[HN Gopher] Countersteering
___________________________________________________________________
Countersteering
Author : Lio
Score : 96 points
Date : 2022-09-14 08:04 UTC (14 hours ago)
(HTM) web link (en.wikipedia.org)
(TXT) w3m dump (en.wikipedia.org)
| jpe90 wrote:
| When you lose traction in your car from rain or snow, your
| instinct is probably to countersteer, but you should instead
| steer into the turn and countersteer when you regain control.
|
| I can't remember if they actually taught that in driving school,
| but my dad had me deliberately lose traction repeatedly in a
| parking lot in the snow to get the hang of it. It saved my life a
| few times because I was a reckless idiot as a teenager.
| arghwhat wrote:
| The proper response depends on the type of traction loss. What
| you describe is the appropriate response for understeering, but
| will amplify oversteering. Although to be fair, considering how
| common front wheel drive is these days, understeering is what
| us most likely to occur, and the proper response of following
| the failure is less intuitive than counter steering.
|
| On a "proper" 4x4 sliding, increasing throttle will often
| straighten the path of the vehicle irrespective of current
| steering input - a fun quirk of locking differentials.
| mellavora wrote:
| > increasing throttle will often straighten the path of the
| vehicle irrespective of current steering input
|
| "when in doubt, gas it out"
| tbyehl wrote:
| "Full throttle will either solve the problem or end the
| suspense."
| HPsquared wrote:
| Even understeering, to recover grip you need to reduce the
| load (slip angle) on the front tyres- by straightening the
| wheel a bit. Not turning the wheel even further. So the same
| general principle applies, but it's less urgent when
| understeering as it's a kind of 'stable' situation.
| deelowe wrote:
| Explanations help somewhat, but there needs to be some
| intuition for these principles to be applied effectively. I
| highly recommend going to a few auto cross events truly get
| it. Learning what it's like when "steering gets light" and
| how "turning into the skid" recovers it is really something
| you need to learn by feel.
| Hamuko wrote:
| > _On a "proper" 4x4 sliding, increasing throttle will often
| straighten the path of the vehicle irrespective of current
| steering input - a fun quirk of locking differentials._
|
| Just remember when you're not driving a four-wheel drive car
| if you learn to rely on this method.
| tapland wrote:
| I didn't see that in us driving ed but it's a mandatory (and
| practical) part of the Swedish one
| VBprogrammer wrote:
| We don't get enough snow here, particularly in the south of
| England, for me to to be a particular expert in driving in the
| snow but I don't think turning into the turn makes any more
| sense. The main aim is to try to get the wheels back in the
| state where they are experiencing rolling friction rather than
| sliding friction. Usually by opening the steering.
| mod wrote:
| I believe you're saying the same thing.
| KennyBlanken wrote:
| Your car understeering or oversteering is not countersteering.
|
| Steering inputs to correct for understeer and oversteer are not
| countersteering.
|
| Countersteering is specific to two-wheeled vehicles. Please
| read links before commenting...
| thrwyoilarticle wrote:
| Did you see where the link says:
|
| >For the technique with a similar name used in automobiles,
| see Countersteering (Automobile).
|
| ?
| pessimizer wrote:
| The sentence that makes it completely clear that the
| article isn't about what is often called "countersteering"
| in automobiles?
| thrwyoilarticle wrote:
| The sentence that implies it's not limited to two wheeled
| vehicles
| ehnto wrote:
| Although you're right, and we're talking about different
| things in the article, it's still called countersteering when
| you correct an oversteering car.
| bborud wrote:
| > When you lose traction in your car from rain or snow, your
| instinct is probably > to countersteer, but you should instead
| steer into the turn and countersteer > when you regain control.
|
| I'm not entirely sure I understand. Perhaps some context is
| missing?
|
| One key question is: when was this and in what car?
|
| Most modern cars have various forms of stability control
| systems that try to execute the driver's _intent_. So for
| instance my daily driver is vastly different from my 1980s
| plaything that doesn 't have any driver's aids. On slippery
| surfaces they require completely different approaches to
| driving when you are on, or over, the grip limit.
|
| If you are trying to work with the stability control system,
| yes, you probably need to communicate your intent to the car
| and let it take care of things. But I'm not sure "don't
| countersteer" is necessarily good general advice because it
| really, really depends on why/how you lost traction and how the
| car will react. The only way you can know that is to take it
| onto a slippery track (or a large open space) and try it out.
|
| Also, stability control systems can (and do) fail. They can
| shut down due to sensor errors or, if you buy a sports car,
| there may be an option for shutting them off partially or
| completely.
| exDM69 wrote:
| The article was about bicycles and motorcycles, not opposite
| lock countersteering in a car.
|
| I don't know what exactly you mean by "losing traction"
| (understeer or oversteer) but your advise does not sound
| correct to me.
|
| But when you get into an oversteer situation in a car, the
| aligning moment acting on the tyre contact patch will
| automatically counter steer the front wheels to the outside
| corner (assuming the fronts still have grip).
|
| The correct response to oversteer is opposite lock (counter
| steer) to the outside (not to the inside!) and rapid recovery
| (center the steering wheel) when the car starts to correct
| itself. In a front wheel drive car, some throttle can help to
| correct the oversteer faster but it can also induce a really
| bad tank slapper pendulum and you shouldn't do this in public
| roads. In a rear wheel drive, if the reason for the oversteer
| is too much throttle (power slide), easing off the throttle
| will correct it. But getting off the throttle quickly (esp if
| you're not power sliding) can also induce lift-off oversteer
| and make the oversteer worse.
