Emergency Braking Article by Misti

[Misti]

In response to the "fishtailing" thread and some questions on proper braking here is an article I wrote for Motorcycle Mojo Magazine a few years back.

Stopping Fast!

I’ve seen it happen on more than one occasion, motorcyclists attempting to make an emergency stop making all sorts of detrimental errors. I’ve seen them lock up the rear tire severely and end up sliding across the pavement in an avoidable low side. I’ve seen them lock up the front tire, wobble dramatically from side to side and end up sliding across the pavement. I’ve seen people freeze, barely get on the brakes at all, and end up hitting the very thing they were trying to avoid. I’ve even witnessed a rider grab the front brake so hard and for so long that he rose up into a massive stoppie with the bike continuing to gain altitude until it was flipping over on top of him.

All of these errors are avoidable and with a little bit of rider education and training, emergency braking can become a well-learned and well-executed skill. It’s one of the things we coach at the California Superbike School during the two-day camp program, and something I’ve worked on with students in other rider training programs that I’ve been a part of.

Lets talk first about locking up the rear tire. It’s easy to do. It doesn’t take much pressure on the lever to get it to lock up and in most cases can cause unnecessary problems. With a locked up rear tire you lose valuable traction and the back end has a tendency to fish tail, or skid violently to one side or the other. Less pressure on the rear will help to prevent this from happening, and if you do lock it up, just let off the pressure gently until it is no longer locked. Don’t slam it on, and don’t chop it off.

Most riders have experienced to some degree the feeling of locking up the rear tire and are somewhat comfortable with it. Locking up the front wheel on a motorcycle however is much more elusive and therefore when it does happen can be one of the most terrifying parts of riding.

At the California Superbike School we have a bizarre looking motorcycle in the fleet of specialized training bikes, a Kawasaki Ninja 650R that has long yellow poles sticking out of the sides. The poles have small skateboard wheels on the ends of them and are designed to act a little bit like training wheels. They prevent the bike from tipping over, and crashing in a low-side and therefore provide extra confidence for students that are learning about emergency braking. The idea behind the Panic Brake Trainer, designed by Keith Code, is to allow students to experience a fully locked front wheel and then be trained to save it.

The exercise is to have the students get the bike into second gear, approximately 50km/hour and have them get on the front brake as if they were trying to avoid hitting something. From there we coach them on progressively pulling the front brake lever until the front wheel locks. When the front locks it often makes a loud chattering noise or skidding noise and sometimes a puff of smoke rises off the wheel. The tendency, when this happens to the rider, is to either let off the brakes completely which most often results in hitting the thing they were trying to avoid, or to keep the same amount of pressure on the brake lever, which continues the front wheel skid and usually results in a low side crash. Most have never felt this sensation before so they panic and don’t know what to do.

When our students finally lock up the front we coach them to come out of the brake a little bit, nice and gently, to the point where the front is no longer locked. This way, they continue to come to a stop but will no longer be testing traction with a locked front wheel. Most students find this exercise very valuable for two distinct reasons. One, they get to see how much pressure it takes on the lever to get the front to lock up, and two, they get to practice locking up the front and then saving it, without fear of crashing the bike. Most are surprised by just how much front brake they can apply without actually locking up the front tire.

Other things that will help make braking smooth and problem free include lever squeezing technique and body position on the bike. I usually recommend using two fingers on the front brake lever and pulling with smooth and progressive pressure. Avoid snatching the front brake or squeezing hard and fast at the end of braking. Also, avoid having super stiff or straight arms as you will transfer that pressure into the handlebars and can initiate a wobbling back and fourth that could turn into a tank slapper. Pinching the tank with your knees will help to keep the weight off your arms, and will also keep your body weight from sliding forward and putting too much weight on the front tire.

When you do find yourself in a situation of having to emergency brake, try to avoid target fixing on the object that you are trying not to hit. Focus on the braking and on seeing the available space around you that you could utilize. If you are able to brake safely and come to a complete stop then do so, if you think you are not able to brake hard enough to avoid the situation then you could brake hard to scrub off speed, release the brake completely and then quick steer around the problem. Don’t try to steer the bike with any amount of brake on.

