• There has been a recent cluster of spammers accessing BARFer accounts and posting spam. To safeguard your account, please consider changing your password. It would be even better to take the additional step of enabling 2 Factor Authentication (2FA) on your BARF account. Read more here.

Trail Braking Basics

My understanding of trail braking is using your front brake to slow up to the point of rolling on the throttle so that more traction is on the front tire for the turn-in. Seems like the focus is on the front tire, not the back.

This is something I have been working on since I started out riding on large twins and developed the habit of engine braking into turns instead of using the real brakes. As I get faster I try to focus on a good braking to throttle transition and holding the brakes later into the turn until my speed is set (along with a later apex).

Your videos are always a nice production, but this one seems more about general cornering.
 
It's about loads and demands. It's easy to focus on just one thing (like planting the front) and forgetting that you can read the front by watching the rear. It's about balancing and not unsettling the bike. Smooth is vital because the transition from brake to gas is when your limited quantity (traction) is being shared and shifted between sources and demands.
 
Last edited:
There's a lot of misunderstanding here and different meanings for the word. "Trail" braking on the track refers to using the front brake to change the trail of the bike. Basically when you enter most corners you're hard on the brakes and the front end is compressed almost fully. Trail braking involves backing out of the brakes as you turn in, but maintaining a SMALL amount of brake all the way to the point of max lean. This has several effects. It allows you to continue braking further than you could if you only brake upright. It puts more pressure on the front end and ensures a bit more traction ( which can be overdone). Mostly it keeps the front end compressed and allows the bike to turn easier. The braking ends at the point of max lean and that's when you start to shift to throttle, which is determined by lean angle. Reduce lean angle slightly, add a tiny bit of throttle.
 
^^^Once again Ernie gives a great explanation. I always thought it referred to "trailing off" the brakes -- now I know better!
 
afm199 said:
The braking ends at the point of max lean and that's when you start to shift to throttle, which is determined by lean angle. Reduce lean angle slightly, add a tiny bit of throttle.
Click to expand...

I just recently tried this on my last trackday. My mind is now blown. But I have a follow up question....

From the point where you release the brake, are you coasting for a bit before applying the throttle? Or does one release the brake and at almost the same time applying a little bit of throttle.

I'm trying to get the steps/sequence down. I would like to practice more and refine my technique.
 
danate said:
My understanding of trail braking is using your front brake to slow up to the point of rolling on the throttle so that more traction is on the front tire for the turn-in. Seems like the focus is on the front tire, not the back.
Click to expand...

Trail braking generally reduces available traction at the front tire. This is basic Coefficient of Friction (CoF.) Loading a tire increases traction demands linearly with available traction; more weight consumes available traction exactly as fast as it adds traction. But with braking and accelerating, the act of braking or accelerating places additional strain on the tire, so available traction tends to be reduced.

It can however benefit entry speed, entry line, and it can help control the front suspension.
 
Last edited:
Two things I took away from listening to Ken Hill:

How to apply (gradually build pressure in) the brakes and equally (more?) important, how to gradually release pressure on the brakes to prevent the suspension geometry and tires' contact patches from changing too quickly.

And: Use your brakes until your happy with your speed and direction.

So simple.
fastersafer.com
:thumbup
 
airrix said:
I just recently tried this on my last trackday. My mind is now blown. But I have a follow up question....

From the point where you release the brake, are you coasting for a bit before applying the throttle? Or does one release the brake and at almost the same time applying a little bit of throttle.

I'm trying to get the steps/sequence down. I would like to practice more and refine my technique.
Click to expand...

Depends on the corner, ideally you are on the brakes or the gas. A few pros will be on both at the same time. don't try this

Burning1 said:
Trail braking generally reduces available traction at the front tire. This is basic Coefficient of Friction (CoF.) Loading a tire increases traction demands linearly with available traction; more weight consumes available traction exactly as fast as it adds traction. But with braking and accelerating, the act of braking or accelerating places additional strain on the tire, so available traction tends to be reduced.

It can however benefit entry speed, entry line, and it can help control the front suspension.
Click to expand...

Bingo you have 10 traction units. If you trail brake in the corner you'll use more of them. And have fewer left. However both initial braking and accelleration need gradual input to give the tire a chance to load up and squish a bit.
 
Last edited:
afm199 said:
There's a lot of misunderstanding here and different meanings for the word. "Trail" braking on the track refers to using the front brake to change the trail of the bike.
Click to expand...

MCCRASH said:
^^^Once again Ernie gives a great explanation. I always thought it referred to "trailing off" the brakes -- now I know better!
Click to expand...

Question: If the 'trail' in trail-braking refers to the chassis geometry of the motorcycle, what does the term mean when used in/for automobiles? Why is it different?

Answer: It isn't different. 'Trail' refers to the trailing off of / reduction in brake pressure as the vehicle enters the turn. The term has the same definition regardless of vehicle, moto or auto.
 
Enchanter said:
Question: If the 'trail' in trail-braking refers to the chassis geometry of the motorcycle, what does the term mean when used in/for automobiles? Why is it different?

Answer: It isn't different. 'Trail' refers to the trailing off of / reduction in brake pressure as the vehicle enters the turn. The term has the same definition regardless of vehicle, moto or auto.
Click to expand...

No, you have the same definition. We can argue about the term at length, but the point I am making is that there is a need to understand how changing the trail of a moto by braking slightly makes it much easier to turn and place where you want it.


That's why I said there is confusion. Trail braking to slow the vehicle and trail braking to change trail are two different animals. On a bike I will "trail" the rear brake to scrub off some speed as well as the front, and the rear brake is trailed for one reason, to help slow down. The front brake is used to get the bike to turn, again this is after you have done most of your upright braking.

