Trailing it Off…

Welcome to the next article in the BST© (BrakeSteerTurn) series

Dem’s da brakes chum

The rear brake on road bikes are a bit mis-understood in my opinion.
The following basic information will hopefully clear up some of the misconceptions and misinformation that has added to the confusion on an already intricate topic. Therefore, this article will try to dispel some of the long-standing advice and narratives that have been published on the subject.

Let me state that I am not saying the front brake is not the better choice most times, or am I denying the fact that the front brake is the most powerful and effective brake to use- when riding in a relatively straight line. But when cornering or on less than dry roads, rear braking when used properly can and will assist in slowing and stabilizing a bicycle as vertical force decreases and lateral force increases… More about that below.

Typically, I’m on and off the rear brake gently and smoothly when cornering because I’m not really using it to stop the bike, but rather to ‘scrub-off’ a slight amount of speed. If I find that I might have carried too much speed into a turn, then this technique will slow the the bike just a bit, to provide more stability rather than utilizing just the front brake when leaned over.

Without getting too technical, eventually the lateral forces or lateral load on the front tire under (front) braking could be exceeded before the load is exceeded on the rear tire. Which is why 9 times out of 10, the front wheel ‘washes’ or slides out before the rear tire does in a crash. (or resulting in a crash)

This holds especially true on anything but dry, debris free pavement and off-camber corners that can be tricky and catch riders out who insist on using the front brake only.

Move to the rear please…

The technique of braking into a corner is often referred to as ‘trailing-off’ or more appropriately, decreasing the initial lever pressure as a rider rolls from corner entry to the apex of a turn. And it is at that point a rider wants to be off the brakes entirely. Sounds easy enough in theory, right? Well sure, almost everything does! Though effective implementation can be slightly complicated or frustrating because it comes down to rider ‘feel’ which is developed and fine-tuned over time. The key to developing a good ‘feel’ is
to simply practice.

Get a grip…

The key contributor to tire grip is the weight or load applied on each tire. The ratio of grip and vertical load is called the co-efficient of friction (AKA- traction) this normally increases/decreases relative to the vertical load (or vertical stiffness) on the tires. And so within these parameters of physics, there are certain aspects which we cannot control- I.E. external forces.

But the factors we do have control over include: tire pressure, tire width and applied braking force. All of which are ‘adjustable’ and can aid in a riders performance and a bikes stability when cornering. As an example, I utilize the rear brake much more than the front, not because I think I will go ‘head over heels’ by using the front brake alone, but because more of my body weight (or CoM) is placed over the rear wheel than the front. (this is true for every rider)

Which means that there is more applied ‘vertical load’ on the rear tire than the front tire, providing more friction or available traction for the bike and rider.

Simply put, traction increases as vertical load on the tire increases, but it is important to know that the relationship between vertical load and traction is not linear. (The laws of physics are not open to interpretation!) Once lateral load exceeds vertical load…traction is then reduced and-or broken.

Please hold, transferring now…

Although a road bicycle has no real suspension to speak of (yet) there is still some slight weight transfer under braking. The more weight that transfers from rear to front, the greater load change on the tires contact patch, which directly relates to the coefficient of friction or available traction. Add in to the mix that a higher center of mass (gravity) will also help to transfer even more weight forward.

(This is why abnormally high seat posts are actually a detriment to performance and handling, though there is virtually no discussion about it) The lower the CoM, the less weight that will be transferred, resulting in a more stable machine.

So with that all said, there is still a definitive line between utilizing rear braking efficiently and locking up the rear wheel and tire. And it is for this reason that most riders then do not utilize the rear brake. That and the at-times myth of the rear wheel coming off the ground on anything but extremely hard braking. (think emergency type stopping)

But, by not using rear braking techniques a rider is forgoing the potential for increased braking power/force and stability WHEN the technique is executed properly. To begin using your rear brake more, start by using both brakes until you can ween yourself off of the front brake as your only choice or the most often used brake.

Slippery when wet…

If this all sounds like nonsense or something you don’t want or think you don’t need to do, then consider that one of the best reasons to start using the rear brake is in wet, rainy or slippery surface conditions. As referenced prior, a bike/rider has more vertical load on the rear tire which will provide more traction (to a point) and so in less than normal dry surface conditions, the potential of losing adhesion on the front tire increases.

Adapting to the given road conditions is critical for safe, efficient riding. If it’s not wet roads, perhaps it will be dirt or gravel roads. This is where a gentle touch on the rear brake helps slow the bike and gives a rider a more control. Better to slightly lock-up the rear, as compared to locking the front tire, which will usually result in a fall/crash.

So my question is; how good a rider would you want to be? How safe, how efficient? Do you want to become more proficient on the road in all conditions? Of course you do, because it’s NOT about going fast. It’s about being in Control, riding safely and having the confidence to do so.

