will automatically do what you have trained yourself to do.

 

It's great to go out on the range and find the limits of what you and the motorcycle can do. It is, by far, the safest place to do so. However, if you confine your practice to the range and then use other techniques out in the world, you will negate all that you have learned. Develop your technique and then reinforce the training by using the technique on EVERY stop. See the first line of my sig

Edited by ShovelStrokeEd
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tallman

As explained to me.

Just for clarity.

 

Inertia is the measure of how much resistance matter has to acceleration. The more inertia something has, the less it wants to respond to forces and accelerate. This statement is mathematically stated a = F/m. newtons s second law.

 

m is the measure of inertia, called (inertial) mass. the more force, the more acceleration. the more inertia, the less acceleration.

 

Momentum is the product of inerta (m) and velocity (v). p=ma. It turns out that momentum is always conserved in any closed system. Momentum is related to inertia, the more inertia something has, the more momentum it has, when in motion.

 

You can think of momentum as the ability to exert a force for a time. That product, Ft is called impulse. The amount of impulse a body is able to exert is exactly the same as the amount of momentum it has.

 

Practice is usually a good thing to do.

Don't forget to do it in bad weather too.

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Dick_at_Lake_Tahoe_NV

Thanks Dave, I found your practice suggestions so helpful, I copied/pasted them all into a Word-document I'll share with my grandson who is just starting to ride. Good Stuff.

Dick

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Groanup

Thanks Dave.

I also made a copy of your posts. I practice emergency braking, but now I have a better method to follow.

Thanks to you too Russel, especially for point #3. I am guilty of neglecting my rear brake and now know why I shouldn't.

 

Good stuff gents.

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markgoodrich

John, I thought Dave wanted input, at least, that's the way I interpreted his initial post.

 

Reg Pridmore's CLASS school has a section on just this issue, smooth, accurate braking. He differs from pmdave's comments (and others) only in insisting that the rider not pull the clutch lever until the very last second. Easier said than done, since most riders (me, anyway) have decades of riding doing exactly the opposite, pulling the clutch lever in while hitting the brakes.

 

Freddie Spencer's school (and presumably now Nick Ienatsch's) teaches "don't touch the rear brake" for the majority of the curriculum, adding rear braking after students have mastered other skills such as trail braking, smooth downshifting, etc. The importance of the rear brake is emphasized in the school, the technique taught being to aim for 10% braking at the rear. Mind you, that's not panic braking to avoid hitting the skunk, it's braking to hit the apex, but still....

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russell_bynum

Freddie Spencer's school (and presumably now Nick Ienatsch's) teaches "don't touch the rear brake" for the majority of the curriculum, adding rear braking after students have mastered other skills such as trail braking, smooth downshifting, etc. The importance of the rear brake is emphasized in the school, the technique taught being to aim for 10% braking at the rear. Mind you, that's not panic braking to avoid hitting the skunk, it's braking to hit the apex, but still....

 

Another thing to consider is that Freddie's school is more race-oriented and all of the students ride sportbikes (Last I heard, the school had CBR600RR's that everyone rode.) Rear brake is much less useful on a sportbike since they tend to put much more weight bias on the front wheel and the forward weight transfer is more severe due to the short wheelbase.

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pmdave

When riding on slick surfaces (rainy day) or when carrying a passenger, your braking technique will be different.

 

On a surface with less traction, there will be less weight transfer to the front. That means you can use more rear brake to approach the ideal 15% slip. If it's really slick (say spilled diesel oil or black ice) you should apply both brakes very gently, with roughly 50/50 rear/front bias. If you attempt to apply too much front brake, the tire may lose traction before there is much weight transfer.

 

When carrying a passenger, there will be much more weight on the rear wheel, which translates to much more traction than when riding solo. You might find that braking bias can be around 40/60 rear/front even during an aggressive stop.

