Trail Braking from the Classic, Vintage & Veteran forum
21 - 40 of 79 Posts
Joined
·
58 Posts
Interesting analysis of trail braking, making some good points. I think the assertion that more rake changes the direction of forces on the tire is completely incorrect. Inescapable and inflexible laws of physics don't allow for such "magic". I'd also challenge your conclusion. You may have some limitations due to having less precise control over brakes, less powerful brakes and different tires on older bikes but these limit braking under all circumstances, not only trail braking.Hi Trumpkin
‘Not for us’ is the phrase that comes to mind, it’s a modern technique for modern bikes:
Tyres:
You will be braking/steering and leaning at the same time, you need the tyres to be sticky and preferably getting progressively stickier towards the outer edge, you also need pliable sidewalls to ‘increase the contact patch under load’. Unless you have upgraded to radial tyres then you are at much greater risk of the front tyre sliding away. The thin Cross ply tyres fitted to Classics just don’t cut it for trail braking.
Brakes:
You need good feedback to the lever and fingertip control, the standard wooden paddle ‘on or off’ disk brake fitted to T140’s does not give you enough control, it it will be so easy to approach the wheel locking point without noticing. Self servo drum brakes-no chance far too aggressive .
Unless you have made some serious upgrades to the front brakes, standard Classic Triumph brakes they just don’t cut it for trail braking.
Rake:
One of the fundamental principles of trail braking is to use the downforce created by braking to increase the grip of the front tyre. The long rake of these old frames will tend to push the brake forces more froward, rather than downward like steep head angled modern bike will do. So instead of pushing the tyre into the ground, the tendency is to push the tyre forwards, making it skid. Classic bike frames just don’t cut it for trail braking.
Trail braking is for R6’s, etc. Modern sports bikes-even then many sports bike riders have been down the road on their arses trying it. You also need practice; perhaps if you can do 10 stoppies in a row, with the rear wheel at least 3 feet in the air, then you are ready to try trail braking to increase your corner speed. It can be done, but you might find ‘slow in fast out’ might be a safer and quicker riding technique for classics.
Good luck
let me know where you want the flowers sent>
Regards
Peg.
Trail braking may be a new concept to you but it is not a modern skill that only applies to modern vehicles. It is as old as the invention of brakes.
Joined
·
58 Posts
If you are going slow enough into a corner, you don't need to brake at all of course. However, for a normal corner, I would suggest practicing gently easing off braking as you add lean until it becomes your normal practice. Also, in a hard/fast turn (not necessarily on the track) try not to complete easing off the last bit of brake until you are beginning to slowly open the throttle.
Joined
·
47 Posts
I have seen this thread for some time, but took no interest in it because I thought it was something to do with trail bikes.
Now I realise it is to do with use of brakes on road bikes. Homer "Doh".
It is still not obvious to me why the word "trail" is used?
The method seems to be what any experienced rider with commonsense would use, that you can only brake most heavily in a straight line and must be much more careful with use of front brake especially at angles of lean. What is new?
Is it something to do with getting every last millisecond in a race of high preformance bikes on a racetrack? If so I don't see what it has to do with our old bikes on the road, if you are doing that then I think you are a dangerous road rider.
You do not know what you will find round that corner, if you are already 100% committed you will have no controllable options available to yourself or another person. That is irresponsible. That is what racetracks are for.
Now I realise it is to do with use of brakes on road bikes. Homer "Doh".
It is still not obvious to me why the word "trail" is used?
The method seems to be what any experienced rider with commonsense would use, that you can only brake most heavily in a straight line and must be much more careful with use of front brake especially at angles of lean. What is new?
Is it something to do with getting every last millisecond in a race of high preformance bikes on a racetrack? If so I don't see what it has to do with our old bikes on the road, if you are doing that then I think you are a dangerous road rider.
You do not know what you will find round that corner, if you are already 100% committed you will have no controllable options available to yourself or another person. That is irresponsible. That is what racetracks are for.
I don't know either, until I actually read one of these threads I always thought it referred to dragging rear brakes, I guess because trailers are in the rear :dunno
That's not how I think of it. I don't think I enter the corners any faster really, just sometimes I remain lightly on the front brake and off the gas as I enter a corner I can't see through, to give me more options once I can see what's past the apex. I use it as more of a safety thing than a performance thing.
It sucks when you think you braked enough for a corner and start rolling on the throttle, only to realize too late your should have braked more. This trailing the front brake even after lean in gives you longer to make that assessment.
It seems you are challenged with reading and comprehension as you admit. Try reading the whole thread and opening some of the links to Youtube and you'll see a fairly consistent endorsement of the technique for safer riding.
Your evaluation is not correct. Read the thread .
Old school teaching maintained zero use of brakes during cornering.