Lastly, even though stoppies look cool, having the rear wheel in the air is not the safest way to come to a stop. A lot of people accidentally end up with the rear wheel lifting off the ground because they squeezed the brake lever harder at the end of their braking, almost like a little stab, and they let their entire body weight slide into the tank which puts too much weight forward, lightens the rear and results in a reverse wheelie. Squeezing the tank, relaxing the arms and pulling the brake in smoothly and evenly will help prevent this from happening.

This is one riding skill that can be practiced in a parking lot or empty side street. Start slowly and work on squeezing the brake lever smoothly and consistently and come to a complete stop. Then try to pull the lever a little harder and stop a little quicker. It pays to have at least practiced this skill a few times so that if you do suddenly find yourself in an emergency braking situation, you are better able to handle it.

Misti Hurst

[Alex]

Great info!

[JohnnyBravo]

Great info!!! Super bike school... Mmmmm

[backinthesaddleagain]

Thanks!

[alex.s]

Originally Posted by Misti

rear wheel lifting off the ground because they squeezed the brake lever harder at the end of their braking, almost like a little stab, and they let their entire body weight slide into the tank which puts too much weight forward, lightens the rear and results in a reverse wheelie. Squeezing the tank, relaxing the arms and pulling the brake in smoothly and evenly will help prevent this from happening.

thanks for your post misti! a few noobie questions for you;

do you think moving back on the seat before braking helps very much? do you do it? or is it so minor that its not worth the extra effort?
when you say squeezing the tank, i assume you're talking about when centered on the bike? when i find myself under heavy braking, its typically right before a turn so i'll already be off to the side of the bike... in this situation are you still squeezing the tank with both legs before letting the inside leg go? or just locked in with the outside leg into the tank and peg?
when dealing with the rear tire bouncing under heavy braking, once you're already there (provided it is just skipping/bouncing, not actually stoppying) would you simply ride the mess out and try to do better next time? would you actually go as far as reducing braking when the rear is just messy and not actually lifting much? assuming its not far out of line (nobody likes a highside, right?)

thanks again! love your posts.

[Misti]

Originally Posted by alex.s

thanks for your post misti! a few noobie questions for you;

do you think moving back on the seat before braking helps very much? do you do it? or is it so minor that its not worth the extra effort?
when you say squeezing the tank, i assume you're talking about when centered on the bike? when i find myself under heavy braking, its typically right before a turn so i'll already be off to the side of the bike... in this situation are you still squeezing the tank with both legs before letting the inside leg go? or just locked in with the outside leg into the tank and peg?
when dealing with the rear tire bouncing under heavy braking, once you're already there (provided it is just skipping/bouncing, not actually stoppying) would you simply ride the mess out and try to do better next time? would you actually go as far as reducing braking when the rear is just messy and not actually lifting much? assuming its not far out of line (nobody likes a highside, right?)

thanks again! love your posts.

Thanks!! Ok to answer your questions:

1. Do I think that moving back in the seat helps with braking? I think it's important to be in the right spot on the seat AT ALL TIMES and that exact spot will depend on how big you are, where your knee is pressing on the tank etc. In general, I think that sitting back a little farther in the seat (most people are right up agains the tank) helps to get you locked onto the bike better by getting your knee into the cut out of the tank better. I'm small and I'd say I'm in the middle of the seat, at all times.

2. Squeezing the tank: You and most riders will find it hard under heavy braking to stay back in the seat. The combination of setting up for the upcoming turn and already being off to the side of the bike and braking hard will tend to force the rider to slide forward into the tank. So, what I do is set my body position nice and early by hanging my butt off to the side BUT, I squeeze the tank with BOTH knees until I tip into the corner. This helps prevent me from sliding forward into the tank, which keeps extra weight off the arms, which keeps the bike handling better, etc.....

3. What do I do when the rear starts bouncing around: Depends on how bad it's bouncing. If it's a little wheel hop and skip or it's off the ground a little then I'd probably just ride it out. However, if I start going in full stoppie mode (and it's happened at a few hard braking corners- turn 2 at Laguna, turn 6 at Mid Ohio...) then I'll let off the brake just enough to get the wheel back on the ground or the skipping to subside a little. It's all about being smooth. Smooth getting on the brakes, smooth getting off the brakes. You can still grab the brakes hard and fast while being smooth.