|
| In an understeer condition, just easing gently off the steering
| and the throttle will usually correct the situation but doing
| it too quickly can induce a tank slapper oversteer (from lift
| off oversteer), which you need to correct by counter steering.
| It sounds like this is the scenario you're describing, but you
| should definitely not apply more steering input in this
| situation.
|
| In a road car you will almost never get to an oversteer without
| deliberately inducing by power sliding, hand brake, scandi
| flick or other rally driving moves (or accidentally in the case
| of a bad recovery from an understeer). Road cars' vehicle
| dynamics are set up to be very understeering through mass
| distribution and suspension set up.
|
| My driver's education had two full days of skidpad training in
| slippery conditions. Opposite lock was the response that they
| taught for oversteer (which the instructor induced by pulling
| the hand brake in a turn). I also used to do a lot of parking
| lot snow drifting back when cars didn't have nanny electronics
| to prevent it. On top of that I have done lots and lots of
| simulator racing, both track and rally.
| dwringer wrote:
| What you describe is what we were taught in drivers' ed as
| "steer into the direction of the skid". If your back end is
| whipping out (oversteer) then turn to the outside (the
| direction the wheels are skidding). If your front end is
| lagging into a turn (understeer) turn again toward the
| outside, which is the direction the wheels are skidding and
| will straighten them out to regain traction.
|
| Maybe that's what OP meant by "into the turn" (although as
| you point out, that is actually toward the outside of the
| turn).
| superice wrote:
| This Veritasium video touches upon the same phenomenon:
| https://www.youtube.com/watch?v=9cNmUNHSBac
| ho_schi wrote:
| And also Sheldon Brown:
|
| https://www.sheldonbrown.com/brakturn.html
|
| The writings of Sheldon Brown are somewhat a Wiki for cyclists
| teaching maintenance and riding a bicycle. I've learned riding
| a bicycle as child but the theory and maintenance guides are
| useful to know.
|
| If you are German you may also appreciate Wikipedalia:
|
| https://wikipedalia.com
| KennyBlanken wrote:
| FYI Sheldon Brown passed many, many years ago and the site
| has gone downhill since. The current "editor" has been
| replacing and adding content but has little to none of the
| practical knowledge Brown had from working in a bike shop for
| decades.
|
| A lot of content is now merely the new editor's opinions,
| quite a bit of it is bullshit, and sadly people treat it as
| authoritative because Brown's name is so strongly associated
| with it.
| Chris2048 wrote:
| Who is the new editor? John Allen?
| freetime2 wrote:
| > Skilled cyclists use the front brake alone probably 95% of
| the time
|
| I am skeptical about this claim. Here's a recent video by a
| former pro on the subject of braking, for example, and he is
| squeezing on both brakes at the same time in most of the
| shots. [1] He does say that the front brake can be squeezed a
| lot harder, though, and is source of most of your braking
| power.
|
| Even in the places where Brown says you _should_ use the rear
| /both brakes comprise much more than 5% of my total brake
| usage: bumpy roads, slippery roads, long descents, breaking
| during a turn, etc. But I'll also use both breaks to come to
| a stop pretty much any time I'm coming up to a traffic light
| or other non-emergency stop.
|
| [1] https://youtu.be/wX4tFn4RzrU
| ho_schi wrote:
| Thank you! You're right with the critique. The number is
| wrong and an exaggeration. To be fair, Brown did focus on
| emergency breaking and the paragraph lists situations for
| the rear break.
|
| The video is good and states that the front brakes matters
| most for emergency breaking. Breaking well planed before a
| turn, because breaking in turn can lead to loose of
| traction and result in skidding. Brown mentions this also
| as situation for gently breaking with front- and back break
| together to avoid skidding. I think most important is the
| rule to break gently in regular situations.
|
| As you I'm breaking often with the rear break only, on
| bumpy roads or when I need little deceleration. And often
| with both! Sometimes also in change during step descents
| (allow cool down of front break). I once didn't notice the
| bumpy surface (asphalt looked well) before a turn on a step
| decent and used only the front break, it was horrible
| because lack of deceleration and every bump was a hit into
| the handlebar.
| heavenlyblue wrote:
| > I am skeptical about this claim. Here's a recent video by
| a former pro on the subject of braking, for example, and he
| is squeezing on both brakes at the same time in most of the
| shots. [1] He does say that the front brake can be squeezed
| a lot harder, though, and is source of most of your braking
| power.
|
| Note that he's stopping with both brakes and also moves his
| hips behind the seat, which makes tumble-forwards situation
| less likely. If you have enough strength you can go so low
| in that position that you will also slide on the front
| wheel as well on the back wheel.
| freetime2 wrote:
| Yup, after watching that video, I think I need to go out
| and practice that technique - hopefully it will become
| muscle memory in the event of a true emergency stop!
| donatj wrote:
| Came here to cite this video. It's wonderfully done. I think I
| knew it intrinsically but had never thought about it until this
| video came out.
| Lio wrote:
| Yes totally agree. One of the examples given of leaning a
| balanced broom is really intuitive.
| Asooka wrote:
| Sadly it's wrong. My gripe with it is that it presents
| countersteering as _necessary_ , while it's just a technique to
| more quickly initiate a turn.
|
| Basically by steering right while leaning left, then snapping
| the handlebars to the left, you can change your centre of
| gravity relative to the bike's faster than you can just by
| leaning left. When leaning your body left you also naturally
| push the handle bars right which produces a countersteer as
| well even if you didn't mean to.
