Friday, November 6, 2015

A Simple Ways to Improve Your Braking Skills !

When you drive your car and you need to emergency brake to avoid a smash, I bet you stomp on the pedal and let the ABS do the work. And if you need to avoid a child at the same time, just steer. So easy! Of course it wasn’t always like this. Cars used to be able to manage front wheel skids under braking (easy) in the dry, rear wheel skids in greasy, wet conditions (difficult) and 4 wheel skids on snow and ice (scary).




If you tried to steer under hard braking, one of two things happened: it went straight on (usual) or it went completely out of control (rare). Trucks with semis routinely jack-knifed when braked hard in the wet or downhill, collecting a few cars in the resulting smash and maybe falling on one side to finish off. The lucky drivers in those days still got metal armor so even when they got it wrong, they had a chance of walking away from the accident. Then there’s you on your bike...



On a motorcycle good braking skills prevent a dramatic moment becoming a serious accident. I believe that learning how to get the best braking performance in any circumstances is one of the key skills to riding safely at speed. When you skid, and believe me you will skid, will you handle it or will you come off? If you can’t handle a skid, you’ll be scared to brake hard. If you’re scared to brake hard, you won’t avoid the crash.

Locking up, skidding and sliding are scary thoughts for many bikers. Some will go to almost any lengths to avoid these things happening. Are they safe riders? If they stay within the limits of their abilities – yes. Are they quick and safe? – NO. If you never explore the limits and how to cope with them, you will never have the margin available of someone that has. It is a personal choice. If you want to push the envelope – read on !

Braking Skids




Locking the rear wheel is easy under braking in any conditions. Locking the front is remarkably difficult on dry asphalt... but all too easy when it is really slippery. Usually it is changes in front tire traction that will catch you out.


Start and stop a rear brake skid




Start in the dry. A little harder to start the skid, but easier to catch. WARNING – if the bike gets out of line in the skid then regains rear traction, it can pitch you off! Start going dead straight at slow speed. Take a stab at the rear brake and let it off right away. Not too bad huh? You can build up your brake hold time and the speed as your confidence grows.

Getting out of line. When you lose grip with the rear tire, it may try to move out of line in either direction. The worst case is if you lock the rear wheel while braking the front tire, because the rear end starts trying to pass the front! If you regain rear grip with the rear not in line with the direction of travel, you will lose it. The standard advice is to hold the rear wheel locked until you have straightened the line, then release the back brake to kill the skid. It sounds right, it does work, but instinct is against you.

Unless you practice this kind of skid recovery regularly, you will not perform under pressure in an emergency. I advise that you avoid experimenting with this region of skid control until you have practiced straightening the line by steering into power slides, as this is easier to master first. In my view it is better to become practiced at killing rear skids as soon as they start. It’s in line with your instinctive response and will avoid the getting out the line issue altogether.


Start and stop a front brake skid





You have been warned about the kind of trouble this can get you into, right? Well they weren’t joking and you need to go gently here. Front-end skids are definitely harder to catch than back end ones.

You want to find a surface with limited grip. Avoid really slippery stuff like oil. Some super smooth ‘polished’ surfaces can be about right or smooth wet asphalt. I prefer to start on a good hard flat dry dirt surface. Start just skidding just a bit from a heavy front brake application at slow speed. Keep your feet on the pegs until stopped. Tempting as it is, riding feet down ‘just in case’ will ruin your balance and control.

One thing you learn quick doing this is how much stability a rotating rear wheel provides. Because it is fixed directly in line with the axis of the bike frame, it works as a gyro to keep you upright and heading straight. The gyro force increases as the speed rises. But this doesn’t stop the back wanting to pass the front, so there are forces at work trying to get that front wheel out of line. Once locked the front wheel has no gyro action and is easily turned. Do this at speed and a small surface irregularity seems to generate enough reaction to tear the bars out of your hands. You have been warned! The only way to deal with a front-end skid is to let off the brake NOW. Reapply it with a bit less pressure to avoid locking a second time.

When you have done this deliberately a few times under controlled conditions, three facts come through : Front brake skids don’t happen as easy as you think, but when they do... Front skids are scary and dangerous - Letting off the front brake stops the skid IF YOU ACT FAST

But there’s a little problem :

Letting off the brake doesn’t come easy when you’re heading for a truck !

You may think I’m crazy...

You may think I’m crazy telling you to go out and deliberately induce skids. But if you ride a motorcycle and want to go on living, you only have 3 options :

1. Accept your braking skill limitations, ride conservatively and concentrate on avoiding the hazards caused by others.

2. Become an expert braker. You will still have limitations but your straight line braking performance will be better than a car in the dry and about the same in the wet. Because you brake hard, you will lock or start to lock a wheel from time to time. You will deal with it confidently and correctly.

3. Get a bike with good ABS. You will still have limitations but your braking performance will be at least as good as a car under all conditions. You will concentrate on ‘reading the road surface’ to be aware of the level of traction available.


A Personal View on ABS






I don’t want to see ABS on the track. Racing is a test of rider skill and braking is one the key skills in riding. Tracks with severely reducing radius curves and ‘3 dimensional curve entries’ that shift from extra traction in the upslope to reduced traction over the crest and into the down-slope, call for precision and delicacy that only the very best racers can achieve. If you have practiced the way Keith Code recommends, screw up on the track and take a fall... you usually get away with it. If you screw up and take a fall on the street, you can hit concrete or steel rather than straw bales... before you get crushed by the car!