 

However, during an aggressive stop with a passenger, you are attempting to declerate the bike while the passenger's mass wants to keep going. So, as you brake harder, the passenger will slam into the rider's back, pushing the rider forward. And as the rider feels he/she is unable to hold position on the saddle, that dictates how much braking can be applied. IOW, you don't squeeze the lever any harder, to avoid being pushed up on the tank. It doesn't make much difference what sort of brake system you have in this situation, because the limiting factor is how well you are able to hold rider and passenger in position.

 

If you regularly carry a passenger ("second rider") you can prepare for an aggressive stop by doing the braking practice with a passenger. This will give the passenger some exposure to the forces involved. And perhaps the passenger can find a better way to brace for braking. My suggestion would be to do the braking practice solo, then repeat the drills with passenger.

 

We might also note that if you aren't as skilled as your self image, you can screw up and dump the bike. In the past, I did a few braking clinics, and also taught the ("old") ERC. It was not unusual for a veteran rider to approach the brake marker too fast on the first drill, then dump the bike. So, I suggest wearing your gear. And, just as with cornering, it's easier to go in slow at first and then incrementally jack up the speed as you gain skill and confidence.

 

pmdave

 

 

 

 

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pmdave

The main reason for avoiding the rear brake is that a machine with a short wheelbase and a relatively high CoM (think sport bike here) can do a stoppie much more easily. A cruiser or standard (think H-D or ST here) has a much longer wheelbase, so there will be more weight farther behind the front CP. That means a cruiser is much less likely to do a stoppie.

 

So, if you're riding a short-wheelbase sport machine with very powerful front brakes, you need to be very proficient at controlling not only skids, but also rear wheel liftoff. Once the rear tire is airborne, it can't provide any lateral stability, and the rear end can suddenly try to pass the front. I'm not kidding here, I've seen it happen.

 

Whether ABS will help manage stoppies depends on the system. In general, the rider will need to modulate (the Germans cal this "dosing") the brake lever to keep the rear tire more-or-less on the ground.

 

Let's also note that hills will change the equation. Uphill is no problem. Downhill can be a big problem, because the down-slope pull of gravity is added to the forward energy, and since kinetic energy increases rapidly with increases in speed, it's possible to approach a downhill corner or intersection so fast that you just can't reduce speed.

 

pmdave

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TyTass

Thanks to all, but especially the points on how riding 2up changes braking (which I kinda already "knew" from experience ... I ride 2up a lot).

 

I need to practice more with these lessons in mind ... especially 2up.

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pmdave

Before we move on from straight-line braking, let's consider how the throttle relates to the brakes.

 

When you roll off the gas at speed, the engine stops turning the rear wheel. Instead, the rear wheel tries to turn the engine. So, on a trailing throttle the engine serves as a brake. But remember that compression braking only acts on the rear wheel.

 

A rider may not appreciate that during a quick stop, with the engine already braking the rear wheel, dabbing on the rear brake may exceed available traction and cause a rear wheel slideout.

 

Let's also note that ABS can't control engine compression braking, although there are some traction control systems now on the market that will help avoid a rear wheel slideout in such situations.

 

So, in a quick stop, the advice is to just squeeze the clutch and keep engine braking out of the equation. But more serious riders who use engine braking as a habit may prefer to transition from throttle to brakes.

 

"Transition" means a smooth transfer from engine power to brake power, not two separate actions. I believe that throttle-to-brake transitions are very important to braking while in corners, and it's a skill you can practice first in a straight line.

 

Find some empty road somewhere. With the bike at say, 50 mph, smoothly roll the throttle closed while simultaneously easing on the front brake. Do not squeeze the clutch or shift. As the bike decelerates to say, 30 mph, transition back to throttle. Ease off the front brake as you sneak the throttle back on. Let the bike accelerate back to speed, then repeat.

 

Not so coincidentally, this is one of the exercises in Lee Park's Total Control course. Lack of skill in throttle-brake transitions relates to single vehicle crashes in corners.

