Talk:Trail braking
Motorcycle Trail Braking
[edit]Subjective Opinion
[edit]There is a lot of information in this article that has no attribution such as a quote from Valentino Rossi and some really questionable statements about "braking causes a motorcycle to 'stand-up'" that are not entirely true or accurate and can vary from motorcycle to motorcycle. Realizing this is a very controversial topic among motorcyclists, particularly for those who advocate older riding styles, such as those taught by Kieth Code compared to newer, more modern riding techniques such as those described in Nick Ienatsch's book, Sport Riding Techniques.
As is the case with many riders, there is a tendency to express "how I ride", straying away from credible, known riding techniques. (one such example is not using the rear brake. This is opinion not a credible riding technique). Caution should be used when editing this page to not include personal biases.
It is interesting to note that the first "A Twist of the Wrist" book, written in 1983 was the first to discuss and illustrate Trailbraking, pages 64, 65 & 66. The trailing off of the brake and its ability to maintain suspension stability is illustrated in 6 photos of Eddie Lawson entering the corkscrew at Laguna Seca in that same old book, pages 74 & 75. The question of what is new and what is old technique is an intersting one but has no relevance to describing what the technique consists of. Keith Code — Preceding unsigned comment added by 99.27.104.247 (talk) 18:49, 24 July 2012 (UTC)
Additional trailbraking references in the "A Twist of the Wrist" books are on pages 35, 36, 51, 62, 63, 64 and 66 of Twist 1. Twist 2, 1994, references are on pages 59, 71, 75 and 103. References to Trailbraking in "The Soft Science of Roadracing Motorcycles", 1986, are on pages 94, 97 and 142.
Thoughts
[edit]Article states that on a motorcycle you hold both front and rear brakes until apex. This is slightly faulty, since there are many motorcycle riders (even racers) who never even touch the rear brake at all.
Misc (Please separate and label your comments yourself, so other people don't have to)
[edit]Although I appreciate the time the original authors took to write it, this article is problematic in many ways, including factual accuracy. (Hence the "disputed" stamp) Below are some issues I have with this article:
- "Advanced technique"? Perhaps, but seems slightly POV to me. I won't object to a reinsertion of this term if there is consensus among some experts on this.
- "Requires professional training"? No. This implies that one cannot trail brake unless professionally trained, which is untrue.
- "Meaning to continue to brake into a turn" Accurate, but poorly worded
- Dragging brakes to me implies a force so slight as to not produce any effective braking.
- Purpose is to stabilize? No, but it can keep suspension from rebounding and unsettling the bike
- Make ready for unpredictable circumstances? No. Many people trail brake on a fully visible, empty racetrack. It makes the front stick better by keeping weight to the front.
- "Front and rear brakes" are not required for trail braking.
- Opening the throttle is not a required step in this, and I'm unsure if that was intentionally implied or not.
- How does trail braking "stabilize" the "frame" of the bike?
I found what I read of the outside-linked article on trail braking to be informative and accurate, and I hope to someday find the time to edit this article up to those standards. --Mud4t 01:46, 29 March 2006 (UTC)
- I believe that all these objections are now satisfied, and so I am removing the "disputed" tag. -AndrewDressel 16:39, 13 August 2006 (UTC)
Inaccurate and complicated use of the term.
[edit]The term "Trail-braking" has been used for many years in regards to motorcycles and cars. It is not specific to motorcycles and it is a very simple technique used quite often in all motor-sports.
"Trail" is from the verb, meaning to tow, or drag something behind, like a trail-er. Thus the term, "Trail-braking" = braking after you turn. Or if you prefer, dragging the brake after you turn: Continuing to apply the brake(s) after turning into a corner.
There is no degree of pressure. No rule about when you stop using the brake. It has nothing to do with the use of front or rear brake. There is nothing else associated with this term, except for how it is used, the benefits of it's use, the consequences of it's use.
The term is simple: Continue to brake after turning into a corner. That is all the term means. No more. No less.
Skippy Stone 06:57, 12 November 2007 (UTC)
MC to do list/GA
[edit]Added to MC do do list. Potential Good article.
Controversy
[edit]I deleted "There is no actual controversy, countersteering is necessary to change direction. And per the laws of Angular Acceleration above, the machine can negotiate a tighter turn as speed is decreased," added by Keith code (talk · contribs). For one thing, it is uncited, and it contradicts the paragraphs above it.
This section probably needs to be revised, and maybe have the title changed from "Controversey" to something else, but you can't have a section that starts off saying there is a controversy and then ends by saying there is no controversy.
Please discuss and settle the question on the talk page, then edit the article to make a consistent statement. --Dbratland (talk) 17:34, 10 March 2010 (UTC)
Wrong statement
[edit]The article says that
- If the motorcycle is leaned over, forces from the front brake and the deceleration causes the motorcycle to yaw (lean), while use of the rear brake generates a torque that tends to align (straighten) and stabilize the motorcycle.