Does that answer your questions?

[alex.s]

yes! thank you!

[nickjpass]

I read that all....

[drac]

I know I wasn't suppose to post here anymore but I do check in from time to time...... and just couldn't help myself.

I just wanted clarification on something................

Are you saying that at the Kieth Code school they teach emergency braking using the rear brake............ and do you, Misti Hurst, advocate using the rear brake during emergency stops?? It appears that way from the article.


Lastly.................. Did Alex actually post "Great info"???

WOW!!!!!

[nickjpass]

Not sure if @$$hole, trolling, or both?

[FvnnyL3tt3r1ng]

This thread will help fine tune my stoppies. Thanks misti!

[Alex]

Drac - you remain a thread-killing tool. You can return to lurking at this point. Here's a link for the clarification you seek.

Originally Posted by Misti

I personally use front brake only when riding a sportbike under almost all situations UNLESS I end up off the road or in a big patch of gravel or something and then I use the rear. I sometimes use both brakes at the same time if I'm cruising on the street and casually stopping at a stop sign or light or on the side of the road. Most of the time when riding and slowing for corners or in an emergency braking situation I use front only, the front brake on sportbikes these days are powerful enough to be used for 100% of the stopping power.

At the Suprbike school we teach emergency braking and we coach our students to use the front only (on sportbikes) as it is not as easy to lock up as the rear. Many riders panic in emergency braking situations and hammer on the rear causing it to lock up, skid and fishtale often resulting in a crash.

We coach students to apply the front brake smoothly, progressively and hard enough to be able to come to a quick stop but not hard enough to suddenly lock the front tire. We have a training bike with outriggers that prevent the bike from crashing and we purposely get the students to intentionally lock the front (which takes a lot more force and effort than most riders realize) and then we teach them how to release the pressure enough so that the front unlocks but they still come to a quick stop. From there we get them comfortable with braking just at the verge of locking the front which results in the quickest and safest stops with the least stopping distance. This can be practiced in a parking lot as well without a special training bike just be sure to work up to max braking safely and slowly.

We have also tested riders at our military school where we measure the stopping distance when they use both brakes vs using front brake only and the majority of students (after being coached on how to properly use the front for emergency braking) have a better stopping distance when they use front only because they didn't skid the rear and they weren't distracted by fear of locking up the rear.

Cruisers or bikes with less powerful front brakes will require use of both brakes at the same time in order to bring them to a safe and effective stop.

Misti

[ally99]

Thanks Alex. What an asshole.

[Motofool]

Originally Posted by drac

...........It appears that way from the article............

If you carefully re-read the article, you will disagree with your statement, Drac.

You can use either brake or both.
As you may know, traction is proportional to weight on the tire.
Braking capability of a vertical tire is proportional to its traction, which will change with road conditions (dry, sand, wet).

While the rider is understanding that he needs to stop in an emergency and reaches for the controls, the bike is not slowing down; hence, there is more weight on the rear tire than on the front.
In that state, the rear tire carries 60% of the total weight and has maximum traction while the front tire carries 40% of the weight.

Once the throttle is closed and one or both brakes are smoothly applied, deceleration starts happening, which increases the % of the total weight on the front and reduces the % of the weight on the rear, more for more violent deceleration.

For that reason the braking capability of the front tire increases while the braking capability of the rear tire decreases: time to reduce or eliminate all pressure from the rear caliper.
At the same time, the front caliper can and should be fed with more pressure progresively.

When the rear tire is barely touching the road, the % of weight on the front contact patch is around 95% Remember that it was carrying only 40% before start braking?, ......well, now it can brake more than twice harder without sliding !!!
Note that excessive initial pressure would have ruined that increment in braking power, making the front tire slip while carrying only 40~50% of the weight.

Coming back to your question:
Rear brake is good for initiating the weight transfer and for when you have a passenger, although its power weakens for high rates of deceleration.
Front brake is good and it gets more powerful as weight is transferred upon that tire and for high rates of deceleration.