 

You'll have to figure out how to manipulate the throttle and brake lever simultaneously. You can either grip the throttle with your three outer fingers and thumb, or grip the throttle with your index finger and thumb. The other fingers control the brake lever.

 

Many riders use the first two fingers on the brake lever. That's OK for machines with powerful brakes, but requires very accurate control of the lever because the force is being applied very close to the lever pivot.

 

Other riders prefer braking with the three outer fingers, which requires less muscle pressure and provides more accurate lever control. Use the finger positions that work best for you and your machine.

 

Let's also note that it's just as important to transition smoothly from brake to throttle, because popping off the brake tends to unload the front wheel and reduce traction. Again, this must be controlled by the rider, since the brake system can't modulate a sudden release of the lever. A rider could be braking nicely in a sharp curve, then pop loose of the lever, and slide out the front tire.

 

pmdave

 

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pmdave

After you have practiced straight line braking and throttle-brake transitions without and then with a passenger, it's time to consider braking in corners.

 

Riders who have taken a basic rider course have typically been told to avoid braking in turns. But real world situations will eventually spring a hazard on you while in the middle of a turn. So, you may need to do an aggressive stop while leaned over.

 

Obviously, if you overbrake on either wheel while leaned over, you'll crash. So, the trick is to be able to brake right up to the limits of whatever traction you have in reserve at the moment. Over the years we have taught two different techniques. One is to ease on the brakes while still turning, and then swap cornering traction for braking traction as the bike slows. The other technique is to immediately lift the bike to vertical and do a straight line stop within the roadway you have left.

 

The second technique has proven to stop the bike in the shortest distance, and also gives ABS the advantage.

 

However, your riding style determines which technique you'll have to use. If you ride at a relaxed pace, the "lift it up and brake in a straight line" technique should get you stopped without running out of pavement.

 

But, if you are riding at an aggressive pace, there won't be enough pavement to stop in a straight line. So, the faster you ride, the more important it is to be very skillful at braking while leaned over. If you have honed your throttle-brake transitions, you should be able to use the brakes while leaned over--without sliding out.

 

The practice for quick stops in curves is to find some big parking lot somewhere and set out some cones to make a circle. First, try the "lift it up and stop in a straight line" technique. This will be smoother and easier if you transition quickly to the brake, but it's OK to just squeeze the clutch and focus on modulating the brake lever.

 

Now, practice braking while leaned. Definitely, transition smoothly to the brake, then ease on more brake as the bike decelerates and lifts up. The tail end of the stop will be the same as a straight line stop.

 

Practice both techniques in both directions, and if you normally ride with a passenger, follow up by doing both exercises while carrying the passenger.

 

If you're an old hand at all this, just remember to practice once a year, especially if you don't ride during the winter months. If this is new turf to you, work up your speeds gradually. In any case, wear your crash costume in case it doesn't work out as planned.

 

You will probably find it helpful to do your brake practice in company with one or two other riders. You can trade off, watching what happens, and noting that to the practicing rider. You can also have one rider signal the stop (raising outstretched arms horizontal) to add some reality to the practice.

 

pmdave

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Ken H.
"Transition" means a smooth transfer from engine power to brake power, not two separate actions. I believe that throttle-to-brake transitions are very important to braking while in corners, and it's a skill you can practice first in a straight line.

 

Find some empty road somewhere. With the bike at say, 50 mph, smoothly roll the throttle closed while simultaneously easing on the front brake. Do not squeeze the clutch or shift. As the bike decelerates to say, 30 mph, transition back to throttle. Ease off the front brake as you sneak the throttle back on. Let the bike accelerate back to speed, then repeat.

 

Not so coincidentally, this is one of the exercises in Lee Park's Total Control course. Lack of skill in throttle-brake transitions relates to single vehicle crashes in corners.

