How can I corner faster?

toadontheroad

I am rubbish at cornering at speed, i get really nervous and brake far too much for all but the slightest kink. I'm not sure if its confidence in the tyres (conti sport ultras - 23) or something else (probably fear of falling lol!) but its very annoying more than anything else. I try to get the pedals in hte right position so the opposite pedal to the way i turn is down, i try to push my knee out a bit, i try to keep my weight central but all hte time i just end up braking and riding like a big girls blouse.

do i just need to pile it in and hope for the best?, Should I ride the same conrner faster and faster till i find where the tipping point is and actually crash? should i take up darts instead?

andrewgturnbull

Here are the tips from the legends that are Jobst Barndt and Sheldon Brown:
see http://www.sheldonbrown.com/brandt/descending.html

Descending and Fast Cornering
Descending on mountain roads, bicycles can reach speeds that are more common on motorcycles. Speeds that are otherwise not attainable, or at least not continuously. Criterium racing also presents this challenge, but not as intensely. Unlike a motorcycle, the bicycle is lighter than the rider and power cannot be applied when banked over when cornering hard. Because narrow bicycle tires inflated hard have little traction margin, a slip on pavement is usually unrecoverable.
Drifting a Road Bicycle on Pavement
Riders have claimed they can slide a bicycle on dry pavement in curves to achieve greater cornering speed, as in drifting through a turn. A drift, in contrast to a slide, means that both wheels slip, which is even more difficult. This notion may come from observing motorcycles, that can cause a rear wheel slide by applying power when banked over. Besides, when questioned about how this is done, the proponent says that the ability was observed, done by others.
A bicycle can be pedaled only at lean angles far less than the maximum without grounding a pedal, so hard cornering is always done coasting, hence, there is no power in hard cornering. Although bicycles with high ground clearance have been built, they showed only that pedaling imbalance has such a disturbing influence on traction, that pedaling at a greater lean angle than that of a standard road racing bicycles has no benefit. That is why road bicycles are built the way they are, no higher than is useful.

That bicycle tires have no margin for recovering a slip at maximum lean angle, has been tested in lean-slip tests on roads and testing machines. For smooth tires on pavement, slipout occurs at slightly less than 45 degrees from the road surface and is both precipitous and unrecoverable. Although knobby tires have a less sudden slipout and can be drifted around curves, they begin to side-slip at a more upright angle as their tread fingers walk rather than slip. For this reason, knobby tires cannot achieve lean angles of smooth tires and offer no cornering advantage on pavement.

How to Corner
Cornering requires estimating the required lean angle before reaching the apex of the turn where the angle with the road surface is the critical parameter rather the angle with the vertical, as is evident from banked curves. Lean angle is limited by the available traction that must be assessed from velocity and appearance of the surface. For good pavement, this angle is about 45 degrees, in the absence of oil, water, or smooth and slick spots. Therefore, a curve banked inward 10 degrees, allows a lean of up to at least 55 degrees from the vertical, while a crowned road with no banking, where the surface falls off about 10 degrees, would allow only up to 35 degrees.
Banked curves have a greater effect than just adding to the maximum lean angle, because with a steeper banking, more of the centripetal cornering force goes into increasing traction directly into the banking up to the point of a vertical wall where only the maximum G-forces limit what speed a bicyclists can attain. In contrast, an off banked curve makes cornering progressively more difficult until the bicycle will slip even at zero speed. This effect is more naturally apparent to riders who exceeded these limits early in life and have added the experience to expected natural phenomena.

The skill of visualizing effects of speed, traction, braking, and curvature are complex, but is something humans and other creatures do regularly in self propulsion. The difficulty arises in adapting this to higher speeds. When running, we anticipate how fast and sharply to turn on a sidewalk, dirt track, or lawn, to avoid sliding. The method is the same on a bicycle although the consequences of error are more severe.

