How does braking affect your corner speed?

At the recent 2018 mountain bike world championships in Lenzerheide, Switzerland, Claudio Calouri and Rob Warner were talking a lot about braking.

Riders who appeared to do too much braking went visually more slowly than riders with a “good” braking strategy. And of course, this was apparent in race times.

More often than not the riders who consistently appeared to brake well went much more quickly over the entire race run.

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Yes, we all know that braking can affect how fast you are going, but so far not many people know what a good braking pattern looks like.

The data is still very new, but I wrote about the very first braking study during XC racing here. It turned out that you can change your braking from lap-to-lap and make up for fatiguing legs!

That was over a whole XC lap… But how much does braking matter heading in to one single turn?

I was really curious about this, so using the most accurate brake power meter, I tested several riders’ braking strategies over a short descent into a left hand turn.

This article was recently reviewed and published in the International Journal of Performance Analysis in Sport.

**Check out this link to a free e-print!**

 

Why do riders brake heading in to turns?

Riders brake when they feel that they are going too quickly. For different riders this will happen at different speeds. Pro riders are much more willing to travel very very quickly, while beginners will begin slowing down even when they are not moving very fast–especially when heading in to turns.

There are a few reasons for this.

And it’s a bit of a vicious cycle!

The first reason is that the pros are much more confident. And this goes beyond just being more willing to send it!

master-attack-position

The pros are very confident in their bikes–and especially in their ability to slow down in a split second if they need to!

Another main reason is that the pros are willing to ride faster is that they have the bike handling skills to be able to take the turn at a very high speed. They simply can go faster  in the turn, thanks to good weight distribution on the bike, proper lean angles and control of the direction of the bike.

But by slowing down too much before a turn and not having the skill to exit with speed means you are not riding very fast or very in control.

 

What did we test and what were the results?

Of the dozens of riders we tested, we found some really good results.

Corner plot

We had riders coast down a short, straight hill (no chain) to control their speed on the same bike with a brake power meter. Sections A and B were in a straight line, but sections C and D were the two parts of the turn, split at the apex. We controlled the line they took as much as possible by taping the track narrowly. They did this 3 times in a row.

Once we collected all the data we broke the short track into sections on the computer and analysed their pattern of braking and where they were doing their braking. The measurements we focus on were,

  • Brake work: the total energy removed through braking
  • Brake time: the total time spent braking
  • Brake power: the energy done in braking divided by the time spent braking (i.e. how hard they were braking)
  • Time: the time to complete the whole track and time to complete each section

 

MTB Corner Braking Analysis with Brake Power Meter

Overall, the less experienced riders started braking very soon, and really most of them ended up braking most of the way through the turn.

But the experienced riders were either off of the brakes or on the brakes. The fast rider was braking very hard, but then was totally off of the brakes, whereas the slower rider was lightly riding the brake before and through the turn.

If you look at the graph you can really see how this affected their speed (velocity).

It’s really interesting to note that the relative energy (work) taken away by braking between the two riders was not overly different, but brake power was much higher for the experienced rider. This is why high brake power is good–all braking efforts are concentrated to a really short time.

Also note that the inexperienced rider tapped the brakes pretty lightly near the apex of the corner, and since he was already going slow, his speed really dropped again.

 

What does this mean for us?

By braking hard and concentrating braking to a very small section of the track, we are able to do two things:

  1. Braking late allows us to spend more time before the turn riding at a fast pace, whereas when we brake early we spend more total time going slow
  2. Letting off the brakes while we are in the turn allows us to maintain traction, carry speed through the turn and exit the turn with speed

In the graph above simply using a good braking strategy was good for almost 2 seconds in one corner!

And how many corners are there on a mountain bike track?

A lot!

 

What can you do to brake better?

It may be true that you don’t have the confidence or the bike control of a pro. But that doesn’t mean you are stuck riding slow!

Try this training session to ride faster around corners:

  • Find a trail with a turn that you can coast in to and easily repeat
  • Pick a landmark as your start and coast down into and through the turn.
  • How was your braking?
  • Now repeat the turn, but this time wait as long as possible to start braking before you start turning.
  • How was your speed?
  • This time, wait as long as possible to start braking, but also pay attention to letting off the brakes through the turn.
  • How was your speed?

Remember, it’s OK to brake really hard before the turns! But if you are braking and turning at the same time you will eventually lose control, especially during hard braking.

Just think: if you can save even a split second in every turn, you can go much faster!

I’m really excited that one day soon riders will be able to link up their brake power meters to their POV cameras for some really good feedback of what they are really doing out there.

Keep an eye out for the next article where we will talk about front and rear brake usage!

 

You might like these articles:

How important is braking in mountain biking?

World’s first MTB braking research is published in scientific journal (plus 50 free copies)

2018 USAC MTB National Championships Report

New Training Plans Added!

5 Ways to Use the Brake Power Meter to Train Yourself to Ride Faster

5 Science Hacks to Help You Race Mountain Bikes Faster

Why do you have to be fit for gravity racing?

How to avoid blowing up in MTB racing

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