Always Stop in Time with the Right Bike Brake!

• The Requirements Bicycle Brakes Need to Fulfil
• The Current Brake Set-Up
• How Bike Brakes Work – Hydraulic vs Mechanical
• What Types of Bike Brakes Are Available?
• Rim Brakes
• Disc Brakes
• Other Types of Brakes Used – Coaster, Drum and the Like
• Which Brakes Are Used on a Road Bike?
• Which Brakes Are Used on a Mountain Bike?
• Brakes on Kids’ Bicycles
• What Are the Best Brakes for Bikes?
• Maintaining Your Brakes – Spare Parts and Recommendations Why Are My Brakes Squeaking?

Have you ever wondered why bikes have two brakes? The answer is a simple one: to ensure failsafe operation. As this is particularly important when riding in traffic, the law stipulates that a bike ridden on a public road must have two independent braking systems. In addition to acting as a dual means of life assurance, two separate brakes also mean you can choose exactly how the brakes are applied, so you can do specific manoeuvres on your MTB for example. 
There are certain things which define good brakes. One of these is the ability to apply them with the necessary precision and feel, that is to say, the bike doesn’t come to a sudden, complete stop when you touch them. A sudden stop with the front brake can result in some dangerous understeer, causing the bike to wash out and massively restricting your ability to manoeuvre it. This is a common cause of accidents in the wet and cold. Slamming the rear brake on, however, you can quickly skid – especially on loose terrain. What’s more, your brakes should be tailored to you as a rider and your riding style. A coaster brake is not recommended when doing downhill, for example. It is also important to clearly define what experts call the bite point. To make all this possible, your bike set-up also has to be right. You should be able to reach your brake levers easily, with the distance from the handlebars to the levers being suitable for your hands. Another key factor for brake performance is making sure that the brake lever doesn’t have to be pulled too much before the brakes finally kick into action. Disc brakes achieve the highest braking forces ahead of rim brakes.

All current bike brakes have the same basic set-up so that they can do what’s described in the paragraphs above. It goes as follows:

1. an actuator/control system in the form of one or two brake levers on the handlebars or a brake lever and crank
2. a mechanic or hydraulic transmission unit, often a Bowden cable with casing, a cable with hydraulic fluid or a chain for coaster brakes
3. the actual bicycle brake unit – often made up of brake calipers, but can also include hub-based systems with brake pads
4. a surface where friction is applied, e.g. the side of the rim, a brake disc or the drum housing

If the rider applies the brakes, the force is transferred to the brake unit with hardly any perceptible delay and with increased intensity. Friction is then applied as the brake pad engages the moving surface and there you have it – the bike brakes!

In Europe, the front brake is usually on the left side of the handlebars, with the rear brake on the right – if the bike doesn’t have a coaster brake. 
The rest of the world, such as Australia and Canada, follows a motorbike set-up: front brake on the right and rear brake on the left. Whilst hydraulic brakes perform better, they also require more maintenance. Mechanical bike brakes are easy to maintain and adjust without any additional tools, but don’t perform as well. You can find out more in the next chapter and under Maintaining Your Brakes – Spare Parts and Recommendations.

You press the brake lever and your bike brakes, simple. But when something goes wrong or your brakes aren’t working as well as they should, you might start to wonder: how do my brakes work?  
The best way to find this out is by getting close to the wheel and taking a closer look at the brake caliper. If you can see a wire, then your brakes are mechanical and work by way of a Bowden cable. Some old bikes may also use a rod system instead of a Bowden cable in very rare cases. If your bike has mechanical brakes, cable stoppers are usually found on the frame. If you can see a cable going from the brake lever, which may be slightly bulkier at times (reservoir), to the brake caliper, your brakes are most likely hydraulic. Hydraulic brakes have either mineral oil, brake fluid (DOT) or, in very rare cases, water as the transmission medium.  
Disc and rim brakes can be mechanical or hydraulic. Cyclocross, gravel and road bikes can also have hybrid brakes. These brakes work mechanically up until a lever on the caliper, which, in turn, triggers a hydraulic piston movement in the caliper. All other types of brakes currently available, such as coaster brakes, are mechanical. Mechanical brakes or brake levers on a road bike have a different gear ratio than those on MTBs.