Cornering requires reflexes to dynamics that are easily developed in youth, while people who have not exercised this in a long time find they can no longer summon these skills. A single fall strongly reinforces doubt, so cautious practice is advisable if returning to bicycling after a long time.

Countersteer
Countersteer is a popular subject for people who belatedly discover or rediscover how to balance. What is not apparent, is that two wheeled vehicles can be controlled ONLY by countersteer, there is no other way. Unlike a car, a bicycle cannot be diverted from a straight path by steering the wheel to one side. The bicycle must first be leaned in that direction by steering it ever so slightly the other way. This is the means by which a broomstick is balanced on the palm of the hand or a bicycle on the road. The point of support is moved beneath the mass, in line with the combined forces of gravity and cornering, and it requires steering, counter and otherwise. It is so obvious that runners never mention it, although football, basketball, and ice hockey players conspicuously do it.
Braking
Once the basics of getting around a corner are developed, doing it fast involves careful use of the brakes. Besides knowing how steeply to lean in curves, understanding braking makes the difference between the average and the fast rider. When approaching a curve with good traction, the front brake can be used almost exclusively, because it is capable of slowing the bicycle so rapidly that nearly all weight transfers to the front wheel, at which point the rear brake is nearly useless. Once in the curve, more and more traction is used to resist lateral slip as the lean angle increases, but that does not mean the brakes cannot be used. When banked over, braking should be done with both brakes, because now neither wheel has much traction to spare and with lighter braking, weight transfers diminishes. A feel for how hard the front brake must be applied for rear wheel lift-off, can be developed at low speed.
Braking in Corners
Why brake in the turn? If all braking is done before the turn, speed will be slower than necessary before the apex. Anticipating maximum speed for the apex is difficult, and because the path is not a circular arc, speed must be trimmed all the way to that point. Fear of braking in curves usually comes from an incident of injudicious braking at a point where braking should have been done with a gentle touch to match the conditions.
Substantial weight transfer from the rear to the front wheel will occur with strong use of the front brake on good traction just before entering the curve. When traction is poor or the lean angle is great, deceleration cannot be large and therefore, weight transfer will be small, so light braking with both wheels is appropriate. If traction is miserable, only the rear brake should be used, because although a rear skid is recoverable, a front skid is generally not. An exception to this is in deep snow, where the front wheel can slide and function as a sled runner while being steered.

Braking at maximum lean
For braking in a curve, take the example of a rider cornering with good traction, leaning at 45 degrees, the equivalent of 1G centrifugal acceleration. Braking with 1/10g increases the traction demand by one half percent. The sum of cornering and braking vectors is the square root of the sum of their squares, SQRT(1^2+0.1^2)=1.005 or an increase of 0.005. In other words, there is room to brake substantially during maximum cornering. Because the lean angle changes as the square of the speed, braking can rapidly reduce the angle and allow even more braking. For this reason skilled racers nearly always apply both brakes into the apex of turns.
Suspension
Beyond leaning and braking, suspension helps substantially in descending. For bicycles without built-in suspension, this is furnished by the legs. Standing up is not necessary on roads with fine ripples, just taking the weight off the pelvic bones is adequate. For rougher roads, enough clearance must be used so the saddle carries no weight. The reason for this is twofold. Vision will become blurred if the saddle is not unloaded, and traction will be compromised if the tires are not bearing with uniform force on the road while rolling over bumps. Ideally the tires should bear on the road at constant load. Besides, if the road has whoop-de-doos, the seated rider will get launched from the saddle and possibly crash.
Lean the Bicycle, the Rider, or Both
Some riders believe that sticking the knee out or leaning the body away from the bicycle, improves cornering. Sticking out a knee is the same thing that riders without cleats do when they stick out a foot in dirt track motorcycle fashion. On paved roads this is a useless but reassuring gesture that, on uneven roads, even degrades control. Any body weight that is not centered over the bicycle (leaning the bike or sticking out a knee) puts a side load on the bicycle, and side loads cause steering motions over uneven road. Getting weight off the saddle is also made more difficult by such maneuvers.
To verify this, coast down a straight but rough road, weight on one pedal with the bike slanted, and note how the bike follows an erratic line. In contrast, if you ride centered on the bike you can ride no-hands perfectly straight over the same road. While leaning off the bike, trail of the front wheel causes steering on rough roads.

