Features of the disc brake system
The dimensions of the disc system rotor are as follows: 140 mm, 160,180, 185, 200 and 220. over, the larger the diameter, the more effective the braking.
At the same time, not every bike is fitted with a large disc:
- for a mountain bike, the purpose of which is to descend from hills and travel along forest paths, 160 and 180 mm will be sufficient rotor size;
- mountain bike used for freeriding, i.e. descents from slopes covered with vegetation, “prefers” discs of 180 and 185 mm;
- for mountain slopes (downhill) discs 200 and 220mm are suitable. If you want to install a rotor of the largest size, you will have to replace the old wheel with one that has the shortest spokes.
The handle in mechanical disc brakes is much simpler than in disc hydraulics, in the housing of which there is a control piston. In addition to the handle, the hydraulic brakes include a hydraulic line and a caliper. The hydraulics of the bike can be closed or with an expansion tank, needed in order to top up the oil. It is attached to the handle.
Installing hydraulic disc brakes
How to fix disc brake squeaks on a bicycle
Adjusting disc brakes on a bicycle when squeaking
Like any transport, a bicycle should have a brake (disc brakes are more preferable for many), which is responsible for stopping at the right moment. At the same time, they should, if possible, be small in size and weight. In addition, we must not forget that it is necessary to adjust disc brakes on a bicycle to the same extent as rim brakes and others, so that a squeak does not appear during braking.
Brakes on bicycles differ from automobile brakes in that they are open, so the owner often pays attention to the creak. If a squeak appears on the disc brakes, you need to eliminate its cause, which can lead to a breakdown.
Bicycles with one speed (children’s, folding, city) are equipped with a rear hub brake. If you plan to travel through mud, water, snow, it is advisable to have disc, which are disc hydraulic and disc mechanical.
In the former, the movement is transmitted to the brake mechanism by a cable, in disc hydraulics it is provided by the hydraulic system.
Why disc brakes squeal?
Brake noise is usually caused by improper lapping in combination with dirty brake surfaces. New brakes must be pre-lapped: they cannot work at full strength until some of the brake pad material has settled on the rotor and created an abrasive layer there. If the block has scratched this layer or it has been unevenly formed during the running-in process, the block cannot normally catch on the rotor surface, and begins to bounce. As a result, it makes tracks and pits on the surface of the disc, turning it into a kind of gramophone record, programmed to screech.
Eliminates disc brake squeaks when braking.
During the break-in period, the brakes do not stop working at full strength until some of the material from which the brake pad is made remains on the rotor after their contact. If the brake pad penetrates this layer or the layer is laid unevenly due to incorrect braking time intervals during the running-in process, then the pad, hitting the damaged area, begins to jump a little, then hitting the rotor many times in a short period of time. As a result, vibrations appear that create microscopic series of waves on the cyclic braking path. over, you cannot get rid of the sound simply by changing the pads, because the problem is in the disc itself. Brake pad screeching is most often caused by short break-in periods, chain lubricant or chemical bicycle cleaners that have spilled onto the brake surface.
To prevent the brakes from screeching, it is necessary to roll them in correctly with a series of abrupt stops at a sufficiently high speed. This way, the pad material remains on the braking surface of the rotor. The main thing is that the brake should be pressed sharply and with effort. Slightly applying new brakes is a great way to make them squeal.
To prevent squealing in the future, it is recommended to lubricate the chain with drops, and not with a spray. And after lubrication, wipe the chain until it is crystal clear. If you are using bicycle polish, you are guaranteed to end up on the rotors. Before riding, wipe them with brake cleaner applied to a fresh towel.
If you still can’t save the brakes, then to eliminate the squeal you will need: towels, tools for removing the disc, 100 grit sanding material, brake cleaner, gloves.
1) Remove the wheel and unscrew the rotor. Place the screws with special fixing material on the threads in a dry and clean place. They should not get any oil, grease, or anything else.
2) Clean the rotor with a prepared brake cleaner, then wipe dry with a towel. You will have to repeat the procedure at least once.
3) Work the rotor in a circle, sanding it on its surface by five to six centimeters, so that the surface remains level. Thus, process both sides of the disc.
4) Wipe the rotor with a clean towel dampened with brake cleaner.
5) It’s time for the brake pads. Spray with brake cleaner, then dry with a clean towel.
6) Install everything in reverse order.
7) It is imperative that the brakes be run in correctly! To do this, you need to make several abrupt stops at a speed of approximately 25 km / h.