|
| However, you can easily observe a bicycle steering without
| first initiating a countersteer. The easiest is if you just
| push it and let it coast by itself. It will naturally start
| leaning one way and continue turning that way until it falls on
| the ground without any countersteering. Another way is, if its
| geometry permits, to ride it without holding on to the
| handlebars - you can see you're steering left and right by
| shifting your weight on only the seat without any
| countersteering. Or you can consciously avoid doing a
| countersteer and make turns that way - noticeably less quickly
| than if you do countersteer, but quite possible.
|
| Another proof would be the fact that monowheels work and can be
| steered. You cannot countersteer a monowheel, yet it steers
| just fine. Look also at Destin's backwards bicycle experiment -
| https://www.youtube.com/watch?v=MFzDaBzBlL0 . I really don't
| think you can countersteer that thing anyway, yet it steers
| just fine.
|
| I think if Veritasium had given people more time (days? weeks?)
| to adjust to the bike, they would learn to make turns without
| countersteering. I know it took me a while to learn to do it
| when I first heard about countersteering and thought to
| experiment.
|
| Finally, I really hate the word "countersteering". It is very
| misleading and logically impossible. Obviously you can't have
| to turn left before turning right, because then you have to
| first turn right in order to turn left in order to turn right,
| but you have to first turn left in order to turn right in order
| to turn left in order to turn right... ad nauseam. A much
| better term would be "counterjerk" - you're jerking the bike to
| the right so that you can more quickly shift your centre of
| gravity left and make a sharper left turn.
| balfirevic wrote:
| > Look also at Destin's backwards bicycle experiment -
| https://www.youtube.com/watch?v=MFzDaBzBlL0 . I really don't
| think you can countersteer that thing anyway, yet it steers
| just fine.
|
| Why wouldn't you be able to countersteer it as any other bike
| (except in this case by using the opposite handlebar motion
| compared to a regular bike)?
| Uptrenda wrote:
| I'm now imagining some poor child's dumbfounded look as a
| HackerNews parent explains how to ride a bike by breaking down
| countersteering. lmaoo
| HPsquared wrote:
| "First, let's start with some control theory..."
| Lio wrote:
| Haha, you something like counter steering just being a monoid
| in the category of endofunctors? :P
|
| Hopefully after kids "just learn" how to ride, watching a video
| of someone counter steering in slow motion and then trying to
| visualise themselves doing it enough to get it.
|
| It is worth thinking about and then deliberately practicing
| though as nailing it can really help you reduce turning circle
| needed on both a motorbike and bicycle in general.
| kevstev wrote:
| I actually really struggled with this when taking a class
| learning to ride a motorcycle. The instructor kept trying to
| instill this over complicated explanation and mnemonics like
| "go left look left push left lean left" and IMHO it required
| way too much mental processing to just say "turn like a
| bicycle" Eventually after a few go rounds I realized he was
| just trying to explain that process and I just discarded all
| of the explanations and just did what came naturally (aside
| from the look part- that's actually immensely powerful and
| useful- just look where you want to go and avoid "target
| fixation").
|
| Some things, just doing them and getting a natural feel is
| 100x if not more, useful than tons of theory and
| explanations.
| ekzy wrote:
| From the Wikipedia article:
|
| > While this appears to be a complex sequence of motions, it is
| performed by every child who rides a bicycle. The entire
| sequence goes largely unnoticed by most riders, which is why
| some assert that they do not do it.
| Enginerrrd wrote:
| It's worse than that even... Historically, (before balance
| bikes) a lot of kids would progress from having training wheels
| all the way down, to two-wheeled dynamics. The problem is,
| having training wheels all-the-way-down means you have a
| tricycle, which doesn't have countersteering dynamics. So as
| soon as you pull the wheels up, they have to totally forget
| what they've learned.
| amalcon wrote:
| I don't think I've ever heard of training wheels at literal
| ground level when the bike is upright -- what would even be
| the point? It's basically a tricycle, like you say.
|
| When I've seen them, they've been at least an inch or two
| above, which (coupled with telling the child that the game is
| to prevent them touching the ground) would seem to mitigate
| this problem while still effectively preventing falls.
| synu wrote:
| Here in the Netherlands kids learn to ride a bike on little
| two wheeled wooden bikes, that they start to "glide" on. It's
| a nice system that gets them right into learning how a real
| bike behaves.
| gwd wrote:
| Those are the "balance bikes" GP are referring to;
| definitely a much better system than training wheels. (One
| of my 2-year-old's favorite activities ATM is riding his
| balance bike at a skate park.)
|
| I've heard people say that even when teaching adults to
| ride a bike, it's best to have them just push themselves by
| their feet (as you would on a balance bike) until they
| learn how the bike moves, then tell them to use the pedals
| whenever they feel ready.
| deltarholamda wrote:
| I did this for my kids, only I took the pedals off the
| bike so they could get full use of their legs. A balance
| bike without having to buy a separate bike.
| robust-cactus wrote:
| https://youtu.be/ZpV2Bg-WX0w
|
| This visual demonstration was helpful for me!
| moolcool wrote:
| The video says "by many bike riders"-- actually all! The only
| way to steer a motorcycle (or bicycle) at speed is to
| countersteer, even if you don't realize you're doing it
| frankdejonge wrote:
| In the Netherlands, countersteering is part of any motorbike
| practical exam. This is not standard in a lot of companies, but
| it is such an essential skill. It literally saves lives.
