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Old 05-04-2013, 07:48 AM   #31
sloperut
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Originally Posted by shaddix View Post
That really depends on the corner doesn't it? Flick vs trailbraking

I find it very difficult to find a corner I can take safely that allows me to carry enough speed to trailbrake effectively(street)
It does. However, I prefer to have more than one option at hand for any given circumstance. I'd rather not limit myself to one way, for instance, only setting up speed prior to turn in.

Why is trail braking only connected with faster cornering speeds? Does it have a use a slower speeds?

Good discussion here
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Old 05-04-2013, 08:17 AM   #32
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Originally Posted by sloperut View Post
Why is trail braking only connected with faster cornering speeds? Does it have a use a slower speeds?
It doesn't have a use at slower speeds, because it's a high-speed cornering maneuver. Here is the classic trail-braking scenario. You are coming up to a corner. You are braking as hard as you can. You waited so long to brake that you are still too fast for the corner at your tip-in point. In a very delicate and carefully timed maneuver you progressively ease off the brakes as you increase your lean angle, going right up to the edge of available traction. It's tricky, it's dangerous, and it frequently leads to crashes. I have a hard time believing my fellow paunchy, middle-aged faux adventurers are riding to that level on the street.

I can easily believe that they are meandering about, giving the front brake lever a gentle squeeze every now and then with no real thought or purpose in mind. Then coming home and discussing trail-braking on the internet.
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Old 05-04-2013, 08:46 AM   #33
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Originally Posted by Jim Moore View Post
I can easily believe that they are meandering about, giving the front brake lever a gentle squeeze every now and then with no real thought or purpose in mind. Then coming home and discussing trail-braking on the internet.

Witch! Burn him!

Some of these folks have been riding for months and in that short time they've been at the very limits of traction!
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Old 05-04-2013, 09:09 AM   #34
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Originally Posted by sloperut View Post
I was reading something, I believe by Keith Code, where he hinted that trail braking was the less expert technique vs. braking upright prior to the turn. I thought about it and it kind of makes sense: If you do all your braking while upright, prior to leaning into a turn, your have to exactly, expertly, gauge your entry speed and basically throw away opportunities to adjust your speed. Kind of a gamble if the road throws something your way like gravel, a corner that decreases quicker that you thought is would, etc.

Maybe he was just being thought provoking but it did make me think about trail braking vs. getting all my braking done before the turn.

Oh, and btw, I trail brake while street riding.
Superbike school doesn't say whether you should or shouldn't trail brake. The lessons they teach sort of let you decide for yourself. Which pretty much sums up to trail braking is a good tool to use for certain corners but can be a much slower way to get around the track if used incorrectly. Also... it can be a good way to low side.

I do remember hearing one coach say technically you should trail brake into every corner. You should always be releasing the brake in a smooth controlled way (trail braking) to set your entry speed to the exact point you want. If you just suddenly release the brake you don't really have an accurate idea of how much speed you scrubbed off.

Usually the fastest way to get around a track or set of twisties is to be on the throttle for as long as possible while maintaining max apex speed. For most people trail braking makes them reach a slower apex speed and get on the throttle later. And as it was said earlier, it depends on the corner.
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Old 05-04-2013, 09:15 AM   #35
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I started using the front brake in really steep pavement switchbacks with great success. Before I would not use the brakes at all going in and pick up too much speed going thru the corner. (going downhill)

A little front brake going in gradually letting off towards exit keeps speeds in check and feels more planted.

If you have spent in anytime in the rockies you know the kind of pavement switchbacks I'm talking about.


I also just saw this thread, I had no idea this was called "trail braking" I was just happened to figure this out.
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Old 05-04-2013, 11:06 AM   #36
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Originally Posted by Pointyhead View Post
Come and ride in the mountains of Italy. Terribly steep and littered with switchback and decreasing radius turns. You too will understand trail braking.
I couldn't agree more. Even at sensible, street, speeds trail braking is very useful on a twisty mountain decent.
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Old 05-04-2013, 01:06 PM   #37
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Originally Posted by sloperut View Post
I couldn't agree more. Even at sensible, street, speeds trail braking is very useful on a twisty mountain decent.
Using the front brake through a turn weights the front tire, increasing traction on the front tire, as well as loading the front suspension so that when the suspension loads up due to the turn (increasing turn especially) you can remove some front suspension load by letting off the front brake. This way the bike goes around the corner with a stable suspension and all the (max) traction used up between braking and turning all the way through the turn.

