Control Your Speed: The Brakes
In cycling terms: a brake is simply a component or system designed to slow the bike down, and unsurprisingly this slowing down will result in eventually coming to a halt (unless you are coasting down an eternally long hill, or pedaling while braking).
Slowing down and stopping are just as important as moving forward. Often overlooked by the everyday rider, effective control of the brakes is just as much of a skill as pushing hard on the pedals or flying between trees. For some, specialised kinds of riding, brakes are considered not always necessary (track racing & BMX bikes, to name a couple), however with the vast majority of bicycles being ridden on the road, particularly in urban landscapes – brakes are seriously important!
An important choice to made when sourcing components to build a bike, the brakes make a huge difference in the ridability: a well set up braking system can inspire confidence and provide you with the safety blanket you need when pushing the limits (when the traffic lights allow). Knowing you are covered by an effective slowing and stopping system can make riding much less stressful and encourage you to ride faster.
On the other end of the spectrum, a poor braking set up can not only be extremely dangerous but can also add anxiety to your ride. This is not only in terms of how strong the brakes are, but how much adjustability they have, how predictable they are, how easy they are to apply and moderate, and, of course, how well they cope with changing conditions.
It is UK law for all bicycles on the roads to have two functioning brakes. Some braking systems are more conventional than others but as long as there is a brake for each wheel you are good to go. For example: a front brake with a fixed-gear wheel (see Section 10), or a pedal-back brake (Section 8) are both legal ways to stop.
In this section, the fundamental components that make up different braking systems will be broken down and explained.
Somewhere To Sit: The Frame
Rolling: The Wheels
Control Your Speed: The Brakes
Make It Go: Transmission
Tools & Accessories
A brake lever is located on the handlebar of the bike, and is responsible for allowing the rider to operate the brake remotely. Traditionally, each lever controls a separate brake, so if the bike only has one brake, then it will also only have one lever.
In the UK, the standard format is to have the lever controlling the front brake on the right hand side, and the rear brake on the left (unlike in the USA, for example, where the reverse is true). However it is down to rider preference, and there is no difference to real performance. If the bike only has one brake lever then it can be positioned on either side, depending on which is most comfortable for the rider.
A standard bicycle brake lever is connected to the brake cable (see Section 2), and operates by using a pivoting lever that pulls the inner brake cable, whilst fixing the outer cable in a stationary position – resulting in the inner cable being pulled tight.
The key components of common a lever are:
The pivot - The fixed point around which the lever blade rotates;
The lever blade – The moving part of the lever that the rider operates;
The clamp – The collar that is used to mount the lever body to the handlebar;
The barrel adjuster – The part where the cable is connected and allows adjustment;
The lever body – This is the main section of the lever that houses the other components;
The return spring – This is responsible for ensuring the lever blade returns to the ready position.
These are the fundamental components and jobs of a cable brake lever. For an explanation of hydraulic levers, please refer to Section 6, or a description of rod brake systems please refer to Section 2.
There are many different lever types, which can be chosen depending on the rider’s requirement, preferences or the application where it is needed. Many bikes and brake systems only have one type of lever that is compatible, so it is partly down to choice, but also down to the type of brake system that has been chosen.