| draven wrote:
| In France we learn about it, and the exam has a low speed and
| high speed test. The high speed test ends with either an
| emergency stop or an obstacle avoidance (simulates a pedestrian
| crossing right in front of the motorbike for example, the
| maneuver requires countersteering.)
| mort96 wrote:
| I'm not sure what you mean by "it literally saves lives".
| Anyone who rides a single-track vehicle will instinctively do
| it any time they turn. Do you mean that having a more conscious
| relationship with how you countersteer when turning can help
| keep control in particularly difficult turns?
| kubanczyk wrote:
| When entering the turn - maybe.
|
| It's different when a novice is already progressing through a
| long turn and suddenly needs to tighten (obstacle or
| overshoot). They already feel less safe as soon as the bike
| is at an angle, and have instinctive tendency to begin
| straightening it up at even the slightest provocation. This
| instinct will 99% win with the undeveloped/unconscious
| countersteering instinct. (What? Point my handlebar _at the
| obstacle_?!) So, yes, training it could save their life.
| McNutty wrote:
| I really feel like when a motorcycle is travelling at greater
| than 30 40 or 50 kph, countersteering is the only way to
| steer. But doing it subconsciously and doing it with
| knowledge on the subject are 2 different feelings.
| Hamuko wrote:
| > _Anyone who rides a single-track vehicle will instinctively
| do it any time they turn._
|
| I've seen videos that suggest otherwise. Not linking it,
| since the last time I did, I got downvoted to hell and back
| for it.
| ehnto wrote:
| You can't turn a bicycle or motorbike without counter-
| steering, so these people are just not turning their bikes?
| It's not possible to not countersteer as the bike would
| lean to the wrong direction and you'd turn the wrong way
| (since you'd have been initiating a countersteer,
| afterall). Are you seeing people just manhandle the bars
| the wrong way in emergencies? I could believe that.
|
| https://www.youtube.com/watch?v=9cNmUNHSBac
| projektfu wrote:
| That's exactly it. Countersteering is a learned behavior
| that people aren't aware they do. They will describe it
| as leaning into the turn or whatever. Then, when they are
| in an emergency and need a tighter turning radius, they
| instinctively put in the wrong input and the bike
| straightens up. Explicitly teaching countersteering helps
| teach them to respond to emergencies with the correct
| input.
| engineer_22 wrote:
| I have been riding a bicycle all my life, so I suppose that I
| was counter steering unconsciously. I recently started riding
| a motorcycle and the experience is quite a bit different
| because it takes force and conscious effort to turn the bars
| on a machine weighing several hundred pounds. I think that
| people try to turn with their bodyweight instead of steering
| inputs if they don't know any better.
| yial wrote:
| I'm not sure what motorcycle you have, but when steering
| properly most I have owned have been effortless to turn
| when "pressing". (That being said I had a 1981 XS400 that
| someone had put some pretty silly bars on that felt like a
| jumping rock to turn)
| kubanczyk wrote:
| It's effortless on a motorbike. On a bike it's effortless
| squared, a near-undetectable planck-scale force on a
| handle, or just a body action.
| wildrhythms wrote:
| How does this happen? In the U.S. we have the Motorcycle Safety
| Foundation (MSF) which teaches a basic motorcycle riding
| course, and can give you a certificate for a motorcycle
| endorsement on your state license. One of their only
| prerequisites for the course is that you can ride a bicycle,
| because it guarantees the rider understands countersteering at
| low speeds before getting anywhere near a motorcycle.
| ehnto wrote:
| The MSF isn't mandatory though is it? Also, statistics
| suggest a lot of the motorcyclists who get killed are doing
| it without a license anyway (or registered bike, or
| helmet...).
| cdot2 wrote:
| It is for some states. I know here in Texas it is.
| pessimizer wrote:
| I don't think it is in Illinois, although the state sends
| people to MSF class "graduations" to do official tests.
| vceder wrote:
| In EU motorbikes fall under a different license then cars, so
| it involves both practical and theoretical test. What I know
| from the Swedish licenses is that the motorbike one is
| considered the more difficult test to pass.
|
| There is a "high speed" slalom course you have to do as part
| of the test and it's impossible to do it without counter
| steering through it.
| cdot2 wrote:
| Its impossible to steer a bike without countersteering. The
| speed is irrelevant.
| thefz wrote:
| In mountain biking where you turn more by leaning the bike and
| rotating the hips, it is very evident that briefly steering by
| rotating the handlebar to the opposite direction points the head
| tube of the frame right into the turn, and then it's just a
| matter of straightening the handlebar and leaning into the
| corner.
| ehnto wrote:
| I think the hips is mostly about the ergonomics of getting the
| right weight distribution for the bike, but the countersteering
| is the same. lean the bike over with the opposite steering
| input, and the whole situation leans over (including you!)
| thefz wrote:
| Turning the hips does a lot of subtle things, it impresses a
| rotational force to the rear wheel helping it to pivot on
| itself, and a rotational force into the pedals to further
| help the frame to rotate on itself. Further than that, it
| forces your head to turn into the direction you are heading
| and your shoulder line to stay parallel with the handlebar.
|
| Man, bike-human mechanics are complicated.
| Johnsorc wrote:
| From my days of racing downhill mtb and cycling this came
| naturally to me when I first got on a moto. I still have a really
| hard time describing the how, but can execute it intuitively.
| It's a really strange concept to wrap my head around.
| Ambolia wrote:
| Am I missing something on the top diagram of the article labeled
| "A hypothetical curve on dry asphalt"? It has sections labeled
| "counterstearing" but I don't see any counterstearing in the
| movement marked in red. While on the real-life images below it
| clearly shows it.