Racing technique has filtered down to everyday usage though many were already using the Front brake this way from personal experience.
Many here have now explained very well the method of feathering the brake into the corner and trailing it off as you increase your lean. This changes the bike geometry by loading the forks and also spreads the tyre making more rubber contact on the road.
That's why it's called trail braking, because you trail off.
But please don't take my brief summary , do as I said and read it all and watch the videos.
I am going to start to learn this at my old age after a lifetime of never even knowing about it.
It's not about going as fast as possible at all.
Joined
·
58 Posts
When I started riding, being from an area of the UK where every road is twisty and every corner has varying radius and camber, it was fairly natural to be adjusting brake pressure as you entered a corner and began leaning. With hindsight, my braking technique could have used improvement but I was definitely trail-braking as my normal riding practice.
A few years later, living in USA and learning to become a MSF Ridercoach, basic rider training strongly emphasizes braking as you approach a turn so you are fully slowed to suitable speed, before leaning over and getting on the throttle as you enter a turn. The reason for this is (largely) because most brand new riders do not have the fine motor skill to trail brake effectively but DO often run wide and off the road or into oncoming traffic as a result of entering a corner too fast - too fast for their ability anyway. As an instructor, it becomes a lot easier to demonstrate techniques that you, yourself, use all the time so I adopted this technique (mostly) for my own riding. It may not be the absolute quickest way round a corner but it's the safest and it encourages the development of fine control for acceleration through a corner.
Fast forward a little further to advanced training that reintroduced trail braking as a worthwhile skill. I began reapplying it to my everyday riding, with worthwhile effect. With the benefit of lots of practice, I had no problem reverting to braking before a turn when demonstrating basic skills.
Most recently, in an effort to fine tune my own riding a bit more, I have started on an Institute of Advanced Motorcyclists course in the UK. Guess what? They use a very good riding strategy for dealing with hazards that emphasizes adjusting your speed BEFORE you reach a hazard (such as a turn), then accelerating through it. While I'm certainly getting a lot from the training, I am having to switch back to braking before entering corners as even the lightest trail braking leaves the brake light on, signalling that I am not following the strategy to the letter.
IAM training is based upon British Police 'Roadcraft', which is, arguably, the best approach to safe street riding in the world. If you've ever followed a decent British police motorcyclist and tried to keep up with their smooth, relaxed looking pace, you'd be hard-pressed to do much better. I would suggest, therefore, that while trail braking could be incorporated into and add to any rider's skill-set, it does not confer a significant advantage on the street and is not an essential skill for a good, safe, quick street rider.
A few years later, living in USA and learning to become a MSF Ridercoach, basic rider training strongly emphasizes braking as you approach a turn so you are fully slowed to suitable speed, before leaning over and getting on the throttle as you enter a turn. The reason for this is (largely) because most brand new riders do not have the fine motor skill to trail brake effectively but DO often run wide and off the road or into oncoming traffic as a result of entering a corner too fast - too fast for their ability anyway. As an instructor, it becomes a lot easier to demonstrate techniques that you, yourself, use all the time so I adopted this technique (mostly) for my own riding. It may not be the absolute quickest way round a corner but it's the safest and it encourages the development of fine control for acceleration through a corner.
Fast forward a little further to advanced training that reintroduced trail braking as a worthwhile skill. I began reapplying it to my everyday riding, with worthwhile effect. With the benefit of lots of practice, I had no problem reverting to braking before a turn when demonstrating basic skills.
Most recently, in an effort to fine tune my own riding a bit more, I have started on an Institute of Advanced Motorcyclists course in the UK. Guess what? They use a very good riding strategy for dealing with hazards that emphasizes adjusting your speed BEFORE you reach a hazard (such as a turn), then accelerating through it. While I'm certainly getting a lot from the training, I am having to switch back to braking before entering corners as even the lightest trail braking leaves the brake light on, signalling that I am not following the strategy to the letter.
IAM training is based upon British Police 'Roadcraft', which is, arguably, the best approach to safe street riding in the world. If you've ever followed a decent British police motorcyclist and tried to keep up with their smooth, relaxed looking pace, you'd be hard-pressed to do much better. I would suggest, therefore, that while trail braking could be incorporated into and add to any rider's skill-set, it does not confer a significant advantage on the street and is not an essential skill for a good, safe, quick street rider.
I made this post https://www.triumphrat.net/riding-and-survival-skills/950294-trail-braking.html
about it a few months back. There's a pretty good discussion in that thread, including from Misti Hurst who is a riding coach with Keith Code's California Superbike School.
I think it is a fantastic technique, but not useful all the time.
Check out the video's that were posted in that thread, also the interview that Misti posted with Keith Code.
about it a few months back. There's a pretty good discussion in that thread, including from Misti Hurst who is a riding coach with Keith Code's California Superbike School.