Yes, I’ve taken Park’s course and during the braking training exercised they emphasized throttle/brake control to avoid nose dive and rear tire unloading. At the far end of the particular braking course of the moment a person was positioned to watch for headlight dip during your braking. The goal was no dip, no nose dive at all. Controlling your throttle roll off to brake applying to maintain max traction both front and back was the point being emphasized. Two tires in optimized contact are better than one. Which in some cases would actually mean releasing some front brake, which was very counterintuitive and hard to get yourself to do. But the proof was in the measured stopping distances which were much better with the controlled dive approach. I was skeptical at first that releasing some braking could actually shorten my stopping distances, but came away convinced.

 

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pmdave

I believe what the psych researchers say--that in an emergency a human will take immediate action (fight or flight) and think consciosly about the situation later.

 

It appears that what we will do in a surprise situation is based on our habits. I believe that's true of emergency situations while riding. When a hazard suddenly appears, it's likely you'll do whatever you usually do in that riding situation.

 

If that's true (and I believe it is) then let's imagine a situation where you are approaching a busy intersection with cars that could potentially pull into your path. If you are in the habit of controlling speed primarily with just the throttle, then your subconscious response to a driver turning across your path will likely be to just roll off the throttle.

 

On the other hand, if you are in the habit of easing on the front brake as you approach all intersections, you will most likely respond to a car in your way by squeezing on more front brake.

 

So, with regard to the above, I suggest that there aren't really any special "emergency" maneuvers you need practicing. What's really important is to practice the right stuff all the time when you ride. That includes not just covering the brake lever and practicing smooth throttle/brake transitions, but constantly searching the situation ahead for potential hazards, and adjusting the situation early enough that you never have to respond in a hurry.

 

pmdave

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ShovelStrokeEd
I believe what the psych researchers say--that in an emergency a human will take immediate action (fight or flight) and think consciosly about the situation later.

 

It appears that what we will do in a surprise situation is based on our habits. I believe that's true of emergency situations while riding. When a hazard suddenly appears, it's likely you'll do whatever you usually do in that riding situation.

 

If that's true (and I believe it is) then let's imagine a situation where you are approaching a busy intersection with cars that could potentially pull into your path. If you are in the habit of controlling speed primarily with just the throttle, then your subconscious response to a driver turning across your path will likely be to just roll off the throttle.

 

On the other hand, if you are in the habit of easing on the front brake as you approach all intersections, you will most likely respond to a car in your way by squeezing on more front brake.

 

So, with regard to the above, I suggest that there aren't really any special "emergency" maneuvers you need practicing. What's really important is to practice the right stuff all the time when you ride. That includes not just covering the brake lever and practicing smooth throttle/brake transitions, but constantly searching the situation ahead for potential hazards, and adjusting the situation early enough that you never have to respond in a hurry.

 

pmdave

 

Print that and paste it to the underside of your windscreen, guys and gals. If you can't fit it all, do the last paragraph at least.

Edited by ShovelStrokeEd

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russell_bynum
I believe what the psych researchers say--that in an emergency a human will take immediate action (fight or flight) and think consciosly about the situation later.

 

It appears that what we will do in a surprise situation is based on our habits. I believe that's true of emergency situations while riding. When a hazard suddenly appears, it's likely you'll do whatever you usually do in that riding situation.

 

If that's true (and I believe it is) then let's imagine a situation where you are approaching a busy intersection with cars that could potentially pull into your path. If you are in the habit of controlling speed primarily with just the throttle, then your subconscious response to a driver turning across your path will likely be to just roll off the throttle.

 

On the other hand, if you are in the habit of easing on the front brake as you approach all intersections, you will most likely respond to a car in your way by squeezing on more front brake.

 

So, with regard to the above, I suggest that there aren't really any special "emergency" maneuvers you need practicing. What's really important is to practice the right stuff all the time when you ride. That includes not just covering the brake lever and practicing smooth throttle/brake transitions, but constantly searching the situation ahead for potential hazards, and adjusting the situation early enough that you never have to respond in a hurry.