The most common brake lever types are as follows:
The standard flat bar lever – This is the most common type of brake lever, as flat handlebar bikes use it. The style, shape and material vary hugely depending on how specialised the bike is, however, the most common design is an aluminium body with an aluminium lever blade. The cable connects to the inner side of the lever (facing the centre of the bike), and the lever is flat, with the lever blade facing outwards (away from the bike);
BMX lever, or Trigger lever – This is a specific type of flat bar lever, originally designed for BMX bikes, and tends to have a much larger, stronger lever body with a shorter and thicker lever blade. The reason is that on a BMX you need to generate a lot of stopping power, but the construction has to be as compact as possible as to keep it out of the way when performing tricks. BMX levers generally look like a much smaller, stouter version of a flat bar lever. BMX levers are becoming popular with single-speed bikes and fixies too, as the lever design allows a very minimal look, and keeps the handlebar cleaner than with a traditional flat lever;
Drop bar brake levers – Unsurprisingly these levers are designed to be used in conjunction with drop handlebars. Using the same fundamental mechanics as a flat lever, the design and shape allows them to be mounted towards the top of the bend of a bar. The lever blade on a drop lever tends to be much longer, as well as being curved to ergonomically fit with the curvature of the handlebar. The lever blade is longer so that the brake can be used from more than one position on the handlebar. In contrast to the outward pointing flat bar lever, the drop bar lever actually points down with the lever blade facing the ground. Most drop bar levers today have the cable connecting to the lever from the rear of the lever, so the cable actually runs along the handlebar up into the lever body. In comparison the older style levers have the cable visibly connecting to the lever body, the same way a flat bar lever does;
Aero levers – in contrast to the above types, these levers usually attach to the end of the handlebar through the use of an expanding plug that slides into the handlebar, as opposed to a clamping method. These levers are designed for aerodynamic handlebars - usually forward facing, for the likes of time trials, triathlons or track racing. This is not to say you cannot use them on a regular bike, and it is becoming increasingly popular, as bullhorn style bars are used more frequently. Aero levers are a good solution where there is no room on the handlebar to clamp a regular lever;
Dual levers - Or suicide levers, as they are affectionately known, are designed to be used on a drop bar bike, but also with a separate lever blade coming off the body that can be accessed on the flat part of the bar. In theory, these levers are great, as they allow the rider to use the brakes, whichever position they are in. However, in practice these levers are generally very unreliable. This is partly due to the material they are made from (cast aluminium), which allows the levers to flex a lot, as well as the design being flawed due to the top lever not being directly connected to the cable pull system. So, overall, although they may work in some cases, they are not very reliable and often fail over time. Since the cross-top lever has been introduced, the dual levers have mostly been consigned to history;
Cross-top levers- These are essentially flat bar levers, but the way that the lever pulls the cable outer housing allows the cable to run all the way through the lever – usually on the way to a drop bar lever. This essentially means you can have a lever on the flat of the handlebar as well as a drop bar lever, meaning you can ride in either position safely and confidently, knowing the brakes are always accessible. Cross-top levers were originally designed for cyclo-cross bikes, where the rider may be in any position on the bar depending on the terrain. Due to the minimal and simple design, cross-top levers are becoming a popular replacement for flat bar levers.
As well as the different lever types and designs, one factor that is not obvious, or often even distinguishable, is what’s called the pull ratio. This is often the forgotten variable in any brake lever, but ultimately it can dictate which levers are compatible with which brake systems. Although cable brakes all run the same method of pulling the inner cable, different lever systems pull the cable by different amounts and with varying force. It is important to match up the pull ratios when pairing up levers and brakes, as failure to do so can cause over-pulling (when the lever can be pulled much too far before the brake applies), or under-pulling (when the brake lever does not have enough movement before the brake is applied – making it very hard to brake with force).
Generally, the lever is attached to the bar via a clamping method. The most common forms of this include the hinge clamp (mostly BMX and cross-top levers use these) and a circular collar clamp, where the lever is threaded onto the end of the bar and slid along, then tightened in place. A wedge collar is common on drop bar levers, and involves the lever being attached to a collar, then when tightened contracts and locks into place. The standard clamp diameter for brake levers is 22.2mm.
More modern brake levers are often coupled with gear shifters in the same unit. This is the case for both flat bar and drop bar levers. The most common types of these are the Shimano STI (or Shimano Total Integrated) shifter and the Campagnolo Ergo shifter. These all-in-one units require just one clamp on the bar and result in a neat package whereby the brake lever and gear shifter all operate independently but are grouped in the same package – making the bar much less cluttered as well as freeing up more space for other accessories, (such as bells, lights, speedos and GPS systems).