The reason for the squeak in the disc system may be hidden in the pads. over, the harder the material from which they are made, the stronger the creak. To prevent this, it is necessary to adjust the disc hydraulic brakes on the bicycle, the rotors are clean. If it is scratched, the squeak becomes stronger. It also rises when the rotor is made of mild steel.
The squeak of disc brakes on a bicycle during braking occurs if there are the most rigid metallized pads. Disc brakes squeak especially on a bicycle when braking powerfully in wet weather due to the high downforce. They are therefore recommended for those who are engaged in mountain tourism and travel on rough terrain.
Wear-resistant and characterized by a long service life, the disc system seizes “tightly”, which is very important. But, this quickly breaks down the rotor, since the surface structure resembles an abrasive.
Improper positioning of pads and discs is another reason for squeaking disc brakes on a bicycle. What to do to fix it in this case? The answer is simple to remove the skew.
For what reasons can there be a whistle in the pads?
Informed means armed! Let’s start with the most common causes of brake pad problems. Poor-quality pads, namely the material from which they are made, almost always lead to problems with the system. Bad brakes quickly fail, in this case there is no point in repairing them, it is easier to replace them with new ones, of higher quality and more expensive, since in the end you will have to change not only them, but also the brake disc itself. A complete replacement of the brake system can be very expensive for you, so it is better to immediately equip your car with a good “filling”.
If the brakes creak, it means that you need to urgently diagnose their health. But not always the reason lies in the pads, perhaps they simply do not fit the brake disc. To prevent this from happening, always carefully select the parts for your car. Manufacturers themselves are also mistaken, equipping their offspring with additional elements to increase the level of operation. If you decide to replace the pads or brake disc, it is better to choose parts of the same brand as the car.
You may encounter difficulties after replacing the brakes. Whistles occur due to the fact that the elements of the system are covered with a protective layer, after a while this layer is erased, and the sounds during braking stop. In order to quickly adapt the new system, do a few hard brakes so that the protective layer is removed faster.
Discomfort can also be caused by vibration of the brakes, which is provoked by a poor-quality protective plate or its absence at all. Most often, in this situation, it is required to replace or install a protective plate between the pads and the brake disc, after which unpleasant vibrations should stop.
Please note that any brake system is equipped with a wear indicator, it is this indicator that can cause squeal when braking.
The indicator has the form of a metal plate, which at a certain mileage of the car begins to come into contact with the disc. These contacts are the cause of extraneous sounds. Even on new well-adapted pads, there may be shortcomings, they consist in the incorrect fastening of the metal protective disc. Because of this, contact between the two parts occurs prematurely.
At best, you can get rid of squeaks by cleaning. The fact is that sometimes water and air can get into the braking system, this is what causes the noise. In this situation, it will be enough to carry out a complete disassembly of the system, then process all the elements and securely install them in place.
In order to fully understand the nature of the problem, you need to understand what parts of the car can affect braking. These elements include only moving parts:
- front and rear brake pads;
- piston (or calipers);
- deformation or failure of brake discs or drums;
- unlubricated brake pedal;
- wheel play.
Of course, unpleasant noises when driving are very inconvenient, but you can cope with these troubles on your own. over, a complete replacement of the brake system is not always required. It is not worth spending money on service station services, if you have a little free time, you can easily diagnose the breakdown and eliminate it. The braking system is an important element of any car, so always remember that problems with squeaks and whistles must be responded to promptly. Responsible and conscientious attitude to the problem will help you quickly understand the root of the work.
Squeak and whistle of brakes when braking
The squeaking sound of the brakes when braking can be of a different nature, in any case it is cause for concern. Squeaking brakes are a fairly common problem among motorists that requires special attention. By following our advice, you can do without service station services and find problems yourself. Let’s try to understand the reasons for such difficulties and how to eliminate them.
Squeaks when braking a bike
In this topic, you also need to understand why disc brakes squeak on a bicycle. Squeaks can occur even if the bike is new. This is due to the fact that the abrasive layer has not yet formed on the rotor. If the rotor is damaged, then problems cannot be avoided. Cracks and scratches will always provoke unnecessary noise. Very often, the pads are not installed correctly, because of this, there are problems with braking or whistling. The reasons may also be skewed parts or their incorrect location.
How the system works
All braking systems are of the same type. The work consists in the fact that pressure in the hydraulic brake system begins to increase after the driver presses on the brake pedal. This action provokes pressure on the brake pads, which transfer pressure to the disc, which is already braking directly. Caliper pressure is inextricably linked to pedal pressure, which is why you can control the braking speed.
If you decide to purchase pads for your car, keep in mind that it is better to buy parts of the same shape as the factory ones, better even of the same brand.
