OverviewA bicycle brake reduces the speed of a bicycle or prevents it from moving. The three main types are rim brakes, disc brakes, and drum brakes. There have been various types of brakes used throughout history, and several are still in use today.Most bicycle brake system consist of three way main components: a mechanism for the rider to apply the brakes, such as brake levers or pedals; a mechanism for transmitting that signal, such as Bowden cables, hydraulic hoses, rods, or the bicycle chain; and the brake mechanism itself, a calliper or drum to press two or more surfaces together in order to convert, via friction, kinetic energy of the bike and rider into thermal energy to be dissipated.

Description of the Three Braking SystemsDISC BRAKESThe disc brake is a systematic mechanism that requires hydraulic energy in order to slow down the wheel of the bicycle. In a disc brake, kinetic energy of the wheel is converted into thermal energy to slow and make the bicycle come to a complete stop.In a hydraulic disc braking system, the disc brake is triggered by first by squeezing the brake lever towards the handlebar. By doing so, pushes down a perpendicular piston that pushes down brake fluid in a hydraulic cable, creating pressure, activating the second piston at the brake pads. The two pads then compress and come into contact with the disc brake which through friction, slows down the wheel gradually until it stops. In a mechanical disc braking system, squeezing the brake lever, pulls and applies tension to the Bowden cables. The cables then pull onto the brake pad fitted callipers, which then interacts with the disc brake, slowing the bicycle down. RIM BRAKESRim brakes work in almost the same way as disc brakes do, in that the system is almost identical, but the pads used are frictional, and the pads apply force onto is the rim of the bicycle in order to slow it down; thus the name. The friction pads in a rim braking system are typically made from leather, rubber or cork.The hydraulic rim braking system begins by compressing the brake lever and the handlebar, which using a piston, compresses brake fluid, pressurising the cable, which then pushes the pads onto the moving wheel, slowing it down through friction. The kinetic energy of the wheel in motion is transformed into thermal energy which as a result, slows the bicycle down until a complete stop.The mechanical rim system starts by first clasping the brake lever, pulling onto the Bowden cable attached to one half of the calliper. Pulling this half rotates it, until it comes into contact with the bicycle rim and through friction, eventually stops the bicycle.DRUM BRAKESDrum brakes obey the same principle as rim and disc brakes, where friction slows down kinetic energy of the wheel, and changes it into heat energy. However, the drum brake is different as it applies the friction in a different way, but like disc brakes, the heat is focused at the hub. What makes the drum braking system unique is that the systematic components are all kept inside a round, metallic drum. The drum braking system can also be powered hydraulically or mechanically.The drum braking system is also activated through the initial brake lever, triggering the springs inside the metallic drum. The springs then push the brake pads outwards , expanding inside until it comes into contact with the interior wall lining. The wall then applies frictional force on the surrounding wheel, slowing it down until it stops. Comparison and Constrast of the Three SystemsDisc, rim and drum are all types of brake systems that apply frictional force in order to reduce speed of a vehicle. The three brakes all work by converting motion energy into heat energy, but slow bicycles down in different ways. The brakes are all triggered by applying compression onto a brake lever attached to the handle bar, which makes two pads come into contact with their main brakes to apply friction to a wheel. However, the process that results in the reduction of speed in the bicycle is different in each brake. Both the rim and disc braking system utilise callipers that interact with their brake pads, but the disc brake involves the use of hydraulic pressure to transfer energy from piston to piston, while rim brakes convert kinetic energy to thermal energy through a cable. Unlike the rim and disc braking systems, by applying pressure to the brave lever in a drum brake system, brake pads inside a hub shell push outwards to apply friction to the wheel. All braking systems are able to operate with the use of hydraulics or mechanics, and are all initiated by squeezing a brake lever attached to the handlebar.Different to rim and drum brakes, the disc brake has a more complicated system and is less affected by mud and water; therefore their pads last longer and their rims can be slightly stronger. Compared to other brakes, disc brakes are able to dissipate heat energy better, and brake fade occurs more slowly, guaranteeing a longer lasting consistent stopping power. Instead of having the major components within a metal drum, or converting energy through a cable, the disc brake uses a slim iron rotor and a small calliper to hinder further movement on the wheels. Disc brakes are generally considered superior to both rim and drum brakes for their ability to undergo severe usage and repeated sudden stops without losing effectiveness quickly. In wet weather conditions, disc brakes work better than drum and rim brakes because centrifugal force can fling water off the brake disc and keep it dry, whereas drum brakes tend to collect water on the inside and rim brakes start to respond slower. In addition, disc brakes have holes in their rotor, allowing water and debris to eventually get out from under the pad. Disc brakes stop more safely than rim and drum brakes, which tend to put the bike in a spin or lock up, causing the cyclist to lose control. With high durability, great heat dissipation and consistent brake force, the