Repair & maintenance tutorials:
The brake cable is responsible for transferring the energy the rider gives, in the form of pulling the lever, to the brake caliper. Brake cables are directly connected to both the lever and the caliper and traditionally consist of two main components: the inner cable (or wire), and the outer cable (or housing). The system relies on the transfer of energy to be through the movement of the inner cable, while the outer cable remains static. Before brake cables were adopted, the same principles of energy movement were applied in the form of rods. These rod brakes essentially are solid poles that work on hinges and pivots to transfer energy from handlebar to brake.
The inner brake cable is made from a number of stainless steel strands, which are tightly wound into a single cable. Slightly thicker than gear cable, the idea of the brake cable is to reliably transfer a large amount of force to the brake itself. Although manufactures claim that the inner cables are pre-stretched and bedded-in already, this process continues when they are fitted to the bike. So although a brake cable can be perfectly tensioned on installation, it will almost definitely need to be re-tensioned once the cable is further stretched. This process should only need to be done a couple of times before the cable is settled at its final length. Cables are often glazed with a light layer of silicone-based lubricant or grease, which is to ensure the inner cable continues to move freely inside the housing even when there is a bend or kink.
On one end of the inner cable, there is what’s called an anchor. This is essentially the fixed part of the cable that is located in the lever, and provides purchase on the cable so it can be tensioned through movement of the anchor, or handle on the inner cable, if you like. These anchors come in a couple of variations for various brake levers. The standard cable end is a metal cylinder that forms a right angle to the cable, often is called the hammer type, as it resembles a mallet. Road bike brake cables have a much smaller anchor, as they are located inside drop bar levers. The final common type is the traditional road bike cable nipple, which is shaped like a pear; this is designed for older style levers.
The outer cable is the cable most visible to the eye. As the name suggests it runs over the top of the inner cable like a sleeve that houses the movement of the inner cable. The outer cable is theoretically stationary, however this is not to say it cannot bend, but it has to stay stationary in relation to the cable inside. The most common outer cable is made up from a steel weave, which is tightly wound into a hollow casing with a plastic sheath running through the centre, which accommodates the moving inner cable. A plastic outer layer, to seal it off from the elements and combat any potential corrosion, then surrounds this cable. Other styles of outer cable are also available, for example the linear cable, where the steel casing is not wound, but runs parallel to the inner cable, this is designed so that if the cable is twisted or scrunched up the inner brake cable will remain free, whereas with a coil-wound housing the brake cable will be restricted as the cable twists. These more specialist cables are most often found on bikes where the bars need to spin around the frame, such as BMX.
Other types of outer cable also exists, such as the use of solid metal rings or cylinders, which make up the protection of the inner cable, while allowing the inner cable to slide beneath (picture a dried macaroni necklace). Outer housings are available in all the colours of the rainbow, so you can get creative with the colour scheme of your bike.
One neat invention that employs the use of cables and moving metal plates is a detangler or rotor, or most commonly, gyro. This is a system whereby a pair of standard brake cables is attached to a metal plate, which is then located within another metal plate. Complicated as it may sound, these systems are relatively straightforward and have been designed so that the handlebar can spin as many times as desired without any cables becoming tangled or limiting movement. Most often found on BMX bikes (in the late ‘90s).
Repair & maintenance tutorials:
3. Rim Brakes
The rim brake is a braking system that is located on the outer edge of the wheel, and makes use of the wheel rim as a friction surface. Rim brakes are the most common type found on bikes for the road. The idea is for a brake caliper to clamp pads on to the flat outer surface of the rim, to produce friction and slow the rotation of the wheels. Rim brakes have been around for a very long time, and although they describe a basic method of braking, the difference in rim brakes is huge and varies massively depending on what riding they are for, or what bike they are fitted to.