 

pmdave

 

Print that and paste it to the underside of your windscreen, guys and gals.

 

Yup. That's the best thing I've seen in a long time.

 

 

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dhanson

Very good info here for all. I have had many close calls in my years of riding, most brought on by my aggressive riding in traffic.

 

I agree that we will do what we practice mostly. I have never experienced the frozen digits of panic they speak of, always had control to do what I normally do, but did have to clean my pants out later.

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Ken H.
So, with regard to the above, I suggest that there aren't really any special "emergency" maneuvers you need practicing. What's really important is to practice the right stuff all the time when you ride. That includes not just covering the brake lever and practicing smooth throttle/brake transitions, but constantly searching the situation ahead for potential hazards, and adjusting the situation early enough that you never have to respond in a hurry.

Well I agree, that’s quite right. You can’t teach yourself an emergency response. You can only teach yourself a response that you will use in an emergency.

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markgoodrich

Dave, thanks a million for all your comments here, and thanks to all the others who had constructive input.

 

Given that most of us ride BMWs, and so many BMWs and other brands now have linked brakes, with varying degrees of pressure applied to front/rear, do you have any differnt suggestions for linked vs not-linked braking technique?

 

 

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russell_bynum
Dave, thanks a million for all your comments here, and thanks to all the others who had constructive input.

 

Given that most of us ride BMWs, and so many BMWs and other brands now have linked brakes, with varying degrees of pressure applied to front/rear, do you have any differnt suggestions for linked vs not-linked braking technique?

 

 

My advice is ignore the linking and brake as if your bike didn't have it because:

1. That technique will work if you have a bike with some variation of linked brakes.

2. It will also work if you someday ride a bike without linked brakes.

 

You could be lazy and just use the front brake lever, and let linking worry about the back, but why intentionally develop a bad habit that you may someday have to force yourself to unlearn?

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tallman

One point not mentioned yet, WRT to braking.

 

Slow down.

Ride a bit slower.

You cover less ground per second, you stop quicker from a lower speed.

Possibly less chance for bad outcome if you do brake incorrectly.

 

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smiller
My advice is ignore the linking and brake as if your bike didn't have it because:

1. That technique will work if you have a bike with some variation of linked brakes.

2. It will also work if you someday ride a bike without linked brakes.

 

You could be lazy and just use the front brake lever, and let linking worry about the back, but why intentionally develop a bad habit that you may someday have to force yourself to unlearn?

I agree with this sentiment and it represents the only thing I don't like about the servo/integral braking system on the newer R & K bikes. The system works very well but if you use the rear brake you can often feel the system alternating between your control input and that generated by the bike, with the end result being the feeling that by providing manual input you're only mucking things up. And in most cases you are as the bike does a very good job of things, but when I go back to my 1100RT I then have to re-adapt to using a 'normal' rear brake. I'm still not sure what to make of it all. The integral system is a technical tour de force in terms of performance but I have mixed feelings about how it changes the way I ride.

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russell_bynum
My advice is ignore the linking and brake as if your bike didn't have it because:

1. That technique will work if you have a bike with some variation of linked brakes.

2. It will also work if you someday ride a bike without linked brakes.

 

You could be lazy and just use the front brake lever, and let linking worry about the back, but why intentionally develop a bad habit that you may someday have to force yourself to unlearn?

I agree with this sentiment and it represents the only thing I don't like about the servo/integral braking system on the newer R & K bikes. The system works very well but if you use the rear brake you can often feel the system alternating between your control input and that generated by the bike, with the end result being the feeling that by providing manual input you're only mucking things up. And in most cases you are as the bike does a very good job of things, but when I go back to my 1100RT I then have to re-adapt to using a 'normal' rear brake. I'm still not sure what to make of it all. The integral system is a technical tour de force in terms of performance but I have mixed feelings about how it changes the way I ride.

 

That's good to know. I have no interest in a system that requires developing bad habits.

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smiller
That's good to know. I have no interest in a system that requires developing bad habits.