Where you are putting your weight on the bike is real important too. Not so much front to back on the pavement and on a pavement type bike but much more so on dirt bike in the dirt.

Braking and accelerating in a corner on the street are more about making the bike turn then slowing down and speeding up.

If you are slowing down for corners (on a bike) on the street you are probably almost doubling the posted speed limit. You might use these techniques to be fast on sharp corners, even intersections. Not a good idea for all kinds of reasons.

Unlike a car a bike cannot go too fast or too slow around a corner. There is only one speed the bike can around a given corner at a certain lean angle.

The maximum speed the bike will go around a corner is at it's maximum lean angle (the tire traction may run out before the physical limits of lean are achieved). You could think of every corner has having a maximum speed for your bikes max lean angle - instead of thinking of a sharp curve and a less sharp curve you could think of a corner as 143 mph corner and a 123 mph corner. Keep in mind the max lean angle is measured to the center of the earth which takes care of road tilt and off camber situations.

So you are going to do the 143 mph corner, and you are going 143 mph, no braking or accelerating required. Just lean the bike to the max lean angle and go around the corner. If you are going faster than 143 mph you need to slow down to 143 mph, achieve max lean and when the roads straightens out, increase speed again past 143 mph. Using the brakes and accelerating moves the weight from the front and back of bike and makes the whole turning thing way more complicated then just the max angle, max speed analysis - hence the complicated braking in a corner when your entry speed exceeds the corner max speed (racing).

But on the street you are most likely going less than the max corner speed for your bikes max lean angle. You most likely won't speed up to the corners max speed. Instead what you do is keep going straight and at some point put the bike into it's max lean angle and when sufficiently pointed in the new direction pick the bike back up out of the turn. Let's say you a going 80 mph into a 200 mph curve - somewhere in the curve -the ideal spot being the apex, you execute an 80 mph max lean curve. Again no braking or acceleration required.

More practically though, you will be too afraid to put your bike at max lean (very wise), so you will slow to 60 mph, then do a 1/2 max lean turn at 60 mph in the middle of the curve. The bike still turns just as sharp it is just at 60 mph it only needs to lean 1/2 as much. While you slow from 80 to 60 you can get the bike to lean over for the curve and then get it stand up speeding back up to 80, which is safer and more fun too. Which if you notice is not braking before the corner !!!!!

The problem with the max lean angle turn, is if you get it wrong, you can't increase your turn without slowing down first (back to braking in the corner and now at your max lean which leaves very little braking).

Note you could have probably done the 200 mph corner at 80 mph and just not had such a sharp apex turn, or just as sharp an apex turn but a 3/4 lean. Again no brakes - so save your brakes for red lights, stupid drivers, deer, etc, etc when going straight unless you are going really, really too fast for the road - best to keep to the track for the really fast stuff and braking in the corners.
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Old 05-04-2013, 09:36 PM   #38
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Where can I read more about this, because it is counterintuitive.
Bernt Spiegel's book, The Upper Half of the Motorcycle: On the Unity of Rider and Machine has a great chapter on this. It might be available from your local public library via an interlibrary loan.
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So that circle for example if you have .6 of one and .7 of another you aren't at 1.3 as far as losing traction goes
No. It is the vector sum. As the diagram shows, from the circle to the center is 1.0g. Each yellow line starts out from more than 0.5g.
http://www.sparknotes.com/physics/ve...section2.rhtml
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Old 05-04-2013, 10:22 PM   #39
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One of the more lucid and informative threads I have come across in a while. Possibly due to the excellent tone set by the OP.

It seems apparent in the ethereal world of MotoGP that guys like Rossi and Crutchlow lost the front end at Jerez today while doing exactly this of moderating trail braking and extreme lean on greasy surfaces and fell prior to the apex. Of course, they are masters and were testing the limits of adhesion at the time.