Below are the most common types of rim brakes:
V-brakes are actually a Shimano product, but commonly this term is used to describe a direct-pull cantilever brake. These brakes are common on hybrid style bikes as well as slightly older mountain bikes. Variations are also commonly found on touring bikes, cyclo-cross bikes, racing BMXs and entry-level mountain bikes. This braking system consists of two pivoting cantilever brake arms that are fixed to lugs or bosses on a frame or fork, located either side of the rim. On each of these arms there are mounting points to which the brake pads are fixed. The outer cable is then fixed to one of the arms (usually through the use of a cable noodle), while the inner brake cable is fixed to the opposing arm. This means that when the brake lever is pulled, the two brake arms clamp together, sandwiching the rim in-between.
Traditional (or centre pull) cantilever brakes again are made up of two main brake arms that hold the pads, and mount to the frame or fork either side of the rim. This type of canti’ brake relies on a bridging cable to attach to the main inner brake cable. This cable attaches to the top of both arms, and relays the movement from the brake cable to the brake arms. These brakes are most often found on older style mountain bikes, cyclo-cross bikes and touring bikes.
Caliper brakes are not mounted on lugs/bosses, but instead are mounted just above the wheel, on the top of the fork or bridge in the rear frame tubes. This type of brake hangs down from above, and uses the cable tension to move two arms and clamp the rim in one motion. Imagine a crab’s arms closing in on the rim from both sides. Commonly used on road and racing bikes, caliper brakes are relatively small units, and easily replaceable. Due to the skinny nature of road tyres and rims, these brakes are generally very narrow, so only suit a certain tyre and rim size. The attaching bolt on the topside of the brake caliper provides a central pivot point (for single-pivot brakes). However dual-pivot caliper brakes have now taken over from single-pivot caliper brakes. The main difference is that instead of there being one pivot point for the brake to clamp around, there are two points. The reason for this is that the brake movement is firstly much more adjustable, as it means spring tension can be easily shared between sides, and secondly it provides the brake caliper with a much more lateral motion when clamping the pads onto the rim, as opposed to an arched path.
There are more types of specialist rim brakes, but the above covers the most common types used today.
4. Disc brakes
Disc brakes make use of a rotor (or disc) that is mounted to the hub of the wheel. This disc is completely fixed to the wheel, so the disc matches the rotational movement of the wheel. A disc brake makes use of a much smaller caliper than a rim brake, which is mounted to the frame or fork in a fixed position and allows the disc to run through the centre of the caliper, where two pads then clamp onto the rotor, causing friction and slowing the disc and wheel down.
Disc brakes were originally designed for off-road usage, as having the braking system out of the way and in the centre of the wheel meant that riding conditions didn’t have so much of an effect on the braking performance. Rim brakes are fine on the road, but when you introduce large amounts of mud, clay, sand, water and other substances to the rim, the brakes tend to struggle as well as build up a huge amount of mud. A disc brake also allows absolute freedom to fit any size or style tyre or rim on the bike, as brake clearance is no longer an issue. For off-road cycling, therefore, the advantages of disc brakes are large. However, disc brakes are becoming increasingly popular on road-going set ups, although the practical implication is that the brakes are more powerful. This is often not a useful advantage over rim brakes, so can often be viewed as more of a aesthetic statement – because lets face it, they look great!
There are two main types of disc brakes: one operates through the pulling of a regular brake cable, and the other type operates through the use of hydraulics (please refer to the hydraulics section).
One big advantage of using a disc brake set up is that it houses all the braking elements in one place, meaning that the parts that are worn out are also contained. The rotors can be swapped and changed easily, and the pads are also easily replaced. Although the pads can seem expensive compared to regular rim brake pads – it is important to bear in mind that the pads and rotors can both be easily swapped, and it does not affect the life of the rest of the wheel. In contrast, with rim brakes the rims do wear down, particularly on carbon wheels or in muddy or sandy conditions. When a rim reaches the end of its life, things get much more expensive and complicated – a wheel rebuild or a whole new wheel is needed! Also with a disc brake set up, if the rim is knocked out of true or has a slight buckle, it is not so much of an issue, and it certainly won’t slow you down as much as a rim brake set up.