Well I guess that kind of depends on the situation. For an experienced rider with multiple bikes then yes, front brake only is a pretty bad habit. OTOH for someone who only owns one bike and isn't of the mind to frequently practice max braking then the integral system could save their bacon one day. While I agree that 'grabbing a handful and praying' isn't the optimal braking technique no matter how much computer-controlled gee-gaw there is behind it, my impression is that even if you do select that technique the latest integral system will stop you somewhere bewteen 90-110% as well as an expert rider. In the real world I'm not convinced that's necessarily a crazy trade-off... hence my mixed feelings.

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russell_bynum
That's good to know. I have no interest in a system that requires developing bad habits.

Well I guess that kind of depends on the situation. For an experienced rider with multiple bikes then yes, front brake only is a pretty bad habit. OTOH for someone who only owns one bike and isn't of the mind to frequently practice max braking then the integral system could save their bacon one day. While I agree that 'grabbing a handful and praying' isn't the optimal braking technique no matter how much computer-controlled gee-gaw there is behind it, my impression is that even if you do select that technique the latest integral system will stop you somewhere bewteen 90-110% as well as an expert rider. In the real world I'm not convinced that's necessarily a crazy trade-off... hence my mixed feelings.

 

I don't dispute that bad technique might work acceptably on bike A, today, if all the gadgets and gee-gaws are working properly and you're within their design spec. But what about when you're on a different bike? (I've got six in the garage and never turn down an offer to ride a different bike.) What about when the gadgets and gee-gaws fail? (It isn't a common thing, but we've definitely seen all manner of failures with ABS over the years.) What about when you're operating outside of the system's design parameters?

 

I shouldn't judge the new system yet since I haven't had a chance to play with it. But I'm a big believer that all of this technology should just work quietly in the background. If it gets in the way or makes me do something stupid in order to get the most out of the system, I'm not a fan.

 

 

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smiller
I shouldn't judge the new system yet since I haven't had a chance to play with it. But I'm a big believer that all of this technology should just work quietly in the background. If it gets in the way or makes me do something stupid in order to get the most out of the system, I'm not a fan.

Well there's the rub I guess. The system is fairly unobtrusive for the most part, but you can definitely tell it's there. In some ways that's an inherent part of the design, i.e. if I get off the rear brake too soon and the system thinks/knows that I need more then it's going to apply it... unless there is some algorithm that says 'Seth just got off the rear brake and that must have been intentional so he must not really want the integral system to do anything for the time being' and I can see how that wouldn't be very practical to implement, or at least until such time as technology progresses to where I can sit down with the braking computer and discuss my riding preferences and philosophy :grin:.

 

Seriously, it may be possible to further refine the system to make it more transparent (subject to the limitation I mentioned above) but in practical terms there will probably always be some interaction between the rider's inputs and the computer's inputs. I suppose one simple solution would be to allow the rider to simply turn it all off if desired but I can see why that might have some very negative performance implications for a safety system of this sort.

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Paul Mihalka

Let's keep in mind that this discussion is going on between very experienced technically oriented riders, like Russell, Ken H, SMiller, Tallman, and others. That is not the majority of riders, not even BMW riders. Most of my customers ride 3.000 to 4.000 miles a year at most, probably will never do any braking practice in a parking lot, and some of them still have to be convinced that a front brake stops you better than the rear brake and won't pitch you off. They will probably never ride a bike except their own. To these the best advice I can give is to grab a handfull, whether normal braking or emergency. On front to rear only linkage bikes use the rear brake for parking lots, U turns or down hill on gravel. For some of them coming from the Harley world (metric cruiser riders do better) the fully linked system from R1150RT or K1200LT was best. Step on pedal, and surprise, the bike stops.

FWIW this is what I see in real life.