Many cyclists who are still young at heart will be familiar with the (good) old types of brakes: plunger, shoe or even spoon brakes.  
These early models of front brakes were mechanical and worked via a Bowden cable or rod system, with a rubber block or metal pad pressing directly onto the tires. It was hardly possible to stop quickly and wear and tear was very high, especially on the tires.  
If you pay a visit to a transport museum and take a look at the early models of bicycles on show from the pioneering 19th century, you’ll get a glimpse of just how risky cycling used to be. At this time, there were no brakes that had been developed especially for pedal bikes. Penny farthings and, later on, many safety bicycles had fixed wheel drives, that is to say, on direct-drive penny farthings, the pedals were permanently connected to the moving front wheel. On safety bicycles (similar to the pedal bikes we ride today), the power generated through the pedals would be transferred to the fixed gear on the rear wheel via a chain drive – no backpedalling, no free-wheeling. The driven wheel worked like a fly wheel, converting the kinetic energy produced by the rider into rotational energy and, therefore, always kept going, even if the rider was no longer pressing down hard on the pedals. If they wanted to brake, they had to backpedal and go against the usual direction of rotation. It was practically impossible to brake in the event of an emergency and this resulted in major accidents.

Fortunately, these times are now behind us. But even nowadays, you don’t necessarily have to use a disc brake; rim and hub brakes can be a great, simple alternative depending on the kind of riding you’re doing. Read on the find out more about the types of brakes that are currently used and the advantages and disadvantages that come with them.

Most cyclists are familiar with rim brakes, where rubber brake pads mounted on the brake arms press onto the side of the rim. There are different versions of these depending on the type of bicycle. If you would like to find out more about rim brakes for road bikes, click here. If you’re a mountain biker and want some more information, head to the “Which brakes are used on a mountain bike?” section.

Cantilever brakes were used on older city and trekking bikes until the end of the ‘90s/beginning of the ‘00s. Later on, V-brakes became popular on the front and rear wheels, or combined with a coaster brake on the rear wheel, and are still used for beginners today. U-brakes are now only used on BMX bikes and need frames and forks kitted out with U-brake bases. Some classic touring bikes are particularly eye-catching when it comes to their braking systems. They are equipped with high-quality centre-pull brakes, for a harmonious overall look. All rim brakes are placed, on brass barrels for example, so that they slide and are mounted securely using special bases, e.g. cantilever bases, but can also be moved.

When it comes to brake levers, there is a basic difference between road bike rim brakes and MTB rim brakes. Road bikes with gears feature gear shifters and brake levers combined into one. Separate dropbar brake levers are available for single-speed bicycles. Brake levers and gear shifters are usually kept separate on MTBs 
and you can choose your braking system as there are mechanical or hydraulic rim brakes available. Hydraulic rim brakes are usually more powerful, but put stress and strain on your frame, fork, rims and more.

As mountain biking was quickly becoming more and more extreme throughout the ‘90s and particularly after the millennium, brakes had to up their performance. Due to the close connection mountain biking has to motocross, it seemed obvious to start using disc brakes, especially in downhill. The surface where the pads hit the disc is larger than with rim brakes, for example, so more friction is created. What’s more, more pressure can be generated on the surface thanks to their more rigid construction, the more favourable leverage ratios and the pistons, which are often hydraulic. At the same time, the pads apply pressure more evenly and create more friction thanks to their surface – the base material (steel, aluminium, titanium) and the actual pad made of organic materials or sintered metals. The central element, the brake disc, is normally the first thing that catches the eye when you see these kinds of brakes on a bike. This is a steel disc attached directly to the hub alongside the axis with a 6-bolt or Centerlock system. In general: the larger the disc diameter (140, 160, 180, 203, 220 mm) the more performance you can get out of your brakes.

Braking performance is also largely dependent on caliper design, which can feature two pistons, one piston plus a pad left and right or 4 pistons for maximum braking performance. Maximum braking performance can be achieved by maxing out the parameters when it comes to disc size, number of pistons and pad compound, something which is especially necessary in gravity mountain biking, e.g. for enduro or downhill, as well as for heavy eMTBs. 
The brake caliper is affixed using special frame and fork mounts – previously IS2000 and now only to post-mount or flat-mount standard. The mounts are always on the left-hand side, e.g. on the frame close to the rear wheel axis, either inside or outside the rear triangle. A hydraulic cable, or a Bowden cable for mechanical brakes, is connected to the disc brake unit. The brake levers are located on the handlebars. They are combined with the gear shifters on road bikes or come as a separate feature on MTBs and single-speed bicycles. If the brakes are hydraulic, modern levers will have a reservoir inside, creating what is known as an open system which allows for the pad to be automatically repositioned. Some e-bike brakes will have an integrated circuit breaker.  
If the rider presses a brake lever on the handlebars, either the brake fluid will be pushed from the giving towards the receiving piston, or the Bowden cable will pull on a lever on the caliper. The pistons then usually move towards the disc on both sides.