In terms of actual braking power, disc brakes do produce more stopping force. However it is almost useless to generalise amongst brake types, as the range of disc and rim brakes is so huge that it is better to compare models or specific set ups.
The most commonly found cable-operated disc brakes run at the same pull ratio as a direct pull cantilever brake (or V-Brake), so levers are completely interchangeable. However that is where the easy integration ends.
As previously explained, disc brakes can only be fitted onto wheel hubs with special mounts. The mounts are found on the non-drive side (left hand side from the saddle) of the outer hub shell.
There are two common mounting systems:
The most common system is called the 6-bolt design, characterised by 6 threaded holes on the hub shell, facing away from the bike. These holes are evenly spaced and require m5 allen-key bolts or Torx t25 head bolts. This is by far the most common method, and is internationally recognised across all manufacturers as the standard disc-to-hub mounting system.
The other system is manufactured by Shimano, and is called the Shimano Centrelock Splined system. For this system, the hub shell has a spline, which the disc then slides over, and is held in place by a lock ring. Theoretically, the Shimano system does make a lot of sense, for two main reasons. Firstly, the disc is easy to remove and replace, as it is one bolt to undo/tighten, rather than 6. Also, it tends to be the case that the splined discs are more easily located in the exact centre of the hub, whereas with the 6-bolt design there often is a slight amount of movement until the bolts are tightened.
However the original 6-bolt method does the job perfectly and is by far the most common, so remains the standard.
The other requirement when fitting a disc brake is mounts on the frame or fork. Much like the hub situation, there are two main mounting systems. Both of which require lugs, or brake bosses, on the frame. The first is the IS or International Standard mount, which is the most common overall. This mounting system is easy recognisable due to the fact you can see through the two holes on the mount. These bolt holes also face out towards the side of the bike. The other mounting system is called the Post Mount system. This system, again is made up of two bolt holes, however these holes face backwards from the bike, perpendicular to the IS mounting system.
Different manufactures use different mounting systems, but adaptors in all sizes and specifications are available, so compatibility between brake and frame/fork is never a big issue.
The overall variety of different disc brakes and discs available is massive, there is a type of disc brake out there for almost any type of riding, so be sure to look around and find what works best for you – and remember, bigger does not mean better!
The brake pads are essentially the part of the braking system that is responsible for causing friction on the friction surface (wheel rim/disc, etc.).
Over time, as the brake is used, the pads will slowly wear down. Different conditions and use will dictate how long the pads last, for example, in dry and clean conditions the pad will last a lot longer than on muddy and/or rainy roads, where grit and dirt can easily get onto the rim or disc. The pad life is also down to how the bike is ridden; bikes that are ridden hard and fast and are constantly slowing from high speeds or braking fast will go through a lot more pads than those of a steady rider.
On rim brakes, the brake pad is easily visible to the eye, so it is simple to check how much life remains in the pads. With disc brakes, it requires a bit more energy to inspect the pads but it is still possible without taking the brake or wheel off. The front brake pads wear out more quickly due to the forces on them being greater, however, most riders prefer to use the rear brake a lot more, so in reality it is these pads that need to be replaced most often.
With rim brake pads, the design can differ slightly, but the key defining feature is the mounting system, as each type of rim brake demands a different style of brake pad. The actual compound of the rubber does vary with some different specialist applications, such as steel rims or wet weather.
Each disc brake brand has a different fitting system, so you have to buy specific fitment pads depending on the brake you have. Apart from this fitment, the other variable is the material that the pads are made from. The two main material types are Sintered (metal) and Organic (resin).
Hydraulic systems are an alternative to the conventional cable system, or the outdated rod system. Hydraulic brakes are designed for much more demanding riding disciplines. They allow us to stop much harder and more consistently at much higher speeds.