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russell_bynum
Let's keep in mind that this discussion is going on between very experienced technically oriented riders, like Russell, Ken H, SMiller, Tallman, and others. That is not the majority of riders, not even BMW riders. Most of my customers ride 3.000 to 4.000 miles a year at most, probably will never do any braking practice in a parking lot, and some of them still have to be convinced that a front brake stops you better than the rear brake and won't pitch you off. They will probably never ride a bike except their own. To these the best advice I can give is to grab a handfull, whether normal braking or emergency. On front to rear only linkage bikes use the rear brake for parking lots, U turns or down hill on gravel. For some of them coming from the Harley world (metric cruiser riders do better) the fully linked system from R1150RT or K1200LT was best. Step on pedal, and surprise, the bike stops.

FWIW this is what I see in real life.

 

I know you're right, but that bothers me to no end. The whole "People are morons so lets make things moron-proof" mentality is one of the main factors which is slowly destroying this country. Why can't we raise the morons up to a higher level instead of bringing everything down to theirs?world>

 

 

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smiller
On front to rear only linkage bikes use the rear brake for parking lots, U turns or down hill on gravel.

That's a good observation in that the ability to isolate the rear brake with the BMW integral system is probably intended more to allow you to use the rear brake alone, not necessarily in conjunction with the front during normal stops from speed on pavement.

 

As to the rest I have to agree with you Paul. And I'll add that often with emergency braking the most important thing (again, average rider, most conditions) is getting on them soon, vs. nuances of technique.

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pmdave

tallman made an excellent point back there, about slowing down. My take on this is to slow whenever you are approaching a potentially hazardous situation. Scrubbing off just 10 mph from your normal arterial speed cuts actual braking distance almost in half.

 

Let's say you are approaching an alley with the nose of a car poking out, at a speed of 40 mph. If you transition to the front brake and slow just 10 mph to 30, you will be able to stop much quicker. Let's put some numbers to that theory:

 

Let's say you have a decent reaction time of 0.75 sec, and you are skilled enough (or your ABS is good enough) to pull a 30 sec per sec deceleration rate. Your reaction time would eat up 44 feet and your braking distance would be 57.5 or so. total: 101.5 ft.

 

Now, if you are already on the brake, your reaction time might be half--say 22 ft. And from 30 mph your braking distance would be say 32.5 feet. total: 54.5 ft.

 

You don't have to creep down the street all the time, just get on the brake when something looks fishy. If the car doesn't pull out, you can quickly get back up to speed.

 

pmdave

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pmdave

On the subject of linked and integrated brake systems:

 

I disliked the early power-assisted fully-linked ABS system BMW put on the (I think it was) 2001 RT. The brakes were way too sensitive, and just thinking about braking would slam on the brakes.

 

Since either the lever or the pedal would apply both front and rear brakes, you didn't dare dab on the rear brake to give the engine something to pull against when making a tight turn. And if you didn't keep the engine off idle, it tended to surge and stall while you were leaned over.

 

I found the "partially integrated" system much better. By then, the engineers had quietly detuned the power, so they felt almost like unpowered brakes. Plus, you could dab on the rear pedal and not dump the bike on it's side.

 

I haven't ridden the latest and greatest from the fatherland, so I can't comment on how the new "integrated" ABS performs. What they mean now by "integrated" is that the rear and front systems are hydraulically separate, but combined into a single control unit.

 

Since motorcycles are somewhat more difficult to maintain than cars, I prefer the unpowered, independent front-rear ABS approach.

 

pmdave

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pmdave

Linked brakes refer to hydraulically connecting the front and rear brakes in some manner. As I understand Honda's linked brake system, each caliper has several pistons, typically three. So, there's three pistons on the left caliper, three pistons on the right caliper, and three pistons on the rear caliper, or a total of 9 pistons. Each piston will produce about 33% of the braking force on that disc.

 

So, the front master cylinder is connected to two pistons on each front caliper, and one piston on the rear caliper. The rear brake master cylinder supplies two pistons on the rear caliper, and one each on the front calipers. That system provides proportional braking at about the amount needed for the typical situation.