| ehnto wrote:
| In the bottom right of the image is the text "countersteer
| left", denoting the part of the turn where you might
| countersteer left in order to get the bike to turn right. You
| would not go perceptibly left according to the line, when you
| steer slightly to the left, the bike immediately leans over to
| the right and the front wheel steers right immediately also.
| The act of countersteering is entirely about leaning the bike
| over, the resulting turn to the right is actually a second
| order effect of that lean.
| rasz wrote:
| also https://en.wikipedia.org/wiki/Scandinavian_flick
| saagarjha wrote:
| KANSEI DORIFTO!!?!
| aaaaaaaaaaab wrote:
| N-nani??
| sph wrote:
| Here's an example of a beautifully executed Scandinavian flick:
| https://www.youtube.com/watch?v=0CQ-fsoGkd8 -- very common in
| rally driving.
|
| Often it's very well modelled in rally games as well, and
| crucial for making the best times:
| https://www.youtube.com/watch?v=OhfW1Vwgek0
| exDM69 wrote:
| The original article is about counter steering in bicycles and
| motorcycles to initiate a turn, not counter steering (or
| "opposite lock") in a car (or motorcycle/bicycle) in response
| to oversteer.
|
| That said, they're quite all quite interesting phenomena in
| vehicle dynamics.
| sph wrote:
| The flick is not about responding to oversteer. It's about
| using the physics of weight transfer to more easily negotiate
| a turn. On a rally car, the counterweight is the car itself,
| on a bike, it's the human.
| exDM69 wrote:
| I guess they have some superficial similarity but the
| vehicle dynamics are really different. In a scandi flick,
| the weight transfer is used to unload weight from the
| outside tyres to make them slip. In two wheel counter
| steering it's to initiate a balanced lean to the inside. In
| both cases, the driver turns the steering to the "wrong"
| direction.
| codingdave wrote:
| I have never grokked written or verbal explanations of
| countersteering. I have been riding bicycles and motorcycles for
| almost 5 decades now - I do it all the time in practice. But
| explaining it makes it weird.
| jeffbee wrote:
| I think an easy way to at least prove to yourself that it is
| happening is to ride a bicycle with just one finger of one hand
| in a straight line, then very slightly push the bar with that
| finger. Pushing to the right (ie with your left index finger)
| will initiate a left lean and turn. It's more obvious that way
| than with a normal grip.
|
| The simplest way to understand it is to consider that if the
| bike did not do this, it would be unrideable. The bike tends to
| return to center. If turning the wheel right initiated a right
| turn, the bike would just fall over.
| andrewsuzuki wrote:
| A normal stable turn requires a lean in the same direction. If
| you turn the bars to the left but don't lean to the left, you
| will topple over to the right.
|
| Countersteering is purposefully turning to the left and NOT
| leaning to the left, causing you to begin to topple over to the
| right...but then you quickly save it by turning the bars to the
| right. Now you are turning and leaning to the right.
| MarkMarine wrote:
| At speeds faster than parking lot speeds, that is incorrect.
| You purposely push the left bar away from you to turn left.
| That's all you do.
|
| https://www.youtube.com/watch?v=ljywO-B_yew
|
| Check it out.
| andrewsuzuki wrote:
| You're totally right. But I believe the explanation still
| basically holds, at the end instead it's the bike turning
| itself to save itself due to its inherent stability.
| mrnaught wrote:
| This! I think people from south east Asia can relate to this.
| I've been an active rider for over a decade before coming to
| US. When counter steering was taught in the motorcycle safety
| program,it felt counter intuitive. One reason I can think of is
| back in my home country max speeds were under 50mph where you
| dont have to counter steer that much.
| cdot2 wrote:
| You're countersteering at all speeds. It's just not as
| obvious.
| MarkMarine wrote:
| This is actually why this needed to be written, new riders on a
| race track come with a malformed understanding of how the bike
| works, and when you need to put more force into the bike to
| turn at higher speed, they don't know where to put the force.
| People think that just leaning does the work, but you can try
| to turn a motorcycle with your hands off the bar and see how
| that works... basically you just go straight.
|
| The part I find amazing is you understand how to make this work
| in a part of your brain that apparently doesn't communicate
| with the conscious understanding part. People can ride a
| motorcycle and not even understand how to make it turn, yet
| they do it.
| toast0 wrote:
| > The part I find amazing is you understand how to make this
| work in a part of your brain that apparently doesn't
| communicate with the conscious understanding part. People can
| ride a motorcycle and not even understand how to make it
| turn, yet they do it.
|
| Being able to do a thing is vastly different from being able
| to explain how to do a thing. If you ask me how I turn on a
| bike, the real answer is I just have the intention to go that
| way, and then I start going that way. Lots of other things
| are like that too; ask someone who is fast at word searches
| how they do it and it'll be something like "I kind of look at
| the grid and the word(s) pop out; and if it gets really tough
| I move my head around a bit and then they pop out" Not very
| helpful if that's not what happens to you, but it's what I
| do.
| intortus wrote:
| Torque clockwise to lean more toward the left. Torque counter-
| clockwise to lean more toward the right. The bike follows a
| radius proportional to its lean angle.
| amarant wrote:
| There's counter-steering, and then there's speedway
|
| https://en.m.wikipedia.org/wiki/Motorcycle_speedway
|
| Interesting physics indeed!
| mod wrote:
| https://www.youtube.com/watch?v=JWuTcJcqAng
| copperx wrote:
| Many people do this when driving a truck when turning 90 degrees
| to offset the small turn radius, but I have also seen people in
| cars do it, which is dangerous for the people in the next lane. I
| had always wondered where that behavior came from, but now I
| realize that they probably are motorcycle drivers.