First things first: all the following brakes are mechanical and use a chain, Bowden cable or, in rare cases, a rod system. There are still many fixie fans out there today who love the direct go-stop sensation of fixed gear bikes. Fortunately, the majority act within the law and at least use an additional front wheel brake. In order to stop, fixie riders skid. They put their weight as far forward as they can or lift their rear wheel a little to minimise the friction on the wheel as much as possible and they push the pedals back against the direction of rotation with their full force.

Similar to fixies, some bikes have braking systems that work on the rear wheel by backpedalling, but the difference is that they have an extra brake inside the hub (hub brake). Furthermore, the rear wheel and sprocket disengage during braking thanks to a ratcheting mechanism. This, however, limits the space inside, for hub gear mechanisms for example. Coaster brakes, for this, and other reasons such as a low braking performance and poor ability to moderate, are often used on beginner city bikes and kids’ bikes and combined with a front rim brake. Things are a little different when it comes to kids’ bikes.. Even infants who don’t have much strength in their hands can still brake well enough by using a coaster brake. Find out more here.

Drum and roller brakes are also found time and again on city, vintage, Dutch and tandem bicycles. These are hub brakes which can be used on the front and rear wheels and, in the case of roller brakes, also with derailleur gears. Most roller brakes feature a cooling element which looks like a brake disc and has a large cover with a torque arm. Drum brakes can be recognised from their relatively large hub bodies and the fact that they have a torque arm and an operating arm on the side. 

Rim brakes with pads have been the standard on road bikes since the ‘60s and are still the most widely-used kind of brakes. These come in single-pivot or dual-pivot versions, with short or long brake arms. Replaceable brake pads are mounted onto the brake arms directly or in cartridges (pad holders). These road bike rim brakes are attached either with a central bolt or with two short threaded bolts onto the frame and fork as direct-mount brakes – the frame and fork have to be prepped for direct-mount brakes. These kinds of brakes can be either mechanical or hydraulic with dropbar brake levers or combined gear shifters and brake levers.

In terms of bicycle components, cyclocross bikes have often been ahead of the curve when it comes to dropbar bikes. And so it was these bikes that paved the way for using disc brakes on road bikes at the start of the ‘10s. Nowadays, almost all road bikes are only available with disc brakes – rim brakes are more of a rarity. Frames and forks have more torsional stiffness and are combined with quick release axles to ensure an optimal transfer of braking power. The braking systems used are lightweight 2-piston systems which have a 160 mm brake disc at the front and a 140 mm disc at the rear as standard. All hydraulic components are integrated into one combined brake lever and gear shifter in order to keep parts to a minimum. There is an urgent need for the higher braking performance achieved this way – especially in the wet – as the current gravel bike trend occasionally sees these bikes used on more challenging terrain. 
Mechanical dropbar brakes feature Bowden cables with mushroom-type guides.

Older MTBs made before the millennium usually feature a brake unit split into individual brake arms. Cantilever brakes were the standard for MTBs until well into the ‘90s (short opposite brake arms with a bridge and centre-pull mechanism). V-brakes (long parallel brake arms) came into use later on thanks to the increased leverage they offer. These are more powerful and have a simpler set-up. All MTB rim brakes have limits, however, when it comes to maximum tire width and they work less well in muddy and wet conditions. Braking power could only be improved by using specific pads. The surface where friction is applied can hardly be enlarged whilst keeping the brake pressure the same and more friction also means that the brakes will overheat faster on those long downhills. The last stage in rim brake evolution involved the move to hydraulic rim brakes, which offer more brake performance, but are rather awkward when it comes to maintenance and put too much stress and strain on the other components.