As with any brake system, the goal is to remotely control a brake system or caliper from the handlebar. However with a hydraulic system, the force is not transmitted through an unstretchable cable or an inflexible rod, but instead through incompressible fluid.
Hydraulic brakes rely on this fluid to move through lines, or hoses from one point to another. These points are the cylinders, of which there are two main types:
The master cylinder is found at the lever, and is responsible for controlling the fluid throughout the rest of the system. As the lever is applied by the rider, the master cylinder compresses and fluid is then forced down the hose to the slave cylinder which is located in the brake caliper. The slave end of the system may have many different cylinders within the caliper, which are known as pistons, or pots.
The hydraulic brake caliper can take many forms, depending on the style of brake. Most traditional hydraulic brakes are in the form of a disc brake system (see Section 4), so the calipers are located in a fixed position on the frame or fork surrounding a disc attached to the wheel. While different types of hydraulic systems are also available, such as rim brakes and hub brakes, the principle of transferring forces through fluid between cylinders remains very much the same.
As explained above, the number of pistons varies depending on the system design. The most commonly used system is two pistons, one each side of the rim or disc, known as a twin pot set up. However, other systems are available with more pistons, such as 4 or even 6. Although the number of pistons a system has is a fairly good indicator of the power it generates, there are many other factors to consider, mainly the piston size, as well as the pad contact area size. For example a large twin pot caliper can actually generate more stopping force than a 4-pot design.
The fluid that fills the system varies between manufacturers and applications. The most commonly found fluids are either DOT (originally Department Of Transport) fluids, or mineral oil. DOT fluid comes in different ratings, which depend on the chemical make-up of the contents. The most common ratings of DOT fluids are 3, 4 and 5.1, each of them possessing different characteristics, strengths and weaknesses. Mineral oil is generally a term used to refer to a manufacturer’s own fluid, which can vary slightly between brands, but has very different properties to the DOT range. The most important thing to remember when dealing with brake fluids is that mineral and DOT fluids cannot mix under any circumstances. It is possible to mix DOT fluids (except DOT 5), but it is not recommended as it can create an unpredictable change in the braking system.
Perhaps the biggest drawback to using hydraulic brakes is the process involved with bleeding, initial set up and adjustment. With cable braking systems, brake adjustment can be simple and straightforward, however with hydraulic systems it can get messy. For starters, if there is any air inside the braking system, then this means that the system will have to be bled, which is the process whereby any air in the system is purged and replaced with fresh fluid.
As the pads on any brake system wear down, this will increase the distance the lever will have to travel, as the gap between the pads and the contact surface increases. With a cable braking system, the adjustment can be very simple, but essentially involves re-tensioning the cable. However if the pads on a hydraulic brake system wear down, then more fluid will have to enter the system, so as to account for the excess lever stroke. This can be done in two ways, depending on the system. With most hydraulic brake systems, there is a reserve (or reservoir) of fluid connected to the master cylinder, which automatically tops up the system when needed. Alternatively, if the system is a completely sealed line, with no fluid reserve, then the brake will have to be manually bled every time that the pads wear to a point where the feel of the lever changes.
The hoses on a hydraulic brake system are larger in diameter than conventional brake cables. Most commonly the design consists of three main layers. The inner layer is usually Teflon, and this is the internal hose that is responsible for keeping the fluid restricted within the system. The middle layer is usually made up of a Kevlar-based material, and its job is to armour the inner casing, and tightly restrict it so that when the pressure on the inner hose is increased, it does not split or bulge. The middle layer is there for structure, strength and to deflect the pressure. Finally, the outer layer of the hose is simply a tough casing, to protect the line from any damage or external factors, such as weather and elements, as well as keeping the other layers all tightly compacted and in position. Other more specialist hoses are available that make use of other materials, such as stainless steel braiding.