Outside Pedal Down
It is often said that putting the outside pedal down in a curve improves cornering. Although most experienced riders do this, it is not because it has anything to do with traction. The reason is that it enables the rider to unload the saddle while standing with little effort on a locked knee, cushioning his weight on his ankle. This can only be done on the outside pedal because the inside pedal would hit the road. However, standing on one extended leg does not work on rougher roads, because the ankle cannot absorb large road bumps nor raise the rider high enough from the saddle to avoid getting bounced. Rough roads require rising high enough from the saddle to avoid hard contact while the legs supply shock absorbing knee action, with pedals and cranks horizontal.
Body Contortions
Most of the "body English" riders display is gratuitous gesturing, much like the motorcyclists who stick their butt out in curves while their bikes never get down to 45 degrees (the angle below which hiking out becomes necessary to keep hardware from dragging on the road). In fact, in a series of tight ess bends, there's no time to do any of this. It's done by supporting weight on the (horizontally positioned) pedals, and unless the road is rough, with a light load on the saddle. On rough roads, the cheeks of the saddle, (the ones that went away with the Flite like saddles) are used to hold the bicycle stably between the legs while not sitting.
The path through a curve is not symmetrical for a bicycle, because it can slow down much faster than it can regain speed. Thus the trajectory is naturally asymmetric. Brakes are generally used to the apex (that is usually not the middle) of the curve, where pedaling at that lean angle is not possible, nor does pedaling accelerate as fast as braking decelerates.

Hairpin Turns
Although the railroad term switchback arises from early mountain railroading where at the end of a traverse, a switch is turned to back up the next traverse, after which another switch is turned to head up the next, on roads these are hairpin turns. In such turns trajectory asymmetry is most conspicuous, because braking can be hard enough to raise the rear wheel when entering but one cannot exit with such acceleration. For this reason, riders often find themselves with extra road on the exit of such turns, having slowed down too much.
Vision
Where to direct vision is critical for fast cornering. Central vision should be focused on the pavement where the tire will track, while allowing peripheral vision, with its low resolution and good sensitivity to motion, to detect obstacles and possible oncoming traffic. Peripheral vision monitors surroundings anyway, so the presence of a car in that "backdrop" does not require additional consideration other than its path.
If central vision is directed at the place where an oncoming vehicle might appear, its appearance presents a new problem of confrontation, stopping image processing of the road surface for substantial time. Because the color or model of car is irrelevant, this job can be left to peripheral vision in high speed primitive processing, while concentrating on pavement surface and composition.

When following another bicycle or a car downhill, the same technique is even more important, because by focusing on the leading vehicle, pavement and road alignment information is being obscured giving a tendency to mentally become a passenger of that vehicle. Always look ahead of the vehicle, observing it only peripherally.

Riders often prefer to keep their head upright in curves, although leaning the head with the bicycle and body is more natural to the motion. Pilots who roll their aircraft do not attempt to keep their head level during the maneuver, or in curves, for that matter.


The Line
Picking the broadest curve through a corner may be obvious by the time the preceding skills are mastered, but that may not be the best line, either for safety or because the road surface is poor. Sometimes hitting a bump or a "Bott's dot" is better than altering the line, especially at high speed. Tires should be large enough to absorb the entire height of a lane marker without pinching the tube. This means that a minimum of a 25 mm actual cross section tire is advisable. At times, the crown of the road is sufficient to make broadening the curve, by taking the curve wide, counterproductive because the crown on the far side gives a restricted lean angle.