 

If you are pulling off the road onto a gravel shoulder, dabbing on the rear brake does apply some braking to the front, but roughly the same as is being applied to the rear wheel. And, in an aggressive stop, adding rear pedal provides additional force to the front.

 

According to my sources, the Honda LBS also makes it easier to brake in corners, because braking bias rear/front is closer to weight bias rear/front.

 

When I first heard of the LBS I thought, "way too complex." But as it turns out, it's a lot easier to flush the fluids than to deal with bleeding a power system. So, in retrospect, I wish BMW had thought of the idea first.

 

pmdave

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smiller
When I first heard of the LBS I thought, "way too complex." But as it turns out, it's a lot easier to flush the fluids than to deal with bleeding a power system. So, in retrospect, I wish BMW had thought of the idea first.

I haven't ridden the Honda system but I'm not sure it's preferable to BMW's concept, which while being (much) more complex does have two rather big advantages. One, you can apply rear trailing brake and have no front brake action. This is what many riders prefer. And two, the BMW system can adaptively modulate the rear brake based on rider input and road conditions to apply an optimal (vs. preset) amount of rear brake.

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pmdave

Another issue we haven't discussed is how fatigue and other distractions relate to reaction time.

 

According to my source (a NHTSA guy who must remain anonymous), your reaction time is lengthened about 10% for several different issues, including age, mental distraction, and fatigue.

 

Many of us wear ear plugs to avoid hearing damage, but one of the advantages of plugs is reducing fatigue caused by noise. (primarily wind noise) Of course, fatigue is also a result of riding too long without taking appropriate breaks. That might explain why traveling riders tend to have crashes later in the day.

 

pmdave

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tallman

Daave,

A couple of other factors to consider.

Do you know how to determine how much brake pad you have remaining?

Many, many riders don't know how to tell this about their own bike, believe it or not.

Then there is the tire issue.

When braking, numbers tell one part of the equation.

But all the practice in the world can't put rubber back on a tire.

I change tires early.

Another little way to maintain an edge when it comes to removing speed rapidly.

I never want to have lack of tread become a factor in the equation.

 

Maintain the brake system, replace fluids.

Those are factors you can control.

Best wishes.

 

 

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ShovelStrokeEd

Amen on the slow down thing. A couple of years ago I posted about an experience with my 1100S where a small SUV turned left in front of me leading me to lock my front wheel (I didn't go down) and have to release brakes to take evasive action. It wasn't pretty and scared me $hitless. Sober reflection afterwords over a calming cup of coffee led me to conclude that the cause of the incident was ME. I was running about 50-52 in a 35 mph zone. Had I been going 35 or even 40, it would have been a non-event. I have since slowed quite a bit in an urban/suburban environment although I constantly have to remind myself to do so.

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markgoodrich

I recently read the results of a study done under controlled conditions regarding the effect of talking on a cell phone while driving. Bottom line: attention was reduced by 37% when using the phone (study was done using an active MRI or PET scanner, to watch the brain in action). That, by the way, is worse than being moderately drunk. I turn my cell phone completely off when I ride.

 

But, I do use an intercom, to talk to my wife, and do listen to music. So beware.

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pmdave

Mihalka has a good point here, that there are lots of riders who are not very skilled. Having a machine with "dumbed down" controls can help an unskilled rider manage an emergency situation. I've been told that the concept of "unskilled American riders" is what prompted Honda to put integrated brakes on the early Gold Wings.

 

However, in the long run I'd like to figure out how to get those unskilled riders a little more skilled. The motorcycle engineers can't make a bike foolproof. If the DA rider chooses to enter a busy intersection at twice the posted speed, no brake system in the world (short of retro rockets in the headlight shell) can save him/her.

 

Which gets us right back to the original idea of practicing aggressive braking. If what we have is acceptable to the experienced riders here, how could we motivate DA riders to actually get out and practice this stuff?

 

pmdave

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