| agurk wrote:
| I got a new (to me) motorcycle this year for a long trip I was
| planning and one of the things that surprised me was how much
| countersteer it needed to navigate tight mountain turns. I could
| definitely feel it in my arms at the end of each day.
|
| A few thousand kilometers into the trip I changed the front tyre
| as it had hit the wear bars and was amazed how completely it
| changed the handling of the bike. Instantly I stopped needing to
| consciously countersteer to enter turns and needed to shift my
| weight in the saddle a lot loss too.
|
| My assumption is that the new tyre has a cross-section that's a
| lot rounder than the old/worn tyres. I would have taken photos to
| compare them if I had realised that it would make such a
| difference. It was also a different brand (I didn't have much
| choice when I changed it) which also would have brought a
| different profile with it.
| pryelluw wrote:
| Nice, what bike?
| agurk wrote:
| A Yamaha XSR900 - probably not what people would think of as
| a natural bike to go on a 5500 km journey from Northern
| Europe to the Balkans, but you really can tour on anything.
| It was great in the alpine roads - especially the few days I
| did unloaded. It wasn't ideal on the few unpaved roads I
| found - especially with road tyres - but I coped with it. A
| few more litres in the tank (only 14L, ~300km) would have
| been helpful.
|
| Luggage was a bit harder due to limited options but I got a
| 48L tailpack and a 12L tank bag. With a few straps and
| bungees I had enough space to fit everything needed for
| riding and camping.
| pryelluw wrote:
| That's a nice bike. Enjoy!
| tbyehl wrote:
| A noticeable reduction in steering effort and weight shifting
| sounds like the new tire was inflated a few PSI higher than the
| old. Every motorcycle I've owned takes the corners MUCH easier
| with 2-3 more PSI in front than the manual states.
| harvie wrote:
| What happens when you don't understand countersteering:
| https://youtu.be/VVE79XT8-Mg
| HPsquared wrote:
| It helps to think of the bicycle/motorcycle as an inverted
| pendulum. To sustain an acceleration in a given (lateral)
| direction, it must lean in that direction.
|
| Countersteering helps to control/initiate the lean angle. To lean
| to the right, the rider steers to the left and the wheels (at the
| bottom) move to the left while the centre of mass stays where it
| was initially, thus the angle begins to lean to the right,
| initiating a steady rightwards acceleration.
| CraigJPerry wrote:
| There's a lot about riding a motorbike that feels
| counterintuitive. The way this article is written it sounds like
| you can only initiate the steer with a counter steer but even if
| you're already in a bend you can provide a counter input to
| tighten your line and steer harder. It's taught pretty early on
| for new riders and it saves lives.
|
| There's loads of other weird things, because the rear tire is
| wider than the front, the contact patch is bigger at the rear, so
| to extract maximum grip you need a rearward weight transfer, so
| lightly accelerating in a turn is optimal. Even when not pursuing
| max grip you'd still do this to keep the envelope large around
| your actual grip requirements.
|
| Although The front wheel has a smaller contact patch, the contact
| patch at the front is often a different shape- the front wheel is
| often a larger diameter so it has a longer but narrower contact
| patch than the rear. That makes for a vehicle that tracks and
| responds differently over uneven ground at the front vs the back
| which leads to you needing to let the front move itself, a
| relaxed grip is needed on the bars over uneven surfaces,
| otherwise you will transfer so of that motion from the
| handlebars, through your body to the pegs and the seat. That will
| lead to a loss of control. Utterly counter intuitive that to
| retain control over rough ground you want to almost let go of the
| handlebars.
|
| There's two great books - for direct machine control, "a twist of
| the wrist" volume 2 by keith code and for more abstract how to
| think about machine control - not So much how to steer but why to
| steer and where to - then roadcraft by the uk police is another
| great book.
| koonsolo wrote:
| Motorcycle physics are very interesting to say the least. My
| favorite is this:
|
| What happens to the suspensions when you brake? Front one
| compresses while the back one extends. That one was easy. Now
| this:
|
| What happens to the suspensions when you accelerate? Front one
| extends while the back one... also extends.
|
| Motorcycles are specially designed to have this last behavior.
| ahartmetz wrote:
| Something I've only read about... Earlier BMW motorcycles
| with shaft drive were infamous for their "Gummikuh" ("rubber
| cow") behavior, rising strongly in the rear when
| accelerating. The shaft drive was later modified to reduce
| that.
| sbaiddn wrote:
| Let me blow your mind:
|
| "What happens to the suspensions when you brake"
|
| Depends on the suspension!!
|
| Earles _front_ suspensions _rise_ on braking, transferring
| weight to the rear. Its counter intuitive until you realize
| that the forward momentum of the bike is on an arm that has
| to rise to allow forward motion of the body relative to the
| front tire.
|
| I think BMWs paralever could also rise on braking, but could
| be adjusted not to and all were.
| RileyJames wrote:
| A twist of the wrist. Great to see it show up here. The only
| instruction I took before I bought a bike and rode 6000km to
| the uyuni salt flats. With near zero experience, that film
| pretty much saved my life.
| interstice wrote:
| It's even more complex than that - motorcycle tyres have
| different curvature at the front and the rear, it's pretty hard
| to get to the edge at the front even with moderate braking but
| I have routinely run to or off the edge of various rears on
| track days.