Mental Speed
Mental speed is demanded by all of these. However, being quick does not guarantee success, because judgment is even more important. To not be daring but rather to ride with a margin that leaves a feeling of comfort rather than high risk, is more important. Just the same, do not be blinded by the age old presumption that everyone who rides faster than I is crazy. "He descends like a madman!" is one of the most common descriptions of fast descenders. The comment generally means that the speaker is slower.
Braking Heat on Steep Descents
Although tandems with their higher weight to wind drag ratio have this problem more often, steep mountain roads, especially ones with poor or no pavement require so much braking that single bicycles blow off tires from overheating. For tubulars the problem is not so much over pressure than rim glue melting as all pressure sensitive glues do with heating. As glue softens, tires slip on the hot rim and pile up on the valve stem. This is the usual indicator that tubular tire wheels are too hot. The next is that the tire arches off the rim in the area just before the stem.
This is a serious problem both for tubulars and clinchers because most clincher tires, given enough time on a hot rim will blow off if inflated to recommended pressure. Pressure that gives good rolling performance (hard) while tubulars roll off from lack of adhesion to the rim. The faster the travel, the more descending power goes into wind drag and the better the rims are cooled. Going slowly does not help, unless speed is reduced below walking pace.

On steep descents, where rims stay too hot to touch for more than a minute, reducing tire inflation pressure is a sure remedy. However, tires should be re-inflated once the rims cool to normal. The blow-off pressure is the same for small and large tires on the same rim, it being dependent only on the opening of the rim width. Also, tires with a smaller air volume become hot faster than larger ones.

There is no way of descending continuously and steeply without reducing inflation pressure, unless there is an insulator between the tube and rim of a clincher. Insulating rim strips are no longer offered because they were an artifact of dirt roads that often required riders to descend so slowly that all potential energy went into the brakes and almost none into wind drag. These rim strips were cloth tubes filled with kapok, their insulating purpose being unknown to most people when they were last offered.


Cheers, Andy

Pokerface

:shock: :shock: :shock: :shock:

disgruntledgoat

This is something i've worked hard on over the years as my fast cornering (in a bunch) and my descending was atrocious... It's something you have to do for yourself as if you lack confidence in your equipment or your ability no amount of somebody telling you that it'll be fine is going to make you do it.

The best tips I've had over the years are

1) Lean the bike not your body, try and keep yourself in as neutral a position as possible with your head looking at where you want to go at all times.

2) Put your weight through the outside pedal to push the tyres into the road. THis should come as a function of 1) but I find making a concious effort to push down on the outside pedal makes a difference in my head.

3) Road tyres are a lot more stable and "glued down" than you think. You can get away with much more on a tarmac surface than you can off-road. All the MTBers I know told me that constantly.

4) Scrub your speed before you turn into a corner. Your brakes are trying to pull the bike in a straight line which is never going to help you once you've turned in. Even if you start off scrubbing way too much speed before you turn in and go through slowly, you'll be building confidence in your ablility to lean through a corner without correcting your line and braking.

5) Hold your line all the way through.

Hope those are of some help!

Ollieda

Countersteer............

I must have read that bit 5 times and I still don't quite understand.

Is it really saying that if I want to turn left I must first turn right slightly (or vice versa) surely this is not correct? Otherwise I just must be cycling wrong, I'm pretty sure that if I want to turn left I either turn the bars left or lean left.

bompington

Thanks andrewgt. I'll print that out on a card and attach it to my handlebars for a handy quick reference next time I'm heading down Jock's Brae towards the corner at 40+mph

robrauy

Thanks Disgruntledgoat - Useful advice.

I've just been out on the race bike to do some chores and found myself swooping round and round mini roundabouts as fast as possible to test your theories

The advice about keeping your weight on the outside pedal seemed to work well. I also feel more confident cornering on the drops - Not sure why though.

Looking forward to putting this all into practice at tomorrow's fun and games...

Bronzie

Ollieda wrote:

Countersteer............

I must have read that bit 5 times and I still don't quite understand.