Manufacturers have made sure that the car always runs silently, despite the fact that the braking system by its nature emits vibrations. To do this, manufacturers divide the area of the shoe into certain segments, and special cuts are made on the surface. But there are times when manufacturers overlook this fact. You can easily make the slits yourself. Slot parameters:
To improve the performance of the system, you can do work to round out the brake pads. To do this, slightly file the edges, after installing such parts, braking will occur more smoothly and measuredly, there will be no excess noise.
The bearing deserves special attention in this topic, which can also cause problems. These elements tend to wear out and deteriorate over time, so check their condition more often so that you can fix problems in time.
Troubleshoot bike problems
Prepare thoroughly for work, arm yourself with the following materials and tools:
- wipes for cleaning parts;
- special fluid for the treatment of brakes;
- suitable sandpaper, 200 grit is fine;
- gloves and goggles for safety.
Do not forget about the safety of your health, because during work you will be dealing with chemicals that can damage your skin or eyes. Let’s consider a step-by-step procedure for eliminating squeaks or squeaks when cycling:
- it is necessary to carefully remove the locking pin, then remove the block from the mechanism;
- detach the rotor from the wheel, carefully place it on a soft surface;
- thoroughly clean the rotor with a special processing liquid, then wipe it with a napkin;
- the brake disc needs grinding, so you must clean it from the top layer with sandpaper, make circular smooth movements so that cracks and scratches do not form on the surface;
- when processing, make sure that both parts of the brake are evenly cleaned and sanded. After thorough sanding, wipe the surface with a damp cloth or special napkin. We put an ideally clean and polished disc in a dry, clean place on a soft surface;
- brake pads also need processing, we wipe them with a special liquid;
- then we grind the same pads. When working, make sure that only the upper, thinnest layer of the surface is removed. It is necessary to grind in such a way that cracks and scratches do not form;
- carefully put the rotor in place, after putting on gloves. These precautions will keep the surface free from grease and dirt;
- we carry out the installation of the pads, then we attach the blocking pin to the required place;
- we wipe and polish the bicycle brake system.
As you can see, there is nothing complicated, you need to allocate only half an hour of time to bring the bike’s braking system to perfect condition. Prompt response to problems will help you always troubleshoot problems at the very beginning of their development. It is better to periodically inspect the brake system mechanism in order to identify malfunctions in time.
Knowing the basics of repairing the brake system, you can make adjustments of any complexity. Over time, you will gain invaluable experience that you can multiply in the future.
Squeak fixing tips
In order to eliminate squeaking, there are a number of tips for bicycle rim brakes:
- keep the rim clean. Most often it is wiped with a solvent, gasoline or white spirit. The point of rubbing is to dissolve the rubber from the worn out pads that has “stuck” to the surface of the rim, and to increase the friction force. If this does not help completely, then you need to use sandpaper with medium to fine grit and clean the rim. This will get rid of annoying sounds;
- clean the pads in a timely manner. This can be done mechanically: you can scrape with a knife, you can sandpaper.
To prevent hydraulic brakes from creaking, you need:
- control of the correct installation of the disc brake pads relative to the rotor. In addition, the surfaces of the pads themselves can also be cleaned;
- disc brakes are sensitive to rotor cleanliness. They also need to be degreased in a timely manner, especially the rear rotor due to the higher frequency of use.
How to eliminate squeaky brakes
To fix the above problem, take:
- thick napkins (nylon towel);
- brake cleaning fluid;
- sandpaper with very small fractions;
- standard set of open-end wrenches and heads;
- protective gloves
Once you have detailed the root causes of the annoying braking noise, it will be easier to spot the problem. And cleaning and prevention will allow you to forget about the problem for a long time. The main thing to remember is that the correct operation of the system allows you to ensure your own safety and save money on repairs.
How to choose pads for the V-brake system
If you dwell in a little more detail on bicycles with a pincer system, then you should talk about the choice of pads. There are two types of pads for the pincer system: disposable and cartridge.
The concept of a disposable braking system does not mean that it will only last once and be scrapped. Such a system can last for years, it all depends on the driving style and the load on the brakes. However, if the module has become unusable, it will not be possible to repair it and you need to purchase a new system.
In this regard, the cartridge system looks much more preferable. Even if it costs more than its competitor, the system can be repaired quickly and efficiently in the event of a non-critical breakdown.
Also, when choosing pads, pay attention to their size. The fact is that the wrong size will lead to rapid wear of the pads and to a loss of sensitivity during braking. Check the pads periodically for wear and cleaning. The main urge to change the pads will be the disappeared perpendicular groove on the contacting element. Remember, it’s easier to do maintenance work than buying a new part.
