How to Use Your Brakes

How to Use Your Brakes raking seems simple enough. You pull on the brake levers — you stop. It's not rocket science. Or is it? When you apply the brakes you set in motion a number of laws even Congress can't amend. Such are the laws of nature. Powerful. Immutable. And, thanks to a man with a fondness for apple trees — Sir Isaac Newton — useful as a tool for learning proper braking techniques.

Inertia and the Art of Not Crashing
Newton's First Law of Motion 1. (Inertia Law): A body at rest remains at rest and a body in motion continues to move at a constant velocity unless acted upon by an external force.	You and your bike are moving down a trail. That's 2 objects flying through the air. You hit the brakes. According to Newton's first law, if an object encounters no external forces, the object will keep going and going. But you've applied the brakes, an external force, to at least 1 of the objects — your bike. That leaves the other object, you, flying through the air. This situation is usually referred to as a crash and is best avoided. Here's how. The act of braking is applying what is known as a dissipative force. It diffuses the motion of the bicycle by way of friction — the brake pads rubbing on the rim. Because of your forward motion, much of the dissipative forces are gathered in the front brakes. Up to 70% of your braking power comes from them. The rest of your braking power comes from your rear brakes. This means you need to use your body and the surrounding terrain to give the front brakes some help.

Use Your Body
Our friend with the fondness for apple trees understood that it takes energy to move an object. Fortunately, your flesh and bones contain all the energy you need to move things around. Throw Your Weight Around The simple action of moving your weight back can give the rear brakes the boost they need. The faster you're going or the steeper the hill, the further back you move. You'll find experienced cyclists almost sitting on their back tire in order to get more energy on the back wheel.	Newton's Second Law of Motion 2. A force acting on a body gives it an acceleration that is in the direction of the force and has magnitude inversely proportional to the mass of the body: F = ma.
Understanding this concept is the first step in learning that braking isn't about your brakes and it isn't about stopping. It's about how you use your body and the laws of motion to keep you on the edge of control. Practice This: Find a hill that's fairly steep. It can be a grassy hill or the downhill section of a favorite trail. Just make sure there aren't too many roots or rocks to get in the way of your practicing. Find a good position for your hands. Some riders like 2 fingers on the brakes, some like 3. Do whatever feels most comfortable to you. Start down the hill on your bike, but go as slow as you can without tipping over. Make sure your feet are at the platform position, that is, at 3 o'clock and 9 o'clock with your favored foot forward. Now move your rear end back on the saddle. Feel the difference? Even subtle movements can make a big difference. In this stance it can be hard to steer, but use your body to help you steer by leaning slightly to the left to go left or slightly to the right to go right. Go ahead and move your rear end further back. But be careful! You could pop a wheelie. When this happens you've moved all of your mass to the rear of your bike.
Use Your Legs
It's in the corners that professional road and mountain bike races are won. The pros will drive their outside leg down on the pedal. (If the corner curves to the right, your left leg goes to work. Vice versa if the corner curves to the left.) Following Newton's Third Law of Motion, this makes sense. As you drive your leg down on the pedal an opposite reaction is occurring in the rest of your body. It is being sent toward the center of the bike.	Newton's Third Law of Motion 3. For every action force, there is a corresponding reaction force, which is equal in magnitude and opposite in direction.
Now, because of the force caused by the cornering and the force of you driving your weight into the corner, the actual pull of gravity is down onto your bike's tires, helping them grip the corner. You may feel the urge to hit the brakes, but fight the urge and trust Newton. If your tires have a good grip, then you'll corner just fine. If you do need to touch the brakes, do so very lightly. Remember that tapping the brakes even slightly can throw you forward and there goes the nice balance you just set up through the corner. As you exit the corner start hammering on the pedals. This balances out your weight and keeps you from oversteering.
Use the Terrain