|
| There's also fun things like the bikes geometry gets longer or
| shorter under acceleration or braking to help with turning and
| grip. The physics is quite beautiful (and a lot of fun)
| MarkMarine wrote:
| Using the whole front is there for some pretty extreme trail
| braking, more than I put into the front that's for sure. I do
| have a comfortable 1-2 day use period for a rear on my R6,
| while I kind of squint at the front and figure I better
| replace it every couple rears I almost never feel it getting
| used up.
|
| Do you live in the Bay Area? What org do you ride with? I'm
| with PTT for track days and AFM for racing.
| McNutty wrote:
| Twist 2 is available for free on YouTube. Filmed decades ago
| but motorcycles are still mostly the same.
| HPsquared wrote:
| On the second point (the need to maintain light acceleration)
| I'd always thought this was more to counteract engine braking -
| if there is engine braking, that is more demand on the rear
| tyre, kind of like applying the brake - which takes up a bit of
| the "available" friction that could be used for cornering.
| projektfu wrote:
| I would say it's more to keep some weight on the rear wheel
| and prevent a low-side crash. When the bike is slowing down
| the weight shifts to the front, whether through friction
| braking or engine braking. If you are already at the correct
| speed, lightly accelerating helps bring you through the
| corner with more even weight on the wheels. Incidentally,
| race car drivers do the same thing, except when drifting, but
| you almost never see intentional drifting in road racing.
| pessimizer wrote:
| I always thought that it's simply because as you turn
| left/right, the bike will fall to the left/right, and the
| acceleration delivers an outward force that levers the bike
| up against the friction of its tires (and disappears once the
| bike is vertical) i.e. the same thing that keeps bikes
| vertical and straight by themselves as long as they're
| getting power. That being said, I'm a rider not a thinker.
| Phenomenit wrote:
| I think its for overcoming the braking that occurs when you
| turn because of the normal force. Even if you hold down the
| clutch the bike will brake more that if you run in a straight
| line.
| ehnto wrote:
| I can only really explain it intuitively, in that when you
| pull on the rear brake or engine brake, the angular forces of
| the rotation of the wheel are transferred into making your
| bike straighten up vertically. I don't know if that actually
| happens, but that's how it feels.
|
| Part of it is also similar to the reasons you trail brake
| into corners, in that you're managing the weight distribution
| over your tires. You don't want to be erratically changing
| how much weight is on the front tires, otherwise you'll find
| you suddenly have a lot less front grip.
| KennyBlanken wrote:
| I can't speak to motorcycles, but when driving a car at the
| track there's "maintenance throttle" which is partly to
| counter the slowing you get from the tires scrubbing, and
| partly to balance 'weight'; most cars are far heavier up
| front than in back, so a bit of throttle puts a bit more
| weight on the back of the car, which helps keep the front
| outside tire from getting overloaded but also puts some
| weight on the back tires for more grip. It also offers the
| option to induce some oversteer via throttle lift, if
| necessary.
| CraigJPerry wrote:
| That's right, in a car as you go into a corner you first
| steer a little bit, the car then "takes a set" - i have no
| idea where that terminology comes from but it just means
| the car moves to a steady state of loading up the outside
| suspension. Once you feel the car has taken a set, you can
| crank on a lot more steering. I'm describing it as two
| phases but the best drivers smooth both of these phases
| into one flowing motion - slowly steer at first then steer
| faster. Doing it in this two phase approach allows for far
| higher lateral g to be built in the turn than if you just
| smoothly turn at the same rate. You extract more grip
| because you build weight over the tire before asking it to
| grip and grip is parlty a function of weight on the tyre.
|
| In most car drivetrain configurations you'd then use a
| balanced throttle through the turn.
|
| You can use a balanced throttle on a bike too - many people
| do - but all race bikes and most advanced riders even in
| non race scenarios will use a slight acceleration not a
| balanced throttle because where in the car you want to
| settle the suspension with a heavy loading equally on your
| two outside wheels (e.g. in an FR layout car) on a bike you
| want to have around 65% weight on the rear.
|
| There's a similar effect with the Porsche 911 - it's an RR
| layout with 12 inch wide tyres at the rear and a slight
| acceleration is optimimum for it.
| panxyh wrote:
| Counteracting engine braking happens already at maintaining
| speed. Maintaining acceleration is maintaining _acceleration_
| , with the obvious effect of moving more weight on the back
| wheel and shortening the bike.
| mod wrote:
| Big second recommendation for twist of the wrist. You can watch
| a pretty cheesy, but very informative version of it on youtube.
|
| Craig, thanks for the comment and recommendations. I think I'll
| check out Roadcraft.
| randlet wrote:
| "Pretty cheesy" might be a bit of an understatement but it's
| a good companion to the TOTW2 book.
| mod wrote:
| The acting scenes are incredibly cheesy, and the rest of it
| is fine, just with a bit of a retro vibe. Dude's facial
| hair etc.
| vr46 wrote:
| +100 for Twist of the Wrist Volume 2
|
| Although I think Roadcraft has been "superseded" by IAM with a
| simplified version called "How to be a better driver", I would
| use both.
| sushiburps wrote:
| It's fascinating that the explanation of a countersteer is
| counterintuitive, but most people pick up on it without being
| taught. Kids learning to ride a bicycle will naturally add the
| countersteer before a turn.
| wanderingmoose wrote:
| Keith Code (author of twist of the wrist) has a bike with fixed
| handle bars that he lets you ride as part of his superbike
| track/race school. It is really eye opening on how little
| control you have without countersteering.