The main advantage of using hydraulic brakes over other methods is the potential for huge stopping power. Hydraulic systems can transfer huge amounts torque and force, which can be directly applied to a friction system to benefit from greater stopping power. This is the reason that pretty much all motor vehicles make use of hydraulic brakes, from Formula 1 cars to diesel trains to mopeds. Another big plus is the potential for moderation, as there is very little friction in the transfer of power, which means that the brakes can be modulated smoothly without dips in control, regardless of lever stroke position or power transfer. Also, once the system is fully set up and bedded in, it is sealed, so riding conditions very rarely have an impact on the brake, whereas dirt and sand and water can all clog up the moving parts of a cable system.
The disadvantages of hydraulic systems include: they are much more costly, both in initial purchase, parts and maintenance; as explained above, they are tricky to adjust, and can be damaged if you don’t know what you are doing; and finally, they are not very easily fixed or repaired without advanced tools, so are almost impossible to fix if something goes wrong during a ride.
7. Drum brakes
Drum brakes are a traditional style of brake. They are actually located on the wheel hub and are specialist parts, so you cannot fit a drum brake to a bike unless you change the hub first.
Although vintage style traditional drum brakes are operated via rods, today all drum brakes are operated through the use of a standard brake cable set up. As the inner brake cable is tensioned, an arm on the drum brake pivots around an axis. As this arm moves, the mechanism inside the drum causes shoes to move in an outward motion (expanding, if you like). The internal fiction pads within the system are known as the shoes. The components and shoes are all encased in an outer drum, so as the mechanism moves the pads outwards they create friction by coming into contact with the outer drum.
With a drum brake, the inside edge of the outer drum is the braking surface and the shoes that interact with it are essentially the pads.
The main reason drum brakes are used, and perhaps their biggest advantage, is the fact that the brake is a completely sealed unit which means that the braking system does not produce dust or dirt, as many rim brakes do if the conditions are poor.
The drum and shoe set up also has a much longer lifespan than other types of brakes. The drums do not corrode with use, as with disc and rim brakes, and the shoes are very hard wearing and long lasting. This is great, as besides the brake adjustment and cable tension, no maintenance is needed.
Drum brakes are also very predictable, so rain or shine, hot or cold, you know exactly how the brake is going to react to application.
However drum brakes do have drawbacks: Firstly, the braking force they generate is not as great as other types as the friction that the shoes and drum create isn’t nearly as much as a rotor and pad or rim and pad. This is because the shoes are an extremely durable metal composite, unlike rims that make use of soft rubber.
Although drum brakes can often be found on older bikes, they are not commonly found on new bikes, apart from some ultra-low maintenance built bikes, such as shopper bikes, town bikes or Dutch bikes. Because of the design of the drum, a specialist hub has to be used, so standard parts are not compatible. When building a bike up, one of the main criteria is usually to be serviceable and parts to be compatible, which is why drum brakes are not as common as other brake types on the bikes of today.
8. Coaster brakes
A coaster (or pedal back) brake is a type of hub brake that is exclusively for the rear wheel. The reason it is only available on the rear end of a bike is because it relies on the pedals to control its operation. Whereas traditional brakes rely on a lever or remote control, the sprocket on which the chain controls a coaster brake.
As the brake mechanism is fully enclosed within the rear hub, it is often not easy to tell them apart from normal rear hubs. When the bike is rolling, the hub rotates without friction and the pedals can remain still (or coast), whereas when you apply backpressure to the pedals (pedal backwards) the internal braking mechanism applies friction to slow the wheel rotation down.
Coaster brakes used to be commonly found on BMX bikes, however today the use of these brakes is mainly reserved for cruiser style bikes (think big wide bars, huge saddle, cruising around LA in the sun).
The braking mechanism is similar to that of a drum brake, in the way that shoes are moved in an outward motion to create friction. Coaster brakes can be fitted to most bikes with little adaptation, although it’s important to note that there is only one sprocket on the hub, so it will be a single-speed.