For slipping road conditions, the front brake cannot reach full power without sliding and losing steering and balance.
Deceleration rate then cannot be so big and some good % of weight remains on the rear tire as to make the rear tire useful enough for those conditions.

As you can see, the laws of Physics together with personal preferences don't leave room for hard rules about this.

CSS coaches for racers and trackers, who seldom have to do emergency stops; hence, training focuses on smooth and precise braking for setting ideal entry speeds.

.......Yes, Alex, alex.s and many other members have been posting excellent and helpful information during your absence.

[alex.s]

{blush}

hernan said i was helpful!

[Motofool]

Originally Posted by alex.s

{blush}

hernan said i was helpful!

Yes, I have learned many things from yours, Misti's and others posts.

I could learn from lurkers too, .............. but they don't post !!!

[csmith12]

Originally Posted by Misti

2. Squeezing the tank: You and most riders will find it hard under heavy braking to stay back in the seat. The combination of setting up for the upcoming turn and already being off to the side of the bike and braking hard will tend to force the rider to slide forward into the tank. So, what I do is set my body position nice and early by hanging my butt off to the side BUT, I squeeze the tank with BOTH knees until I tip into the corner. This helps prevent me from sliding forward into the tank, which keeps extra weight off the arms, which keeps the bike handling better, etc.....

Great stuff Misti!

Maybe others can learn from my mistakes as well. If you get your bum off the seat while still on the gas, locking on with both knees while slightly hung off feels odd at first but it gets better with practice. It's also feels very, very odd if your hanging off too much. What's too much? It's too much when you can't get a good lock any longer, simple as that.

[CycleCam303]

Off topic but is there anything glaringly wrong with sitting close up to the tank? Don't get me wrong I'm king of body English. Though I'm pretty sure I hang off the ninja 250 with my crotch touching the tank. I'm super short and my legs. D arms aren't very long. When I'm up on the tank I can keep a bend in my elbows, be relaxed, along with having lots of leverage.

It's not that I can't be farther away, it's simply more comfortable when pushing the limits.

[csmith12]

Try this Cameron (bike on stands);
Sit all the way against the back of the seat with your knees on the tank and try to move your bum off. Where is your knees? Still on the tank?

Now...
Sit all the way forward on the seat and slide off. Where is your knees? Still on the tank?

Still think it's wrong? Does it matter? I will say "perhaps not". You will find many pro riders where their outside knee looses it's locked under the lip position while mid-corner. Why is this? Maybe they get off the seat to much or maybe they don't, perhaps the lil ninja is narrow for their physical size or all or some combination of all. Either way, they make it work in their own way, every riders "sweet spot" on the seat is different. As long as your position on the bike allows for complete control of steering (and other inputs), relaxed grip on the bars, uses your body mass to assist with minimizing lean angle and is comfortable, then it's all good in my book.

Could it be your background on the dirt bikes has influenced your preferred position on the ninja? Assuming you could improve on your position, could you separate your seating preferences from other bikes to NOT influence what could be better position on the ninja? Assuming your ninja has stock bits, how would more aggressive clipons and rearsets affect your seating preferences? Food for thought.

[CycleCam303]

It's really hard to tell on if I'm being honest when the bike is on the stand. When up on the tank my thigh is the only thing locking me in. Maybe I do sit in the middle of the seat to keep my knee in the slot.

I have stock foot pegs and that absolutely is one of the reasons I do sit up close. When my butt is touching the passenger seat my legs are bent at a 90 degree angle. My knee cap is the only thing on the tank and it doesn't feel secure at all. When getting on it hard out of a corner I think I compensate for the stock ergos by getting close to the tank so I can use the pegs to fight the forward g's. I don't have to hang on with my arms at all.

A good illustration would be I could ride a stock ergo r6 all day.

I'll have to go on a ride and think about where I am.

[alex.s]

stock rearsets? ...why?

[CycleCam303]

Originally Posted by alex.s

stock rearsets? ...why?

I know I know.

Why can't you SoCal racers crash a ninja 250 completely destroy the front end and part out the stuff I want? The afm' ers must build the things out of ti because they just pick the damn things up and keep going.

O yea that's right Im super cheap...

[alex.s]

can't knock being cheap.