Terrain is not as much of an issue on a road bike as it is on a mountain bike. Generally, traction for a road bike is fairly dependable. Still, as the road dips and turns, you can take advantage of these shifts in terrain to decelerate and control your bike. Banging the Berm Roads tilt when they corner. This tilt is true of highways, speedways and your local trail or rural road. The reason is simple: The tilt shifts the balance of the car or bicycle toward its center. As we saw above, this helps traction. On well-designed trails, the fast, tight corners will have even more of a tilt than normal. On extreme corners they'll have something of a raised mound following the outside line of the corner. This is called a berm. As you enter a corner you can use the berm to slow your speed and keep your bike balanced around the corner. The higher you go on the berm the more you can reduce your speed. Just don't go too high, or you'll go over the berm and into the trees. Try to stay somewhere in the lower middle of the berm. The best approach to a berm is to move your weight back, brake slightly before the corner and get ready to lean into the corner. Then, ride onto the berm, start your lean, drive your outside leg down and ride the berm around the corner. As you get ready to exit the corner, drop down the berm. Your speed will increase and you'll shoot out of the corner ready to conquer the next part of the trail. Don't Skid The No. 1 mistake people make on their bikes is to skid. Sure, it was fun when you were a kid. But it's actually an inefficient, environment-spoiling and, in fact, dangerous way to brake. Once your tires break loose and start spitting gravel or leaving rubber on the asphalt, you've lost control. Car manufacturers understand this (as do insurers) and that's why anti-lock brakes are pretty much standard on all new cars and SUVs. On mountain bikes, traction is a big problem and you can find your tires breaking loose when you least want them to. Generally, however, after you become more experienced, you can ride down stuff you can't even walk down. How? Feathering Short, quick pulls on the brake levers will help your tires get traction and allow you to roll through the loose stuff. It's a technique called feathering. As you practice you'll be able to tell just when to ride the brakes and when to let loose. Practice This: Find a steep section of trail or road with loose traction. With your weight distributed evenly, build up some speed and apply the rear brakes just until the rear wheel starts to skid. Just when you hear the rear tire cutting loose, let go of the brakes, then apply them again. Do this several times in rapid succession until you've come to a complete stop. You've just feathered your brakes to help you stop. A good way to think of braking is like the captain of the space shuttle steering her ship in the vacuum of space. Just little blasts from the steering rockets are all that are needed to bring the massive shuttle in line with a satellite or the space station. Rocks and Roots Just as feathering can help you get through the loose stuff safely, it can help you clear the rocks and roots that would like to eat you for dinner. Here, using your weight is as important as using the brakes to maintain control. Sure, you could get up some speed and just bash your way over the obstacles, but not only does this look bad, it can also cause you to lose control of the bike. Instead, make sure you have just enough speed so that when you hit the obstacle, you don't come to a stop and get thrown. Now, as you approach the obstacle, unweight the front tire by moving your weight back on the saddle. Let the front tire clear the rock. When the front tire hits the trail, move your weight forward so that the back tire can clear the rock. This is the tricky part here. Move your weight too far forward and you could do an endo. To help make sure this doesn't happen, apply pressure to the rear brake only as the rear tire clears the obstacle. This helps keep you from moving too far forward, controls your speed coming off the back end of the obstacle and sets you up nicely for further obstacles. Air Resistance Going back to Newton's first rule, we see that an object will keep moving along unless it meets some resistance. This is true in space, but here on terra firma, we have air to contend with. If you find yourself moving too fast down some long stretch of trail or road, you can stand on your pedals, bend your elbows outward, get your head up and generally make yourself as large a target as possible. The air will help slow you down. Want more speed? Lower yourself into a tuck (elbows in, head down) and off you go. Stay Loose As with any maneuver on your bike, you are best served by keeping yourself loose and ready for anything. Remember to hold the handlebar lightly, keep your knees bent, hold your head up and scan the road ahead for any trouble. And soon, you'll beat the pros at their game.