If I rode a motorcycle everyday on the street as a job or even just as a commute to carve through peak time traffic snarl-ups, I would demand ABS. For a ‘must do’ ride where you have to deal with any conditions and unexpected hazards and you don’t want to end up totally drained, it’s a great tool.

For a fun ride situation, it’s more difficult to make a choice. On a tourer, doing hundreds of miles, give me the ABS, no question. For a short ride on a nimble sports bike on my favorite piece of road, I don’t want the ABS. If I can choose the weather conditions, checkout the asphalt the same as at the track and basically reduce the number of variables, then the challenge of relying only on my own skills is hard to resist. Sadly the opportunities to ‘do your own thing’ on the public highway get ever less. I get most of my fun off road now, without ABS.

ABS is a tool not a miracle worker. It will react to give the best braking available but if that isn’t enough because of your misjudgment, you still crash. Go into a curve too fast, apply brakes, go off the road. No change there! ABS is a worthwhile addition to a street bike and will probably become standard over the next decade. Unlike on the track, the street is a hostile environment for motorcycle riders so we probably deserve one or two assists to improve our chances !


ABS Braking




So you bought a bike with ABS ? Great, but it still doesn’t brake like your car. Motorcycle ABS systems vary a bit but they all have characteristics you need to get familiar with. Read the manual. Do front only and rear only braking hard enough to get the ABS to ‘chirp’ or whatever you want to call the little valve hammering noise.

Even if your bike has linked brakes, find out what using one control at a time feels like, they’re not the same. Now test it out using both hand and foot. Some bikes tend to snatch as the ABS bites and then steady down. Others just feel squirrelly all the time the ABS is working. Learn to love it whatever it’s like. One day you’ll be thankful.

Remember how you were told how you could brake and swerve around an obstacle at the same time in your car with ABS? Don’t try this on your bike!

All ABS systems are not the same. Braking while well banked over is one area where there are big differences. The technology keeps evolving, so don’t get misled by out of date reviews. Gently explore braking in a turn until you know for sure how the system on your bike copes with it.

Don’t believe the people who tell you that ABS stops you riding to your top skill level. If you ride like a trackstar, your ABS will chirp for the odd second on a bump or ripple, when you would have heard a squeak from the tire on a non-ABS machine. In fact you can use it deliberately to test that you can accurately judge maximum available braking by just squeezing on a little extra and making the ABS come on.

Hard Braking


Most people don’t brake hard enough. They are so scared of a lock-up, they only use 60-80% of the available performance. This has been proved by studies in Austria and elsewhere. Did you ever lock your front by mistake in the dry? It’s really, really rare although people are scared of it. Even in the wet it’s surprisingly hard to lock the front.

So practice. Be prepared to use more brake. It’s the unexpected slippery bits that catch people out : mud, leaves, sand, gravel, oil, and gratings. To be frank using only 70% of available braking isn’t going to save you when you hit one of these unexpectedly, so why try for the false margin ? Learn to use all that front brake confidently. Use it when you don’t need to, just to stay in practice. Keep the feel.
Best answer for riding on the street: learn, practice, improve your braking skills... and have the ABS as back up.

Points to watch


The more slippery it gets, the less traction that’s available. With plenty of grip and plenty of brake you transfer virtually all of the weight of the machine onto the front tire. The rear brake just can’t contribute much under these conditions. Under low traction conditions you can’t get that kind of weight transfer so the braking wants to be shared. In low grip conditions use equal amounts of front and rear
gingerly. With more traction increase the proportion of front brake effort. You will find that you never use anything more than moderate rear brake under any conditions. If the conditions are good enough for the machine to accept more, you should be using more front. That will keep traction margin on both tires.

Gradient affects braking more than you think. It’s amazing how fast you can decelerate going up the mountain and how damn hard it is to stop going down! If you live on a plain and you’re not used to such roads, watch out ! When the opportunity arises, explore the effect of gradient on braking and file the information away in your mind for future use.

My biggest braking problem



The braking that I have never managed to get properly sorted involves going down one of those steep mountain roads where straight sections are linked by blind hairpin corners in a zigzag. The region that sticks in my mind is the French Alps but there are similar sections in many other mountainous areas.

Braking and turning through the downhill left-handers is always the worst. Drivers of underpowered 4 wheelers on the way up don’t want to slow down more than they have to, so cross the center line to increase their turn radius. There are always pebbles on the outside of the turn ; get onto those and it’s like ball bearings. The drop of 200-300 feet to the next piece of road lower down concentrates the mind
on riding a conservative line and speed while watching out for drivers stealing your piece of asphalt or those who have blocked the lane, stopped to admire the view.

I originally thought it was these distractions that were upsetting a smooth slow down followed by turning under braking to hold the speed steady. But later I discovered that it was turning under braking at 10-15 mph that seems to be the dominant issue. This is an awkward speed range where neither counter steering nor low speed maneuvering techniques work well. Doing it under braking to hold the speed on an 8-10% downgrade just adds to the difficulty.

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