That's completely wrong. If the motorcycle is leaned over and you use the front brake then the motorcycle will straighten/stand up. And using the rear brake while cornering will lean motorcycle more. That's how the brakes work during cornering and that was tested using my personal motorcycle a lot of times. —Preceding unsigned comment added by 77.35.23.28 (talk) 05:12, 15 March 2010 (UTC)
- Any tensioning of the chain (by acceleration or rear trail braking) will cause the chain to want to minimise distance between the rear sprocket and the front sprocket, thereby squashing the suspension, and lowering the rear. When the rear is lowered, the steering geometry of the bike becomes less responsive, tending to want it to stand up and go wide in the corner. Trail braking with the rear brake will therefore do this (although it will also transfer weight forward, perhaps nullifying the effect of lowering the rear by squashing the forks - I am not sure to what extent, or which effect will be greater). Trail braking with the front brakes will transfer weight forward, making steering geometry more responsive (but also loading up the front wheel traction more, so the limits of traction will be reached quicker).
- Trail braking with the rear pre-loads the rear suspension by squashing it, thereby making it feel more "stable". So there are good and bad points for rear and front trail braking.
- As regards the controversy between trail barking and counter steering: these are not issues that run counter to each other at all. Counter steering is for changing the angle of lean in corners, and setting the bike into the lean initially. Trail braking does not actually cause lean, but will affect how quickly the requisite lean is achieved, by changing the steering geometry (or "flickability"). Accordingly, these are not counter topics at all. —Preceding unsigned comment added by 203.96.117.138 (talk) 03:20, 2 March 2011 (UTC)
- I've asked for clarification:
- On what page does Cossalter, the cited source, discuss this?
- Is "yaw (lean)" supposed to mean "lean is another way to say yaw", because that is not correct, or "yaw and lean", in which case why not just say "yaw and lean"?
- Is "align (straighten)" supposed to mean "lean less", "steer less", "pitch less", "decrease understeer", "decrease oversteer", some combination of the preceding alignments and straightenings, or something else?
- I cannot find answers to these questions in the existing article or the responses above. -AndrewDressel (talk) 12:26, 2 October 2018 (UTC)
Excess and contradictory detail in intro
[edit]The main reason I moved this content from the intro to the Driving section is that it is clearly written specifically about cars, and it contradicts the Motorcycling section. It doesn't make any sense at the top of the article. Even in a driving-only context, sources like Bonduarnt and Newton mention other reasons for trail braking besides the two which are claimed to be the only reasons. It's good to keep in mind that a term like 'trail braking' isn't just used by one kind of car. It's also used for go cart racing, motorcycles, and other kinds of vehicles with different properties. If you're specifically talking about driving sports cars on a track, then say so so it's clear what the context is. --Dennis Bratland (talk) 04:22, 29 March 2018 (UTC)
- Wikikpedia articles are not driving instructions. If you’re worried that the article’s intro doesn’t adequately instruct drivers on trail braking technique, it’s because it isn’t supposed to. See WP:NOTHOWTO. Also, this article isn’t only about cars. —Dennis Bratland (talk) 16:06, 30 March 2018 (UTC)
Confusing sentence
[edit]"If the motorcycle is leaned over, forces from the front brake and the deceleration causes the motorcycle to yaw (lean), while use of the rear brake generates a torque that tends to align (straighten) and stabilize the motorcycle.[7][clarification needed]"
1.I can't see where this is covered in the reference [7] Cossalter Motorcycle Dynamics.
2.Terms lean and yaw are different.
Bike lean involves a rotation about the roll axis (front to rear), with a roll centre being below the ground for a given bike,rider,rate of turn and turn radius. Yaw is a twist or rotation as seen in a plan view. [TF p.3-22]
When leaned over the contact patch moves from the mid point to the inside of the tyre profile. Applying the brakes creates a torque force turning the wheel more into the turn, which will tend to reduce lean angle i.e. upright the bike. e.g. in a left steady state turn with lean, applying the brakes will torque the steering anti-clockwise ...which increases the centripetal force for that rate of turn thus tipping the bike outwards...i.e. straightening it up. [TF P14-10]. At the rear wheel braking creates a torque that yaws the frame into the turn applying a lateral force on the steering axis which also turns the wheel into the turn. [TF P14-10].
TF: Tony Foale Motorcycle Handling and Chassis Design - The Art and Science 2002
Rear brake application will alter squat position and typically should tend to straighten the swing arm angle slightly increasing wheelbase and rear wheel trail and front wheel trail.. . Some frame designs aim to minimise squat so reducing this effect. — Preceding unsigned comment added by Tulipacerebri (talk • contribs) 15:35, 24 July 2019 (UTC)