In order to minimise these problems or, in some cases, to eradicate them completely, disc brakes started to be used more and more often in MTB sport from the mid ‘90s. Disc brakes are less prone to overheating and are also able to perform highly and be well moderated on long, steep downhill runs. All modern adult-sized MTBs available from BIKE24 feature hydraulic disc brakes. 
What’s more, it is relatively easy to increase brake power with other brake pads or by using larger disc brake rotors – possible from 160 to 220 mm (frame and fork must be compatible). It is also possible to get braking system with more pistons, often for a higher price. In addition to deceleration, stability (resistance to overheating) can also be improved with large discs, special pads or a specific caliper design. In XC, lightweight 2-piston brakes usually with small discs are used, whilst in DH, a 4-piston braking system is used, usually with discs that are as large as possible (at least 203 mm front and rear). Mechanical disc brakes are rare. 
Mechanical MTB brakes feature Bowden cables with barrel-type guides.

Almost as soon as they learn to walk, our little heroes also learn how to keep their balance on two wheels, usually starting off with a balance bike when they reach 2-2.5 years of age. Most children get to grips with the basics of cycling in a short space of time and soon begin to face the challenges of day-to-day cycling together with their parents. To this end, a balance bike with an additional brake, or the option of adding one to the rear wheel, is a good choice in most cases. Once they find their bike easy to handle, they can then start learning how to use hand-operated brakes early on. The size of the brake levers and leverage ratios on kids’ bikes are specially adapted to their small hands and the small amount of strength they have. When brakes work well and are easy to reach, then nothing stands in the way of cycling fun. The brakes used on kids’ bikes are either rim brakes, in the form of V-brakes and side-pull calipers, or drum brakes.

And before mum and dad know it, their daughter or son is already riding their very own children’s bicycle – usually starting at 12", then later 16" and 20". These sizes are similar to adult bikes in terms of braking systems. They often have a front brake with a brake lever and a rear brake, which either works by backpedalling or also with a brake lever. A lot of 12" and most 16" models feature hand-operated rim brakes in the form of V-brakes. 3-5 year olds, however, often don’t have the hand strength and coordination required for these brakes. Coaster brakes are easier and more intuitive for younger riders to apply, especially when they’re just starting out, but the pedals have to be brought back into position before they can get going again as it is impossible to freewheel. These kinds of brakes also require less maintenance. For older children, two hand brakes that work independently of each other are better than one hand brake in conjunction with a coaster brake. Not all brakes are equal and this applies to kids’ bikes too – there are crucial differences in quality, for example, rigid, stable brake levers are better at transmitting the braking force, and the same goes for brake arms. Disc brakes are being used more and more often on high-quality children’s MTBs with 16, 20 and 24" wheels. With hydraulic 2-piston brakes and 160 mm discs, they provide enough brake performance for kids to conquer the real trails together with their parents.

We have put together an overview of the advantages and disadvantages of the most common bicycle brakes to help you choose the right brakes for you, or a bike which has a braking system to suit your requirements.

Conclusion: disc brakes, whether hydraulic or mechanical, offer the best price-to-performance ratio and, provided you have a modern frame and fork, they are compatible with the majority of bicycle types currently on offer. Rim brakes can be an affordable alternative for road, trekking and city bikes, but do have some limitations when it comes to performance.

Most people go through the process with their cars: main parts subject to wear and tear, such as the drive, or even more importantly, the brakes, have to be regularly checked and changed. Doing so is also highly recommended for your bike brakes too, as after all, they can save your life. You can either take your bike in for a check-up at least every 6 months, or you can take care of the maintenance yourself with our checklist. 

Brake condition checklist

1. Are all brake components present, e.g. the left and right brake levers, cables/wires and braking units? Yes → 2./No → 1. a

1. a What is your current brake set-up? Can you find out what components make up your bicycle brakes and order any missing parts via the links?

2. Are there any obvious defects/signs of wear and tear, such as split cables, heavy dirt or twisted or worn-out brake pads? Yes → 2. a/No → 3

2. a  If you have mechanical brakes, Bowden cables can often become a problem after a certain period of time. You can usually tell if this is the case if the casing is snapped or scuffed, the cable ends have become unravelled and your brakes are difficult to apply (see 4. a). A new set of brake cables will quickly remedy the situation. A recurring problem with rim brakes is that the brake pads can become twisted due to loose screws (see 3. a). You can also check to see whether your brake pads are worn – less rubber on rim brakes / not much material on the pad between the base plate and disc on disc brakes. → Swapping them is easy: you can get new brake pads here. If you have hydraulic brakes, the problem could also be that brake fluid is leaking from the ends of the cables. Please note: this kind of problem should be fixed as quickly as possible with new seals and fittings – go to a specialist workshop if in doubt!

