Almost The Last Braking Discussion Thread You Will Ever Need

[RhythmRider]

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In another thread, a tangent discussion of proper braking technique arose. The topic comes up from time to time and people have varying opinions about it. This thread exists to continue the discussion.

Have at it!

tzrider

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Every bike is different, and it takes experimentation to find the limit of braking on any given bike, but the technique for doing that remains the same. Squeeze progressively on the front without locking the wheel, use the rear brake as best as you can without locking the rear wheel. Some bikes have their weight placed further back, so the rear brake would be a little more effective on those bikes, but the front is always going to be the most powerful due to the forward weight transfer.

 

[p14]

OK, let's take your SV--for sure you can lift the rear on that, no? Or does it slide first?

 

[RhythmRider]

What do you think?

 

[p14]

What do you think?

Gotta believe with good tires and decent pavement, it would lift the rear. We have a 650 Ninja that does it pretty easy.

 

[RhythmRider]

Yeah, on sport standards like the SV, the tendency would be to lift the rear if you're maximizing use of the front brake. On a fully dressed cruiser, you probably wouldn't be able to do it, and that would allow more braking from the rear wheel since it would still be in contact with the ground.

 

[stangmx13]

p14, wats your pt?? ive seen stoppies on just about every type of motorcycle... and this has absolutely nothing to do w/ maximizing stopping power. in fact, simply showing that lifting the rear tire is possible has no relevance w/ the fundamentals of controlling a motorcycle, any motorcycle.

 

[tzrider]

p14, wats your pt?? ive seen stoppies on just about every type of motorcycle... and this has absolutely nothing to do w/ maximizing stopping power.

P14 can answer for himself, but here's my take: Some motorcycles will slide the front tire before they will stoppie, regardless of pavement and tire condition. For these bikes, you cannot reach 100% of the stopping potential without using the rear brake.

On bikes that will stoppie before they will skid the front, there is no point in being on the rear brake under 100% braking and some definite downsides to being on the rear brake in that situation.

 

[p14]

P14 can answer for himself, but here's my take: Some motorcycles will slide the front tire before they will stoppie, regardless of pavement and tire condition. For these bikes, you cannot reach 100% of the stopping potential without using the rear brake.

On bikes that will stoppie before they will skid the front, there is no point in being on the rear brake under 100% braking and some definite downsides to being on the rear brake in that situation.

Thanks TZ, we are on the same page. Stangmx: I've seen guys lock the rear and hit things. I watced a pro stuntman do it on a set one day, while rehearsing! If a bike is capable of all the braking done with the front, why train with the rear? In a panic, won't the rider default to the trained mode? If the rear is locked up, the bike can't be steered (and how hard is it to lock the rear, if the front is doing 80-90%+).

 

[Burning1]

P14 can answer for himself, but here's my take: Some motorcycles will slide the front tire before they will stoppie, regardless of pavement and tire condition. For these bikes, you cannot reach 100% of the stopping potential without using the rear brake.

I would go as far as to say that *all* bikes can slide the front before they will stoppie. Traction conditions are often imperfect, and proper use of the rear brake is critical for maximizing safety.

On a good dry track, using only the front may be a reasonable strategy -- freeing up a rider's over-taxed attention, and allowing more focus on other tasks. However, on a wet road, using the rear brake is critically important for getting a feel for available traction and minimizing stopping distances, even with a modern sport bike.

While I agree that a locked rear tire can be dangerous, I would argue that a locked front tire is significantly more so. Certainly, most of us have over-braked with the rear on occasion, and recognize that it's manageable, and reasonably easy to recover from. With that in mind, in bad traction conditions, I personally prefer to slightly over-apply the rear. By testing the edges of traction using the rear brake, I can get a good feel for how much traction is available at the front.

Of course, it *should* go without saying that In the rain, when traction is drastically reduced, the rear tire plays a very large part in delivering maximal overall braking power.

Even in the dry, the rear brake has a strong impact on motorcycle stability under braking, and can using the rear brake exclusively for the last 3-5MPH of deceleration can help a rider maintain balance coming into a stop. I've also found that firm application of the rear brake during the initial moments of braking (when the front suspension hasn't fully settled) can have a major impact on stopping distances, often reducing them by as much as 20 feet when slowing from freeway speeds.

In my opinion, there are large benefits in learning how to use the rear brake effectively. Sure, it's often mis-used and can be dangerous when abused... But that's all the more reason to learn to use it correctly. When applied in the right situation, the rear brake is a valuable tool.

 

[tzrider]

Even in the dry, the rear brake has a strong impact on motorcycle stability under braking, and can using the rear brake exclusively for the last 3-5MPH of deceleration can help a rider maintain balance coming into a stop. I've also found that firm application of the rear brake during the initial moments of braking (when the front suspension hasn't fully settled) can have a major impact on stopping distances, often reducing them by as much as 20 feet when slowing from freeway speeds.

If you're talking about a sportbike, the fact you are able to get anything out of the rear brake indicates you're not getting as much as you could out of the front. At the true threshold, there's essentially no weight on the rear.