I think it is a fantastic technique, but not useful all the time.
Check out the video's that were posted in that thread, also the interview that Misti posted with Keith Code.
No single “ technique “ should be used all the time. Road conditions are always taken into consideration by all riders, regardless of skill level. If you didn’t vary your riding technique, whatever it is, you wouldn’t be reading this post. My riding technique no doubt changed when I lost an eye, resulting in no depth perception. My “post-loss” riding needed to take into consideration that I might discover mid turn that I’m going too fast or braked too little or too late. Trail braking is especially useful on curves with a changing radius. On a disc brake Triumph you might find it easier to operate the front brake if you lower the fluid level in the front brake reservoir so that you gain some lever travel , especially if your hands aren’t large. It’s much easier to modulate braking when your hand isn’t spread open.
Joined
·
1,734 Posts
Please enlighten me on how changing the direction of the input force does not change the direction of the resultant reaction from the contact patch, I would love to know.
I always thought Newtons third law, trigonometry and vectored forces were ‘magic’ thing that could not possibly be understood, best I stick to cooking, cleaning and painting my fingernails.
Why do you think it’s a new concept to us, just because you have blundered onto a classic forum, don’t assume we are all luddites.
Peg.
I took to trail braking as soon as I read about it. "How about that? It works!" The same as 40 years ago when I first read about counter-steering in the gov't's motorcycle rider's instruction material for getting my motorcycle endorsement on my licence...
Joined
·
58 Posts
The front tyre doesn't know what angle the forks are at. It experiences forces due to weight in the vertical direction, braking in the fore and aft direction and cornering forces dependent on speed, corner radius and lean angle. Changing the rake of the fork may affect how some of the forces affect the suspension or steering head but not the tyre.
Your nails look fine I'm sure.
I assumed no such thing. I feel into the trap of trying to correct something on the internet. I should know better. Sigh!
You did better than me, I thought that was a misprint. 6,000 miles later I finally got some training and realized what counter-steering was. That helped
Joined
·
1,734 Posts
Hi Slarditbartfast
I didn’t think I would find someone with a profile name stranger than mine:grin2:
Under heavy braking close to or at wheel lock, you can consider the wheel as an extension of the fork. Visualise it as a stick with a rubber skid pad on the end, because this is how it will act.
As the brakes back off this concept reduces progressively until we are eventually back to the tyre rolling free and not knowing what angle the forks are at.
If we go back to the stick with a rubber pad on the end visualisation at the wheel lock position. If you hold the top end of our virtual stick close to the ground and push forward, the rubber pad will skid along the ground. If we now hold our virtual stick at a steep angle it will try to dig into the ground.
This is how the forks and wheel will react during braking.
The tyre contact patch under braking will push forces into the ground, force has two properties magnitude and direction, force is a vector quantity. The magnitude is varied by the resistance supplied by the brakes, the direction is determined by the angle of the forks.
The equal and opposite reaction from the ground will push back along the fork, the force will be used to a) retard the bike and b) transfer load on to the fork. The proportion with which this is shared out depends on the fork angle (low stick vs high stick).
A steep fork angle will load the tyre more than a shallow angle, the grip of the tyre results from pressure x contact area x coefficient of friction between the two surfaces. The pressure x area effectively cancel each other out, so grip can be thought of as force x CoF.
A steep angled fork will give a greater percentage of force to tyre load, resulting in more grip, allowing more brake force to be applied without skidding.
Sports and modern bike react to differently to braking than classics (or cruisers) due to their suspension geometry. You can brake harder and deeper with a more modern setup, due to the high grip tyres having a greater a load imposed upon them.
When you couple the classic bikes lower tyre loading with low feedback early design hydraulic and self servo drum brakes, plus low grip/low sidewall flex tyres (There is a strong rumour that DuPont stole the formula for Teflon from the Avon SM tyre compound). You have a good recipe for impending doom while trying to brake while leaned over.
(I have not even mentioned crude suspension that fails to keep the tyre on the ground half of the time.)
At one time trail braking was considered an advanced technique, for good reason.
Advances in tyre/suspension/brake/frame and tyre design now mean that it now a mainstream riding technique.
The way we ride is changing.
The one thing not mentioned so far in this thread and possibly the greatest safety advance since the crash helmet, compulsory ABS (in Europe at least) if you mess up on a modern bike, there is a pretty good chance the bike will rescue you. The old clunkers will let you eat dirt.
Regards
Peg.
I didn’t think I would find someone with a profile name stranger than mine:grin2:
It wasn’t trying to correct something on the internet, it was slipping in a condescending phrase into you original post that provoked a well deserved reaction.
My nails look like a relief map of the moon, the fashion here is to paint white tips on the nails, I have ancient Triumphs so I get black nail tips :frown2:
The above is perfectly true for a rolling wheel and suspension, but please consider that the relationship between the wheel and forks change under braking.