3. Are all screws on tightly? Yes → 4./No → 3. a

3. a Tighten the screws as per the manufacturer’s instructions using the right Allen or Torx key or torque wrench and attachments. If you have disc brakes, you should also make sure you check the bolts in the 6-bolt system or the Centerlock rings.

4. When you apply the brakes, do the parts on the brake caliper move equally and smoothly, e.g. onto the rim or brake disc and back? Yes → 4./No → 4. a

4. a  If you have mechanical brakes, first check that the brake levers work properly and oil, grease or replace where necessary. Then check whether the Bowden cable slides properly. If it doesn’t, it’s best to completely change the inner cable, casing and end caps. If the brake mechanism is stiff, it often helps to disassemble your brakes, clean them, oil them (leaving the pads to one side) and then grease the joints. 
The majority of hydraulic brakes are self-lubricating, provided they are properly sealed. If nothing happens when you press a brake lever, there is either a leak – check thoroughly for leaks and visit a bike shop – or the brake doesn’t contain enough fluid. In this case, you can find a bleeding kit at BIKE24 and bleed your brakes according to the manufacturer’s instructions. If your pistons are stiff when activating and hardly ever return to their starting position, you can help them along by using the piston lubricant recommended by the manufacturer.

5. Can you feel a defined bite point? Yes → 5./No → 5. a

5. a  If your brakes are mechanical, first check the pad clearance or cable tension. If this is too low, you can usually make adjustments to the brake levers and braking unit. It is also recommended to realign your brake pads.

6. Do your wheels turn freely after braking? Yes → Move on to our brake test checklist / No → 6. a

6. a If you have disc brakes, you should first try and adjust the brake caliper. If that doesn’t help, you can then try to adjust the disc, using the appropriate tool. If you use rim brakes, check the positioning of the brake body or the set-up of the return springs on the brake arms. If it’s still catching, you could try lowering the cable tension a little. If this doesn’t help, then your wheel probably has lateral run-out and must be recentred.

Practical braking checklist

1. If you can, get your partner or a friend to help you measure your braking distance.

2. Put your safety gear on – a helmet is recommended.

3. Head to a dry road which is free from traffic.

4. Start cycling and gain some speed – until your cycling computer shows around 20-25 km/h.

5. Make an emergency stop by applying both brakes equally whilst sitting on the saddle – press the front and rear brake firmly down and get your helper to measure the distance from when you started to brake to when you actually stopped.

6. Is your braking distance around 7m? Yes → Congratulations, your brakes are working well / No → 6 a.

6. a The simplest problem to fix is if a rim, disc or pad is dirty or if the latter is glazed – you’ll normally hear squeaking too if this is the case. Firstly, get some brake cleaner and clean every carefully, making sure there is no residue left. If nothing changes, get some new brake pads. If you don’t see any significant improvements after this, then your brakes are probably too small or very outdated. If you have disc brakes, it could help to get larger brake discs and sintered brake pads with some bite. If you have rim brakes, you can sometimes see an improvement with new, more rigid brake arms or bodies.

You ride through a puddle and then need to brake at the next corner, but hold on a minute: your brakes hardly slow you down and make such a loud screeching noise that passers-by turn their heads.

Some combinations of rims or discs and brake pads are very sensitive to wet and dirt and make some nasty sound effects during quick changes between static and sliding friction. Normally, your disc or the side of your rim and pad will simply dry off during braking – this is completely normal for cyclists with rim brakes.  
However, if this doesn’t help, you should make finding out the cause your top priority, as it could be dangerous to ride around for too long in the wet if it isn’t resolved. Another reason for the squeaking sound, for both rim and disc brakes, could be the position of the pads. Realigning the caliper or changing the angle of the pads slightly could solve the problem. If this doesn’t help, then it means something isn’t right with the pads’ frictional properties. In this case, we recommend getting new pads – the old ones may be oily, worn out, glazed or hardened. It is strictly necessary to check the surrounding parts and carefully remove any oil or grease residue before putting the pads on. In addition, new disc pads should first be run in according to the manufacturer’s instructions to make sure that they reach their full brake performance.