I challenge you sir…or madame

Can you step up your game? I believe you can. I say you have the ability to become better or start using rear braking, trailing-off brake pressure into a corner and executing avoidance maneuvers when and if needed. If you improve these braking/control skills, I guarantee the next time it may start to rain or you encounter an abnormal road surfaces on your ride, you will not only possess the know-how but the confidence to ride without a lot of unnecessary worry and undo hesitation.

By continuing to learn and teach ourselves new techniques, we can improve or lessen the inevitable loss of our skill-set as we age. Think of it as another tool in the toolbox!

The only way to gain confidence is through control. So to this end, we should each practice to attain the necessary feel to learn how to manipulate the rear brake just short of lockup. Not stabbing and grabbing the brakes, but squeezing smoothly AND progressively. Practice today, practice tomorrow, practice on your next ride. But practice!

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6 Responses to Trailing it Off…

  1. Archetype says:

    Reblogged this on The Road to Revelation and commented:

    A recent post I penned on the LeanIn Cornering site…

    Like

  2. bgddyjim says:

    What is meant by an “abnormally high” saddle, specifically? I think I get you but the term is slightly misleading, methinks. First, I have my saddle set at the proper height for my leg length (109% inseam). I bought a smaller frame so that I could set my saddle 4-1/2″ higher than the handlebar (56 as opposed to the recommended 58-59 cm frame).

    If I were to raise my saddle to say, 112% of my inseam, I would experience pain, hip sway, and poor balance and power transfer for a minimal (if even measurable) gain in aerodynamics (thus, obviously, negating any gain).

    Liked by 1 person

    • Archetype says:

      Well, anytime you raise the CoM, you create instability Jim. Of course the amount will vary depending on the height. If you look at vintage machinery, handlebar- saddle delta’s were low. Okay, there was an increase in aero drag, but they are more stable in high speed situations.

      A quick glance at most pro bikes reveals saddle heights extremely high, due to riders riding frames 2-3 sizes too small. Of course a rider can ride any frame size they choose to, just know that there is a point when it becomes detrimental. Not optimal. The high-er CoM rears its ugly head in high speed corners and descents.

      There is a reason race cars and superbikes attempt to place all the mechanicals as low as possible, including the driver and rider. But this proven principle seems lost on road bikes.

      Hell, many mtb’s utilize droppers for this very reason, to lower a riders CoM on downhills, for rider stability.

      Liked by 1 person

      • bgddyjim says:

        Oh, there’s no doubt you’re right. The point I was trying to get at was there are offsetting forces at work here. First, with the saddle high and a smaller frame, the butt may be up but the upper body is lower. This more “aero” posture translates directly into watts on the majority of a race. In other words, it’s worth giving a little descending speed for a greater gain over 90% of the ride.

        No chance I’d trade my setup for a larger frame and a more upright posture, no matter how well the bike descended or cornered. It’s too comfortable… and fast.

        Had to throw “fast” in there.

        Liked by 1 person

      • Archetype says:

        Oh for sure, I agree it definitely depends on the type and style of riding one does. In your case, it is more beneficial to be aero. My comments are geared more towards many of the pro’s. Some of their bike setups are ridiculous from a engineering standpoint.

        They install these extremely long stems, ride too small a frame and have way too high a seat post. All of which ‘counters’ what the factory engineers manufacture.

        Again, making these bikes unstable. But it is never spoken about or addressed. The focus is so much on aero that many riders and teams forgo the crucial aspect of stability.

        The number one priority of GP and SBK teams/mechanics is tire contact patch and all of the generating forces at work- and how best to overcome them, without upsetting the dynamics of the designed chassis or frame.

        Something that is seemingly lost on road bikes. Where tires and the center of mass play huge roles in bike stability.

        And this would primarily be in descending. Now most of us do not have access to 3, 5, or 10 mile descents. But they are commonplace in Europe and other parts of the world where races are held.

        Like

    • Archetype says:

      Abnormally is a bit vague I suppose. The abnormal distance will depend on rider height/inseam measurements. But suffice to say, the very high CoM of some bikes is no doubt a contributing factor in downhill descent crashes. But it is rarely if ever talked about it. When a GP-Superbike or race car crashes, teams and riders/drivers POUR over the data and situation. Wanting to know exactly the contributing causes.

      Analyses to the hilt… but not so much on bicycles. It is usually shrugged off as just a crash, typically blaming someone or something else- RATHER than pointing to the real cause. Which is a rider losing control, which 99.99% of the time, is the case. Why did the rider lose control? Many factors involved in each specific incident, but never any real analyses. .

      For as sophisticated as road cycling can be, there is a lot that is archaic and limited with regard to the applied physics and how they affect crashes and performances. Other than aerodynamics, not much is discussed or intricately analyzed.

      Liked by 1 person

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