disc braking system is a reliable way of stopping a bicycle. Like the disc brake, the drum brake has two brake pads and a piston. However, the drum brake system also includes an adjuster and emergency brake mechanism, all set off through the use of springs. What sets the drum brake apart from the rim and disc brakes is its design; where the components are housed inside a metallic round drum. With more parts than a disc brake, the drum brake is much harder to maintain, but is less expensive to manufacture. In addition to this, the design and arrangement of components easily enables an emergency system to be incorporated into the drum braking system. A problem that the drum brake faces that the disc and rim brakes do not is the tendency to get hotter with each use, thus losing the effectiveness and speed in which the bicycle is stopped. Because of this, the drum braking system is more prone to brake fade than the others, and experience a sever loss of brake power after time, especially regarding braking on inclines. Although the components required to trigger a halt is stored inside a drum, water can still gather on the drums interior between the outer lining and brake pads. The drum brake is the heaviest, but is much smaller than the disc brake and does not depend on hydraulic energy. The drum brake is a compact, small but complex system that works well and it cheap to manufacture, but has many problems.Compared to the design of the drum and disc braking systems, the rim brake is a simple, standard system composed of cheap, replaceable blocks. For this reason, the effort required to stop the bicycle is very little, thus the mechanical advantage of the break is much higher than other systems. Furthermore, composition of the components in the rim brake is rather straightforward, meaning that it doesnt require as much maintenance as the complex drum and disc systems. Unlike the disc and drum brakes, the rim brake has no hub and therefore bears no risk of hub overheat. On the other hand, rim brakes carry the possibility of a tyre blowout and wear and tear under heat. As well as this, mud and water wear away the rim of the bicycle, decreasing the braking efficiency of the system. All in all, the rim braking system is simple and practical that is more suited for cheaper, lightweight bikes.Preferred Braking SystemAfter researching and evaluating the three different types of braking systems, due to its superior longevity, consistent high performance and beauty I believe that the disc braking system is the best system for braking. The main problem that rim brakes experience that disc brakes do not is the wearing away of the rims on the bicycle. Compared to the drum and rim braking system, the disc braking system is able to dissipate heat better, ensuring a consistent strong brake power. Having less brake fade and better modulation, the disc braking system is proven is last much longer than the rim brake. In wet weather conditions, the disc braking system have shown to be the most capable, being the least affected by mud and water of the three. Its long lasting brake pads and high durability under extended periods of heavy braking confirm its reliability for dependable braking. On the other hand, rim brakes maintain high pressure on the rims, wearing them away. As well as that, the danger of blowing a tyre that the disc brake does not experience poses a higher risk than the effects of heat onto the hub in the disc braking system. In addition, the disc brakes aesthetic beauty compliments any bicycle guaranteeing the attention of the rider-attracted gender, whereas the rim braking system has been shown to repel such people. The disc brake is superior to the drum brake in that it dissipates heat energy better and under severe usage, takes longer to lose effectiveness. In wet weather, disc brakes are almost always dry due to the centrifugal force flinging water off, keeping it dry whereas drum brakes have a tendency to hold water in the interior outer lining. The disc brake is also lighter than the drum brake, making the bike easier to carry around; in the case where you are too lazy to ride up a hill, though it wouldnt be a problem riding up the hill since they perform better than drum brakes on inclines. The disc brake is also stronger and more durable, and easier to maintain having the components outside. Contamination and cleaning is therefore much simpler, and the annoyance of dust and cobwebs are not as problematic for the disc brake. Therefore, I have concluded that the disc brake is the most effective and reliable braking system of the three because of its overwhelming number of pros. By being able to perform the best in all cycling conditions, and proving its superior ability to dissipate heat, the disc braking system displays both durability and efficiency. Its compatibility and beauty with a wide range of bicycle models set a high standard for exterior magnificence in action. Its long lasting endurance and ease in maintenance further highlights its durability and practicality, and indicates that the disc brake is in fact the best way brake.INDEX / GLOSSARYdurabilitythe ability to withstand wear, pressure or damagehydraulic relating to a liquid moving in a confined space under pressuremechanicaloperated by machine or machinerycentrifugal forcea force arising from the bodys inertia that appears to act on a body moving in a circular path and is directed away from the centre around which the body is movinginclinea hill on an angle; slopeBIBLIOGRAPHYhttps://www.crazyguyonabike.com/doc/page/?page_id=8174The Art of Bicycle Touring (2003-2010) Neil Guntonhttp://www.bikeforums.net/commuting/769054-rim-vs-disc-vs-drum-brakes.htmlBike Forums : Rim vs Disc vs Drum Brakes (2011) ceshttp://sheldonbrown.com/brake-choices.htmlStop! / Gimme 2 Brakes (1997-2007) Sheldon Brown revised by John Allenhttp://auto.howstuffworks.com/auto-parts/brakes/brake-types/drum-brake1.htmHow Drum Brakes Work (2011) Karim Nice