Under heavy braking close to or at wheel lock, you can consider the wheel as an extension of the fork. Visualise it as a stick with a rubber skid pad on the end, because this is how it will act.
As the brakes back off this concept reduces progressively until we are eventually back to the tyre rolling free and not knowing what angle the forks are at.
If we go back to the stick with a rubber pad on the end visualisation at the wheel lock position. If you hold the top end of our virtual stick close to the ground and push forward, the rubber pad will skid along the ground. If we now hold our virtual stick at a steep angle it will try to dig into the ground.
This is how the forks and wheel will react during braking.
The tyre contact patch under braking will push forces into the ground, force has two properties magnitude and direction, force is a vector quantity. The magnitude is varied by the resistance supplied by the brakes, the direction is determined by the angle of the forks.
The equal and opposite reaction from the ground will push back along the fork, the force will be used to a) retard the bike and b) transfer load on to the fork. The proportion with which this is shared out depends on the fork angle (low stick vs high stick).
A steep fork angle will load the tyre more than a shallow angle, the grip of the tyre results from pressure x contact area x coefficient of friction between the two surfaces. The pressure x area effectively cancel each other out, so grip can be thought of as force x CoF.
A steep angled fork will give a greater percentage of force to tyre load, resulting in more grip, allowing more brake force to be applied without skidding.
Sports and modern bike react to differently to braking than classics (or cruisers) due to their suspension geometry. You can brake harder and deeper with a more modern setup, due to the high grip tyres having a greater a load imposed upon them.
When you couple the classic bikes lower tyre loading with low feedback early design hydraulic and self servo drum brakes, plus low grip/low sidewall flex tyres (There is a strong rumour that DuPont stole the formula for Teflon from the Avon SM tyre compound). You have a good recipe for impending doom while trying to brake while leaned over.
(I have not even mentioned crude suspension that fails to keep the tyre on the ground half of the time.)
At one time trail braking was considered an advanced technique, for good reason.
Advances in tyre/suspension/brake/frame and tyre design now mean that it now a mainstream riding technique.
The way we ride is changing.
The one thing not mentioned so far in this thread and possibly the greatest safety advance since the crash helmet, compulsory ABS (in Europe at least) if you mess up on a modern bike, there is a pretty good chance the bike will rescue you. The old clunkers will let you eat dirt.
Regards
Peg.
Joined
·
677 Posts
LOL...
One of my most embarrassing get-offs occurred in the mid-70s. Just after passing a couple of well-known US motorcycle journalists on my Ducati 450 Desmo I trail-braked right to the traction limit. Unfortunately I went a bit too far, the K-81s let go, and I was almost run over by both of them
Joined
·
58 Posts
Magic? Not meant that way - sorry!
Stick with a rubber pad -like it. Still disagree with the analysis, however. Forces are not somehow directed straight along the forks. In your analysis you are suggesting that (in an extreme case) horizontal forks would result in tyre forces as if the bike had no weight and vertical forks would result in tyre forces as if the bike was not braking. Forces at the steering head are related to the weight and inertia of the bike. These will be transmitted through the forks (regardless of their angle) to the contact patch of the tyre. If the wheelbase and centre of mass of two bikes are the same, and they are travelling at the same speed, braking equally hard, the forces at the front and rear tyre patch will be identical. Different fork angles or suspension design may change how the bike handles but they can't change the forces at the tyre unless they change the wheelbase too. I owned a GTS1000 for many years. It has no forks in the conventional sense and all braking forces are directed straight into the front swingarm. The bike still has weight (a lot of it) however, and while the feel and performance of the suspension is somewhat unique, the tire sees the same forces (and trail braking works just the same as does not trail braking.)
As I noted earlier, all these modern advances allow harder braking under all circumstances, including while leaned over in a corner. They may also give better feel, allowing you to trail brake smoother and closer to the limits. Trail-braking as a discipline and topic for discussion may also be "modern" but the practice is as old as the first two-wheeled vehicle with brakes. I had never heard of the concept when I started riding bicycles in the 60's or motorcycles in the 70's but I can assure you I was doing it. It was only when I re-started teaching in the early 2000's that I encountered a curriculum that encouraged NOT braking in a corner (for beginners on bikes with powerful brakes.)
True, although I don't think many people will actually activate ABS while leaned over in a corner. Unless you're on the track, trail braking at the threshold of tire grip in a turn is most definitely a very advanced practice, requiring great skill and optimal track conditions. However the application of SOME trail braking by street riders under normal road conditions is and was a relatively basic skill, requiring only moderate finesse of the controls, regardless of whether on a modern sport bike, cruiser or vintage machine.
21 - 40 of 79 Posts
Join the discussion
Join now to ask and comment!