I do brake but lightly in big turns but use gear resistance more and pay the suspension jinking penalty for it (R1200GS) but keep my sport riding at 7/10ths or less so trail braking is not really essential. I am going to work on it for smoothness and as a tool for emergency situations however which seem to be more relevant for snappy street riding than any timed or speed concerns with my style of cornering.

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Old 05-04-2013, 11:16 PM   #40
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Originally Posted by Jim Moore View Post
Either you're riding like a complete idiot, or you're trail-braking just for fun. There's really no in-between.
Well, I do it because I can, and I can play with my suspension more when I do it, check responses and rates and how the bike will move under me under changing loads. Do I need to? Of course not. But like anything you don't practice, you lose it. Since I don't get a whole lot of track time in, riding twisties is the place to practice.

The idea is not to ride the street at 10/10ths, it's to keep the muscle memory up so when you need to keep braking and then have a very controlled release, your hand does it for you. No panic grabs!

And it's fun.
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Old 05-05-2013, 03:39 AM   #41
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Originally Posted by atomicalex View Post
Well, I do it because I can, and I can play with my suspension more when I do it, check responses and rates and how the bike will move under me under changing loads. Do I need to? Of course not. But like anything you don't practice, you lose it. Since I don't get a whole lot of track time in, riding twisties is the place to practice.

The idea is not to ride the street at 10/10ths, it's to keep the muscle memory up so when you need to keep braking and then have a very controlled release, your hand does it for you. No panic grabs!

And it's fun.
I think we're in violent agreement!
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Old 05-05-2013, 07:53 AM   #42
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I'm a dickhead rider with 40+ years of on road riding experience who trail brakes into EVERY corner.

Thankfully it has worked for me so far and has saved me from many negative experiences.
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Old 05-05-2013, 08:16 AM   #43
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Originally Posted by Jim Moore View Post
It doesn't have a use at slower speeds, because it's a high-speed cornering maneuver. Here is the classic trail-braking scenario. You are coming up to a corner. You are braking as hard as you can. You waited so long to brake that you are still too fast for the corner at your tip-in point. In a very delicate and carefully timed maneuver you progressively ease off the brakes as you increase your lean angle, going right up to the edge of available traction. It's tricky, it's dangerous, and it frequently leads to crashes. I have a hard time believing my fellow paunchy, middle-aged faux adventurers are riding to that level on the street.


Just like rev matched downshifts, heel-toe in a car, or consciously applying countersteering to ever turn are all "high speed maneuvers?"

They all have one thing in mind -- knowing how to REALLY operate your machine to make it do what YOU want, when YOU want it to in the smoothest way possible. Race techniques absolutely apply to street riding, at ANY pace you want them to. You have an awfully narrow mindset on riding.
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Old 05-05-2013, 10:17 AM   #44
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Originally Posted by LuciferMutt View Post

Just like rev matched downshifts, heel-toe in a car, or consciously applying countersteering to ever turn are all "high speed maneuvers?"

They all have one thing in mind -- knowing how to REALLY operate your machine to make it do what YOU want, when YOU want it to in the smoothest way possible. Race techniques absolutely apply to street riding, at ANY pace you want them to. You have an awfully narrow mindset on riding.
Can you help me. I can't seem to find a corner on the street I can do this safely except for interstate on and off ramps. Most corners that I can go fast enough around legally to utilize the technique are blind enough to where if I am taking them safely I am going too slow to trailbrake into them.
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Old 05-05-2013, 11:02 AM   #45
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Can you help me. I can't seem to find a corner on the street I can do this safely except for interstate on and off ramps. Most corners that I can go fast enough around legally to utilize the technique are blind enough to where if I am taking them safely I am going too slow to trailbrake into them.
Not sure if you are just being sarcastic to evoke something... but

It's easy to practice this technique in an empty parking lot. That's where the MSF ART is taught and so are Lee Parks Total Control classes.

In the ART, it's basically a relatively small diameter circle (75') marked by cones. Use 1 of the cones as a 'cue' to start trail braking, another cone for the 'apex' and yet another as the 'exit'.

When we did it, the cue cones took up a total of about half the circle. So there were a lot of repetitions of doing this. It resulted in a pretty great feeling about how stable the bike can feel when cornering with this technique, very stable when you're smooth with the controls.

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