|
| Here's a vid: https://www.youtube.com/watch?v=8VqXBA-sGHA
|
| His school: https://superbikeschool.com/
| d1l wrote:
| Twist of the wrist is fantastic, as is the video, which can be
| found on YouTube. Agree with everything you said, and I'm
| curious: what do you ride? I've been tracking a mostly-stock R6
| for the last 5 years, A the last 3 or 4. One thing I thought
| I'd add is that with motorcycles, the rider is a significant
| fraction of the total mass, so your position on the bike can
| greatly affect the center of gravity. You see guys leaning off
| the bike (towards the apex of a corner), which allows the bike
| to stand up taller, thus requiring less lean angle/more contact
| patch, which allows for higher speed and better grip at corner
| exit.
|
| Oh and another surprising thing: on track I never use the rear
| brake when braking hard. Why? Hard braking lifts the rear
| wheel, and when you use the rear brake it becomes incredibly
| easy to lose rear traction!
| CraigJPerry wrote:
| >> what do you ride
|
| I sold my S1000XR (first generation) and was all set for a
| Tuono V4 but i really didn't get on with it. I'm 6'3 so a 2nd
| gen S1000XR looks likely next. I'd love a shot on the new
| Triumph TE-1 when it launches though.
|
| >> I've been tracking a mostly-stock R6
|
| I think that's the most popular bike here too, if i had space
| for 2 bikes, i'd do the same as you and have an R6 for track.
| d1l wrote:
| Nice, I see some rsv4's at the track, still waiting to see
| a new rs660 so I can bombard the owner with questions. The
| new R7 is supposed to be "fun" to track, as it's got the
| more user-friendly mt07 engine, but its nothing compared to
| the scream of the 6. When mine inevitably blows up I'll
| probably be looking between the aprilia or maybe a gsxrr.
| saraton1n wrote:
| yea, it's so much easier to lock the rear tire when braking
| hard. i've owned two different Suzuki GS500s (a 1996 GS500e
| and a 2006 GS500f) and both of them were notoriously easy to
| lock up the rear wheel on
| dj_mc_merlin wrote:
| > Utterly counter intuitive that to retain control over rough
| ground you want to almost let go of the handlebars.
|
| I've hiked through a lot of forests ever since I was a kid and
| have a method, often criticized, but that has never injured me,
| of going down difficult terrain. I more or less glide down at a
| constant speed, putting my feet in places to apply upwards
| force. It helps a great deal that I have very flexible angles
| and can bend at near 90 degree angles. I usually get down very
| quickly and without fuss, whereas the slower more deliberate
| method tends to produce bigger falls. You tense up more when
| you're going down like that, and are more likely to produce
| uncontrolled fall, which is what kills you. If you can control
| your fall (throw yourself lightly at a patch that will stop you
| quickly and not injure you) and go a bit limp to disperse
| energy quickly, you can fall a lot more than most people but
| get injured less. I learned this technique from skateboarding.
| The idea is to learn to do a controlled fall whenever you're in
| danger into a safe area, rather than possibly risk an
| uncontrolled fall.
|
| I've been called an idiot for doing this but I have never
| broken a bone nor had significant injury while hiking.
|
| Anyway, my point is, sometimes just letting the movement flow
| naturally is the correct thing to do, even if it means the
| speed involved/perceived danger is higher.
| tnelsond2 wrote:
| Not sure I follow. What I do is let gravity push me downhill
| and I keep one foot in front of the other and I gallop,
| hopping down the hill but always keeping a leading foot so
| that I never have to do the full movement of switching legs
| like in normal walking.
|
| Because I don't switch my feet I can keep up faster than I
| can run and I don't slip because I always have 2 feet on the
| ground at a time and it's kinda like surfing without the
| board.
| Gravityloss wrote:
| That's also how you move down on slippery icy slopes.
| js2 wrote:
| Kilian Jornet running downhill:
|
| https://www.youtube.com/watch?v=UBxvn9yEdlY
|
| https://www.youtube.com/watch?v=A7agNyuN39E
| tnelsond2 wrote:
| My technique for running downhill. Not sure why nobody else
| uses it.
|
| I gallop like a deer and I can go incredibly fast by
| basically keeping one foot constantly in front and never
| switching it and hopping down hills. I don't have to take a
| full step and I always have two feet or no feet on the
| ground so it's impossible to slip.
|
| https://youtu.be/lHcZo5mrv2k
| benj111 wrote:
| Living in a hilly area, this is the way to go down hills. If
| you tense you get tired going down, aswell as up hills.
| potamic wrote:
| Sounds interesting, but I'm unable to picture what you're
| saying. Are there any videos I can watch about this
| technique?
| white_dragon88 wrote:
| No video will show the subtle differences. The principle is
| that you would let the physical aspects of the ride flow
| through your bike to minimise shock and allow the bike to
| more naturally 'fall' through the path that will take it
| the easiest.
|
| An good analogue would be jet skiing. If you just hold on
| for dear life and hope for the best, you will get a very
| sore back. A lot about doing it right is letting the waves
| do what they have to do, and making subtle corrections to
| ensure your path is optimal but taking into account the
| obstacles it's encountering
| potamic wrote:
| Are they talking about hiking or biking?
| benj111 wrote:
| Walking is basically controlled falling. This is basically
| an extension of that. You just let one leg go in front of
| the other like you were walking, rather than taking
| singular steps.
| abalaji wrote:
| There is a surprising lack of pixar Cars references in this
| thread... it's where I was first exposed to counter-steering
|
| https://www.youtube.com/watch?v=zUWtaw5Fra8
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