Is it really saying that if I want to turn left I must first turn right slightly (or vice versa) surely this is not correct? Otherwise I just must be cycling wrong, I'm pretty sure that if I want to turn left I either turn the bars left or lean left.

It does work - a quick flick on the bars in the direction *opposite* of that you want to turn causes the bike to lean in the other direction (ie the direction you want to go) - has to be a quick movement though rather than "steering"

graeme_s-2

I wouldn't worry about the countersteering bit. Everyone on here is already doing it automatically, otherwise they'd be unable to corner at more than a very low speed. If you pay attention as you go from a straight line to leaning for a left hand bend you'll realise you give the bike a gentle nudge to the right a fraction of a second before you lean.

It's the main reason kids have so much trouble moving from stabilisers to a bike without. With stabilisers you steer by turning the handlebars in the direction you want to go, like you steer in a car. Once you take the stabilisers away you have to steer by leaning, and to do that you have to countersteer.

huuregeil

Two other points that haven't been mentioned.

1. You can "know" everything about cornering, but it won't make an ounce of difference until you "feel" it on the bike. Yup, this means practice makes perfect, and I think you just need to get out there, find a few safe bends and practice increasing your speed slowly but surely. And, of course, deploy the tricks mentioned here, weight on the outside pedal, look where you want to go, lean with the body. You do need to explore the limits a little, but do so in a safe, progressive and consistant manner.

2. Actually, my cornering didn't really improve until I started riding fixed gear. Two reasons: on braking for a bend, you can feel the amount of traction off the back wheel (e.g. brake with the front and you will spin the rear wheel if you're approaching its traction limit) and this gives you good feedback in slippy conditions; given decent tyres and decent road conditions, you'll pedal strike before losing grip, and a pedal strike is more recoverable than loss of grip. I've lost it on bends from losing grip before, but I've never lost it from pedal strike. You thus get a very good sense of a conservative lean angle, which is far greater than you might think.

ride_whenever

disgruntledgoat wrote:

Your brakes are trying to pull the bike in a straight line which is never going to help you once you've turned in.

Not strictly true, the rear pulls you into a straight line, the front tends to cause you to turn more as braking tends to make the front wheel want to tuck under.

ride_whenever

Borrow a mountainbike and practise off-road. You very quickly learn the limits of traction etc. and tumbles tend to be less severe.

It then transfers very easily onto the road.

Also look for the slightest slope you can use to push you round the corner.

chrisw12

ride_whenever wrote:

Borrow a mountainbike and practise off-road. You very quickly learn the limits of traction etc. and tumbles tend to be less severe.

It then transfers very easily onto the road.

Also look for the slightest slope you can use to push you round the corner.

Borrow a motorbike and practise on-road. You very quickly learn the limits of traction etc but tumbles tend to be more severe though.

Confidence transfers easily onto the cycle.

chrisw12

Two things I'm trying/thinking about at the moment when descending.

Why lean the bike and NOT lean the body. Surely if you you keep the bike as upright as possible then there's no chance of loosing traction?

On hairpins, I've been un-clipping the inside foot and sticking it out. It's allowing me to use a much tighter line as it quickens up the steering. Has anyone else tried this?

I've noticed the great Rossi doing this when he's pushing it but haven't seen anyone else.

I am in no way comparing myself to the God that is Valentino Rossi by the way, it's just a fun thing to try.

neil²

Ollieda wrote:

Countersteer............

I must have read that bit 5 times and I still don't quite understand.

Is it really saying that if I want to turn left I must first turn right slightly (or vice versa) surely this is not correct? Otherwise I just must be cycling wrong, I'm pretty sure that if I want to turn left I either turn the bars left or lean left.

countersteer explains why it is so difficult to steer out of a gutter if you get boxed in.

crumbschief

bompington wrote:

Thanks andrewgt. I'll print that out on a card and attach it to my handlebars for a handy quick reference next time I'm heading down Jock's Brae towards the corner at 40+mph

Lol,now let me see,apply foot toooo Ceeeeerunch.