The time that stopping distances matter most is in emergencies. In a sudden emergency, you don't monkey around applying the rear brake first. It's a waste of time you don't have. You might be able to get away with applying both brakes simultaneously, though the probability of locking the rear is very high under those conditions. When riders lock the rear unexpectedly they tend to let go of both brakes.

 

[JeffKoch]

I would go as far as to say that *all* bikes can slide the front before they will stoppie.

In my experience on sportbikes, this isn't correct, at least on reasonably clean dry pavement. Cruisers, fine, but not sportbikes. Some will argue that applying a bit of rear brake early on will help settle the supension and allow you to brake harder using the front, but in my experience this isn't worth the effort - you can stop astonishingly quickly using the front brake alone.

 

[Burning1]

If you're talking about a sportbike, the fact you are able to get anything out of the rear brake indicates you're not getting as much as you could out of the front. At the true threshold, there's essentially no weight on the rear.

The time that stopping distances matter most is in emergencies. In a sudden emergency, you don't monkey around applying the rear brake first. It's a waste of time you don't have. You might be able to get away with applying both brakes simultaneously, though the probability of locking the rear is very high under those conditions. When riders lock the rear unexpectedly they tend to let go of both brakes.

I tend to lift the rear under hard braking on clean dry pavement, so I would suspect that I am in fact quite capable of using the front brake effectively.

I never suggested that the rear brake should be applied first -- both brakes should be applied at the same time. This technique is beneficial because a rider has to ease on the front brake during initial moments of braking in order to settle the front suspension -- if he or she tries to apply maximal braking before the tire and suspension settle, the front wheel will lock and the rider will go down.

This is *not* true of the rear brake. Full pressure can be applied at the rear brake almost immediately. As the rider increases pressure on the front brake, he or she must reduce pressure on the rear brake in order to prevent a rear wheel lockup.

I must emphasize that this technique does *not* change the way the rider uses the front brake, and that it's actually pretty easy to commit to muscle memory. In my experience, the technique is easier to learn than matching engine speed while down shifting. When applied correctly, it does improve stopping distances to a noticeable degree.

In my experience on sportbikes, this isn't correct, at least on reasonably clean dry pavement.

That's exactly my point. If all you do is ride on clean, dry pavement, you should be fine using only the front brake.

But we may find ourselves riding in the rain, or braking in a patch of sand, or braking across a painted line, etc. etc. etc. There are many adverse situations out there, and failing to train for them may leave us at a disadvantage when we encounter some of the most demanding braking situations imaginable.

 

[tzrider]

This technique is beneficial because a rider has to ease on the front brake during initial moments of braking in order to settle the front suspension -- if he or she tries to apply maximal braking before the tire and suspension settle, the front wheel will lock and the rider will go down.

How long does it take to fully transfer weight to the front?

 

[Burning1]

How long does it take to fully transfer weight to the front?

I usually load the front by feel, so it's very hard to give an exact answer. I figure it takes about half a second to settle the suspension, but that figure varies based on the suspension stiffness and braking force applied.

Here's the thing: In half a second, a motorcycle traveling at 60 miles per hour covers about 44 feet of roadway. If I can brake 25% more effectively over that 44 feet, I've reduced my stopping distance by 11 feet. That can mean the difference between an accident and avoidance, it can reduce the speed at which an accident occurs, or it can be used to out brake another rider on the track.

(I realize that my calculations are grossly simplified, and don't reflect inertia or deceleration curves.)

In my opinion, the trade off is pretty minimal. Developing the skill improved my confidence with the rear brake, and reduces my stopping distance. I can practice it during my normal street riding, in situations that are not taxing my riding ability at all. Once I committed the skill to muscle memory, I found that it consumes trivial amounts of valuable corner entrance attention, and does so when that attention is minimally taxed, and helps to improve my feel for braking traction.

Best of all, the skill actually emphasizes *getting off the rear brake* as front braking forces increase. For many new riders, this is a critical skill that would go a long way towards preventing rear wheel lockups.

For me, it was a no-brainier to learn.

BTW: This is not a technique I've read about in any book.

 

[ucb]

So where exactly are you getting this "hard data" from?

As for this "ease on the front brake" theory of yours. You do realize that using the rear brake while you "ease on the front" is preventing all the weight from transferring to the front quickly, thus increasing the time to load the front, DECREASING the effectiveness of the front brake and the TIME spent on the front brake, which provides 10 fold more stopping power than the rear. Im not going to make up numbers like you, but intuitively it doesn't make much sense to me at all. You are sacrificing your MOST effective stopping tool, to use your LEAST effective stopping tool. In addition to that, it sounds as if you are condoning full rear brake pressure, that sounds like a quick way to lock up the rear and dump it. Not only that, but as long as you are SMOOTH in your brake application, you can loft the rear fine and dandy almost instantly, without a hint of front tire slide. I've lofted the rear plenty, but haven't slide the front a single time under hard braking. I don't think you are giving the front tire enough credit in terms of the shear grip is really is capable of.

