Giving Your Brakes A Break

(This article was originally published in my sports page column Self-Propelled

in the July 24 to 30, 2011 issue of the Baguio Chronicle

--- a weekly newspaper based in Baguio City, Philippines.)

Brakes are designed to control your speed, not just to stop the bike.

It is important to your safety that you instinctively know which brake level controls which brake (front or rear) on your bike. In the U.S., bikes are required to be set up with the right brake lever controlling the rear brake and the left lever controlling the front brake.

The braking action of a bicycle is a function of the friction between the brake surfaces --- usually the brake pads and the wheel rim. To make sure that you have maximum friction available, keep your wheel rims and brake pads clean and free of lubricants, waxes or polishes.

Make sure that your hands can reach and squeeze the brake levers comfortably. If your hands are too small to operate the levers comfortably, consult your dealer before riding the bike. The lever reach may be adjustable or you may need a different brake lever design.

Most brakes have some form of quick release mechanism to allow the brake shoes to clear the tire when a wheel is removed or re-installed. When the brake quick release is in the open position, the brakes are inoperative. Make sure you understand the way the brake quick release works on your bike and check each time to make sure both brakes work correctly before you get on the bike.

Maximum braking force for each wheel occurs at the point just before the wheel locks up (or stops rotating) and starts to skid. Once the tire skids, you actually lose most of your stopping force and all directional control. A locked up front wheel is not steerable.

You need to practice slowing and stopping smoothly without locking up a wheel. The technique is called PROGRESSIVE BRAKE MODULATION. Instead of jerking the brake lever to the position where you think you will generate appropriate braking force, squeeze the lever, progressively increasing the braking force. If you feel the wheel start to lock up, release pressure just a little to keep the wheels rotating just short of lockup. It is important to develop a feel for the amount of brake lever pressure required for each wheel at different speeds and on different surfaces. To better understand this, experiment a little by walking you bike and applying different amounts of pressure to each brake lever until the wheel locks.

Some bicycles brakes such as disc brakes and linear-pull brakes are extremely powerful. You should take extra case in becoming familiar with these brakes and exercise particular care when using them. Applying these brakes too hard or too suddenly can lock up a when which could cause you to lose control and fall. (CAUTION: Disc brakes can get extremely hot with extended use. Be careful not to touch a disc brake until it has had plenty of time to cool.)

For most effective braking, use both brakes and apply them simultaneously. Sudden or excessive application of the front brake may pitch the rider over the handlebars, which may result to injury or death.

When you apply one or both brakes, the bikes to slow but you body wants to continue at the speed at which it was going. This causes a transfer of weight to the front wheel. This weight transfer is even more pronounced if you bike has a front suspension fork which ‘dips’ under braking, increasing the weight transfer.

A wheel with more weight on it will accept greater brake pressure before lockup while a wheel with less weight will lockup with less pressure. As you apply brakes and your weight shifts forward, you need to shift you body towards the rear of the bike in order to transfer weight back on the rear wheel.

The keys to effective speed control and safe stopping are controlling wheel lockup and weight transfer. Practice braking and weight transfer techniques where there is no traffic or other hazards and distractions.

Everything changes when you ride on loose surfaces or in wet weather. Tire adhesion is reduced so the wheels have less cornering and braking traction and can lockup with less brake force. Moisture or dirt on the brake pads reduces their ability to grip. The way to maintain control on loose or wet surfaces is to go more slowly to begin with.

Do not rice the brakes since overheated pads and rims can cause fading of the brakes or tire blowouts. To slow down, brake regularly for short intervals. For panic stops, learn just how hard you can brake without having the bike skid out from under you. Use both brakes but be cautious about applying maximum force to the rear brake. As you brake hard, the center of gravity tries to move forward and most of the force is applied to the front wheel which therefore has more traction. Panic squeezing of the rear bake will lock up the rear wheel and can cause a skid. Be particularly careful when braking on curves, sand and gravel.

Under wet conditions, the sopping power of your bike (as well as the brakes of other vehicles sharing the road) is dramatically reduced and your tires do not grip nearly as well. This makes it harder to control speed and easier to lose control. To make sure that you can slow down and stop safely in wet conditions, ride more slowly and apply your brakes earlier and more gradually than you would under normal, dry conditions.

Make it a point to check the brakes every time you ride and keep them adjusted properly so that when a difficult braking situation occurs, you will have plenty of reserves. Replace cables that are beginning to fray and housings that are developing too much play.

Until then and have a safe ride all the time. Put on that cycling helmet each time get on your bike. Remember: YOU CAN BEAT THE EGG WITHOUT BREAKING THE SHELL.* (SP9)