Chrissz

Countersteering has it's uses - it puts the bike in the right position rather than having to move the body (a much heavier object).

Imagine looking at a rider from directly above, as he leans through a corner his body is on the inside and the bike is on the outside, drawing a slightly greater arc than the body. If you countersteer you put the bike 'out' much quicker than if you just lean and try to get the whole body 'in' - make sense?

Next week - the Scandinavian flick

oldwelshman

Its not always easy to put into words, may be easier to go on a group ride with experienced riders and follow them, it will become quite natural.

Pokerface

chrisw12 wrote:

Two things I'm trying/thinking about at the moment when descending.

Why lean the bike and NOT lean the body. Surely if you you keep the bike as upright as possible then there's no chance of loosing traction?

On hairpins, I've been un-clipping the inside foot and sticking it out. It's allowing me to use a much tighter line as it quickens up the steering. Has anyone else tried this?

I've noticed the great Rossi doing this when he's pushing it but haven't seen anyone else.

I am in no way comparing myself to the God that is Valentino Rossi by the way, it's just a fun thing to try.

Unclipping and putting your leg out!? WTF?

gbs

Bronzie wrote:

Ollieda wrote:

Countersteer............

I must have read that bit 5 times and I still don't quite understand.

Is it really saying that if I want to turn left I must first turn right slightly (or vice versa) surely this is not correct? Otherwise I just must be cycling wrong, I'm pretty sure that if I want to turn left I either turn the bars left or lean left.

It does work - a quick flick on the bars in the direction *opposite* of that you want to turn causes the bike to lean in the other direction (ie the direction you want to go) - has to be a quick movement though rather than "steering"

At last, an explanation of how to generate countersteer. Thankyou and if I survive I will post a critque.

rick_chasey

I found that pressing hard on the outside pedal during the turn made a MASSIVE difference.

Turned me from a Denis Menchov type to Sam Sanchez - made all the difference for me.

toadontheroad

guys, thanks very much for the advice. lots to try then!....

found a good video on youtube of a guy descending with cadel evans (must have been a sportive or a summit finish on the tour?) but it does show some good descending skills http://www.youtube.com/watch?v=TnB-z0b5XIo makes me want a camera now though!

andrewgturnbull

bompington wrote:

Thanks andrewgt. I'll print that out on a card and attach it to my handlebars for a handy quick reference next time I'm heading down Jock's Brae towards the corner at 40+mph

Personally, I never travel without the complete rbr faq....

Cheers, Andy

G-Wiz

I got much better at cornering when I owned a 500cc motorbike for a while. There's a sort of gyroscope feeling you get when you push down on the inside bar that's not so much turning as moving the wheel sideways.

It's hard to explain until you've felt it with a much heavier wheel, but I was talking about this with a few other cyclists who ride big bikes and they all seemed to know what I was on about.

It's very counterintuitive, just as you're about to sh*t yourself and stiffen up in a panic, you need to relax and just push down on the inside a bit and you just glide through.

Wet and gravel aside, if you go too fast you're in more danger of hitting the outside of the bend than slipping off if you're going too fast, so if you can find a decent bit of road where you can see what's coming all the way through the bend just get out and practice.

I wish they'd take those wooden stumpy posts out of the outside of the steep bit in Richmond park. It'd be a perfect place for it!

DaSy

In addition to pushing down on the outside pedal, push down with the inside hand on the bars. You force the bike to do the leaning, whilst keeping your weight and centre of gravity closer to the tyres contact patch.

AidanR

I found this fantastically useful (though much but not all has already been covered by Sheldon)...

http://www.flammerouge.je/content/3_fac ... escend.htm

Pokerface

I payed attention to the counter-steering thing this weekend - and you do indeed turn the opposite way before making a sharp turn at speed.

But it's a sub-conscious thing and almost imperceptible. It's not a giant gesture. If it wasn't pointed out, probably never would have noticed it.