On a four wheel vehicle trail braking is trailing off to the apex, and as it is on a two wheel. However the goal is different. On a two wheel vehicle the primary purpose is not to get the last bit of braking all the way to the apex, that's a secondary. It is to compress the front of the bike and make the turn in easier and more effective. It's so much easier to turn a bike on the brakes, and that's why it's done. The bit of braking done in a corner like T8 at Thill isn't done to slow the bike down, it's done to help steer it.

In this case I think we're discussing semantics.
 
Last edited:
More lean = less brake.

When you are fully off the brake you feed in more throttle.

Less lean = more throttle.

"Coasting" through a corner definitely feels unstable, at least for me, so partial braking blends into partial throttle as I transition the apex.
 
afm199 said:
No, you have the same definition. We can argue about the term at length, but the point I am making is that there is a need to understand how changing the trail of a moto by braking slightly makes it much easier to turn and place where you want it.


That's why I said there is confusion. Trail braking to slow the vehicle and trail braking to change trail are two different animals. On a bike I will "trail" the rear brake to scrub off some speed as well as the front, and the rear brake is trailed for one reason, to help slow down. The front brake is used to get the bike to turn, again this is after you have done most of your upright braking.

On a four wheel vehicle trail braking is trailing off to the apex, and as it is on a two wheel. However the goal is different. On a two wheel vehicle the primary purpose is not to get the last bit of braking all the way to the apex, that's a secondary. It is to compress the front of the bike and make the turn in easier and more effective. It's so much easier to turn a bike on the brakes, and that's why it's done. The bit of braking done in a corner like T8 at Thill isn't done to slow the bike down, it's done to help steer it.

In this case I think we're discussing semantics.
Click to expand...

The technique is named for how it is performed. What it does to the steering geometry is important to understand, but the common term 'trail' is merely coincidental.
 
Enchanter said:
The technique is named for how it is performed. What it does to the steering geometry is important to understand, but the common term 'trail' is merely coincidental.
Click to expand...

If you insist, I allow you your opinion. :p
 
afm199 said:
We can argue about the term at length, but the point I am making is that there is a need to understand how changing the trail of a moto by braking slightly makes it much easier to turn and place where you want it.
Click to expand...

I have yet to ride a bike that turns more easily with the brakes applied than off the brakes. The trail doesn't generally get shorter, for while the rake gets steeper, the contact patch also distorts to the rear, usually more than offsetting any trail reduction you would get from steeper rake.

Braking can make it easier for some riders to place the bike in the turn, but it isn't because of the trail change, it's because the bike continues to slow, which tightens the arc at any given lean angle.
 
tzrider said:
Braking can make it easier for some riders to place the bike in the turn, but it isn't because of the trail change, it's because the bike continues to slow, which tightens the arc at any given lean angle.
Click to expand...

I spent a couple sessions working on braking last month at Laguna, focusing on a few turns in particular. In the same turn, at higher speeds, I found it easier to turn in when trail braking than at lower speeds when there was a gap between braking and turning, and my front end had rebounded. Note that I say *trail* braking -- on the brakes harder than that, the bike definitely does not want to turn.
 
The semantics of this are what the average rider finds confounding. In racing there's the big issue of geometry and increasing speed. In average user circles (as well as training) the concept is much cleaner: If you're braking into the turn: that's trail braking.

Most folks naturally want to brake into the turn. It's what we do in our cars. As far as riders, go observe an MSF or other training session and you'll see that dang brake light on all the way to the apex and then hear the throttle open as the rider exits the curve. Why? Because that's how most folks drive their cars. Not to go faster but because they're afraid and naturally want to slow in the curve until they're sure they're OK. Just watch some time.

So what can you call it when a rider is on the brakes into the turn--what moniker can you give it? Traditionally, braking to the apex has been called "Trail Braking". Racers do it to increase corner speed. (Brake until you see Jesus, then gas it out). Over the years Trail Braking has come to mean carrying the brakes into the turn. It's clean, it's clear, it's simple and that's how most training curriculum address the issue.

Because the term's genesis was in racing there's a "dark arts" feel about it. Folks want it to be a crazy, cool secret go fast technique. Unfortunately in training we spend a lot of time trying to get newbs NOT to trail brake so they can get their technique for wise entry speed and line selection sorted before they start playing with when the transition from brakes to throttle works into that equation.
 
MCCRASH said:
I spent a couple sessions working on braking last month at Laguna, focusing on a few turns in particular. In the same turn, at higher speeds, I found it easier to turn in when trail braking than at lower speeds when there was a gap between braking and turning, and my front end had rebounded. Note that I say *trail* braking -- on the brakes harder than that, the bike definitely does not want to turn.
Click to expand...

If you can say, what specifically was easier? This is always a source of mystery for me in these conversations because I get the sense that people may focus on different things when they speak of ease of turn-in.

In my own case, I think of ease of turn-in as being the amount of force on the bars it takes to set the lean angle of the bike and get it on the line I want. Using that measure, I have never found any amount of braking to make this easier; it always adds to the bar effort.

A simple test I employed was to approach a corner on the brakes at a speed where the exact location of my turn-in wasn't critical. While on the brakes, I would apply light pressure straight forward on the inside bar. With the front brake applied and pressure on the bar, I would then progressively release the brakes while maintaining the same bar pressure. The bike always tips in more dramatically as the brakes come off.

Am I measuring something different than you are?
 
You must log in or register to reply here.
Back
Top