And I can hardly believe using the rear and front simultaneously results in 25% more effective braking, if that was truly the case, you WOULD be able to read it out of a book.

 

[RhythmRider]

You do realize that using the rear brake while you "ease on the front" is preventing all the weight from transferring to the front quickly

Maybe I'm not reading this correctly... are you saying that using the rear brake slows down forward weight transfer?

'cause if you are...

 

[stangmx13]

Maybe I'm not reading this correctly... are you saying that using the rear brake slows down forward weight transfer?

'cause if you are...

haha, it does actually.

this is exactly y i asked (in a post on the prev page).... P14 (and Tz), i completely disagree w/ both of u about stoppies and stopping distances. rear suspension dynamics affects things drastically when applying the rear brake... ie weight transfer forwards is affected by application of the rear brake. by applying the rear brake, the swingarm extends backwards causing the bike to squat. this squat lessens weight transfer to the front tire, increasing the amount of braking force the rear tire can sustain before locking. so in a situation w/ proper rear brake application, the rider is still applying all the load the front tire can handle but has now added extra braking force at the rear tire.

jus as some more anecdotal evidence... ive locked both tires on a sportbike in a panic stop. the rear locked first, then the front, and the rear tire stayed on the ground (evident by the spacing and length of the skid marks). through your reasoning, the rear tire should have atleast skipped off the ground before the front tire locked because the bike was well capable of stoppies and the braking force should have overcome the weight keeping the rear tire on the ground b4 the front overloaded. the bike didnt make it through that one and of course, i would have stopped sooner had i not locked everything... but the skid marks were short so it didnt matter anyway.

 

[tzrider]

rear suspension dynamics affects things drastically when applying the rear brake... ie weight transfer forwards is affected by application of the rear brake. by applying the rear brake, the swingarm extends backwards causing the bike to squat. this squat lessens weight transfer to the front tire, increasing the amount of braking force the rear tire can sustain before locking.

To say it differently, the squat lowers the CG of the bike and changes the ratio of the length of the wheelbase to the height of the CG. There is a tiny bit less weight transfer for a given rate of deceleration, up to the point where 100% is on the front. But you can get 100% of the weight on the front either way.

You guys are right that there is a theoretical gain in this, from a purely mechanical perspective. It's quite small, however, and I think you're underestimating the difficulties in getting a human to threshold brake either wheel while trying to do something else at the same time. This isn't trivial. In a true emergency, riders who use both brakes often lock the rear. When they do, they 1) cannot steer and 2) tend to let go of both brakes, at least momentarily.

 

[Burning1]

As for this "ease on the front brake" theory of yours. You do realize that using the rear brake while you "ease on the front" is preventing all the weight from transferring to the front quickly, thus increasing the time to load the front, DECREASING the effectiveness of the front brake and the TIME spent on the front brake, which provides 10 fold more stopping power than the rear. Im not going to make up numbers like you, but intuitively it doesn't make much sense to me at all. You are sacrificing your MOST effective stopping tool, to use your LEAST effective stopping tool.

UCB: You've given me some great debates, but you're way off base on this one. Seriously.

Weight transfer to the front tire has absolutely nothing to do with which brake is applied, and everything to do with the center of gravity of the bike and the moment of force produced by braking. Applying the rear brake causes weight to transfer to the front -- this is exactly *why* the rear brake is so ineffective: it's self defeating.

Here's a thought experiment -- imagine a bike with a center of gravity positioned 3 feet below the ground. How would this affect handling?

In addition to that, it sounds as if you are condoning full rear brake pressure, that sounds like a quick way to lock up the rear and dump it. Not only that, but as long as you are SMOOTH in your brake application, you can loft the rear fine and dandy almost instantly, without a hint of front tire slide. I've lofted the rear plenty, but haven't slide the front a single time under hard braking. I don't think you are giving the front tire enough credit in terms of the shear grip is really is capable of.

And I can hardly believe using the rear and front simultaneously results in 25% more effective braking, if that was truly the case, you WOULD be able to read it out of a book.

Define full brake pressure. Do you mean pressing the brake as hard as possible? Do you mean locking the brake up? Or do I mean applying as much brake pressure as possible without locking or lifting a wheel? Yes, my statement could have used some clarification... But did you really have to automatically assume that I made the stupidest statement imaginable?

In your post you mention smooth braking. That's exactly the kind of braking force I suggest, just a different word for it. Hint: it's possible to be fast and smooth, but it's impossible to be smooth and instantaneous -- mutually exclusive terms.

Finally, at no point did I suggest that this technique would lead to 25% better braking. That would imply 25% more deceleration for the duration of braking. I'm suggesting that it's possible to improve the approach to initial brake application, leading to a slight, but noticeable reduction in stopping distance.

Re-read my post.

 

[Burning1]

TZRider: Squatting the bike has an advantage in that it increases the total amount of braking force that can be applied before the rear wheel lifts. But that's not the point of the technique I describe. What I'm suggesting is that using the rear brake properly increases the amount of braking force that produced in the first moments of brake application.

The numbers I suggest aren't huge, but they are potentially beneficial, and they do reflect my real world experience.