The force being generated by back pedaling is rotational, so if the hub was not fixed in a set position then it would simply spin – thus highlighting the need for what is called the reaction arm. This is an external arm, which exits the non-drive side of the hub and has to be fixed in a stationary position. It is this arm that anchors the internal section of the hub, so when you pedal back you are locking the braking system against something stationary.
The main advantage of employing a coaster brake is that fact that no external controls or components are needed. Levers and cables can get in the way, as well as being vulnerable to damage. By eliminating the need for all these components, the bike becomes much more sturdy and service free, which leads onto the next advantage: apart from the initial fitting and set up, coaster brakes, as sealed units do not require much maintenance and are weather resistant.
There are also a couple of disadvantages to using coaster brakes: Firstly the inability to pedal backwards can prove awkward, especially if you are just getting on the bike. Similarly to a fixed wheel bicycle, you cannot adjust the pedals to the right position; you simply have to take off in the same position you left off. Coaster brakes can also be ‘grabby’, which can result in rear wheel locking. Although this is not the end of the world if you have good bike control, it wears through tyres very quickly, which can be costly!
The simplest way to describe rollers would be as a self-powered treadmill for a bike.
Rollers are generally made up of three rotating cylinders, aligned within a frame or structure. The distance between these cylinders can be adjusted on a slider in order to accommodate bikes of different sizes and geometries. The front drum of the roller is driven at the same speed as the rear rollers through being connected with a belt. The bike (and rider) sit on top of the rollers, and pedaling keeps the bike balanced and the cylinders spinning.
Rollers are used for indoor training. The drums rotate depending on wheel speed, and so provide you with a good level of real feedback in terms of balance and riding posture. Rollers are best used for core training, as fine adjustments made in balance and steering are constantly needed to stay spinning. Rollers are also great for perfecting pedal technique, as roller-training sessions are usually more about efficiency than power output (power training sessions are much better suited to a turbo-trainer, where output can be easily monitored).
Rollers are great, as the bike can be used on them without any adjustment or precautions, and the bike offers near road response depending on rider weight distribution.
10. Fixed gear bikes
In the following section, the braking potential and method for fixed gear bikes will be explained, but for a full guide on fixed gear cycles please refer to the relevant article.
Similarly to a coaster brake system, a fixed wheel braking system does not require any remote controls (in the form of levers or cables), as it relies purely on the rider’s feedback from the pedals. As well as the lack of controls, the system does not require any caliper or friction-creating mechanism.
When the bike is rolling with a fixed-gear, this means that the pedals will also be rotating too, regardless of whether or not any force is being transmitted through them. This interdependent relationship between the pedals rotating and the wheel spinning is what creates the potential for braking. Just as clockwise force can be exerted on the pedals to spin the rear wheel and create thrust, anticlockwise force can then be applied to counteract this thrust and create reverse forces, which slow the bike down through adding friction to the mechanism.
Put simply, pedal braking on a fixed wheel bike is essentially the exact reverse to how forward force is created, through the chain and associated cogs.
Many riders opt to use this method of braking as it is said to heighten control of the bike through the use of the legs. With fixed wheel braking, the need for conventional braking systems can be thought of as unnecessary, so in terms of aesthetics, this results in a very simple design, with clean lines and no clutter.
Braking through the use of a fixed gear mechanism can be very difficult at first, and takes lots of practice to fully master. It is very much my responsibility to say that fixed gear braking is not anywhere near as safe, practical or as powerful as more traditional set ups. This is partly due to the level of forces, but mostly down to the fact that it is only slowing the rear wheel. Also, emergency braking from high speeds with only a fixed wheel brake is nearly impossible without strain on the rider, linking back to the braking system needing to inspire the rider, rather than limit.
As with a coaster brake, this method of stopping is best used in conjunction with a front brake, so both wheels are accounted for, and the forces can be shared between tyres on the road safely, so as not to lock up or skid.