If the pads (consumables) have exhausted their resource, then they must be replaced:
- Let’s spin the brake machine first. You only need to work with three screws. You can just remove the wheel, but it’s better to spin the car.
- First, we unscrew the screw, which is responsible for fixing the pads. Disc mechanics may have simple tendrils. They will need to be bent and remove the rod.
- We completely remove the machine from the attachment point. Now push the brake consumables forward, but not hard, because they may fall out. Use a better hexagon.
- Now let’s look at the packaging with new consumables. And also a so-called spacer is supplied in the kit. The spacer is elastic and does not allow consumables to stick together.
- Install consumables on both sides of the spacer.
- Now notice that the brake pistons have moved forward slightly. They will need to be unclenched. The hexagon will also help with this.
- Now we put consumables in place.
- Now we fix the consumables in the machine with a long screw and immediately fix it firmly. But don’t overtighten. There is a special lubricant on the screw and it will not allow it to spin from vibration.
- We place the disc between the consumables and put the machine in its place.
- We grab it with screws, but not tightly. The machine should move slightly in a vertical plane. That is left and right.
- Now let’s look at the gap between the consumables. The work is quite delicate, but not difficult. Look at the skylight. It is important for us that there is approximately equal distance between both consumables.
- Some put a blunt utility knife blade between the consumables and the disc on both sides. Just don’t cut yourself if you use this advice. It is better to just set an equal gap and check if there is any friction by scrolling the wheel.
- Only after that, one by one, we fix the machine in its place. Make sure that the machine does not move while tightening. Check again. If it strikes a little, then it’s okay, it will get used to it. The main thing is free idling.
Reasons for squeaking disc brakes
- Damp pads;
- Incorrect position of the brake consumables relative to the rim.
- heavily soiled rim.
- Contact with grease and other chemicals on the disc.
Types of braking systems
Before more specific preventive work, let’s dwell on the types of braking systems. There are two main classes of brakes: rim and disc. Both systems have both positive and negative sides.
How To Fix Noisy Squeaking Squealing Disc Brakes On A Bike
Disc brakes are the simplest type. Basically, the braking system is a metal plate located next to the wheel hub and regulating the braking process.
The rim brakes are in close contact with the longitudinal part of the rim. After pressing, the brake axle slows down the rotation of the wheel until the bike comes to a complete or partial stop. This system has received the “popular” name. ticks. The original name comes from the principle of the squeezing device, which is similar to a pliers clamp or the letter V.
To clean the brake consumables, you need to use special chemicals. Consumables need to be treated with a chemical agent and dried.
The creak of disc brakes, due to their design, depends on the pads. Here the relationship between hardness and squeak level is exactly the same as for rim pads: the harder the material, the higher the level of squeak and even squeak. Remember to keep the rear and front disc brakes clean, especially the rotors. If they are scratched, the squeak will intensify. It is also important what steel the rotor is made of: the softer the steel, the less squeaking. If the rotors are made of hardened hardened steel, the chances of squeaking are increased.
- Metallic pads are the toughest, they do not smoke when overheated, but when braking powerfully, especially in wet weather, they can make squeaking sounds. Because they provide greater downforce, they are best used in rough terrain. Such a disc brake is useful, for example, when doing mountain hiking. They are wear-resistant and have a long service life. They are able to grab “tightly”, this is sometimes necessary. Their biggest disadvantage is that they wear out the rotor more strongly, since they are similar in structure to an abrasive material. Worn out pads look like this:
- If the pads are made from organic material, they will most likely be silent. But if they are installed on your bike, then they need to be changed more often, and it is even better to have them with you in stock. Their good feature is quick “grasping”.
- Synthetic pads. “grip” not very well, but they live long and do not wear out the rotor so much.
- Another possible reason is the non-parallel position of the discs and pads.
In addition, you can give a number of tips for driving tactics:
- if possible, predict the length of the braking distance in order to brake shorter and press the pads more intensively;
- choose only high-quality material for the pads. This also applies to disc brakes and V-breaks;
- Disc brakes usually stop squeaking after being dried. To do this, you can do two or three emergency braking. Why does the creak disappear? During a series of emergency braking, the pads become very hot and the water evaporates.
Thus, despite the differences, there are common reasons why good brakes can squeak: wet weather and winter season (then the pads are always damp), the installation of new pads and the material from which they are made.
To clean the brake consumables, you need to use special chemicals. Consumables need to be treated with a chemical agent and dried.
Preventing a squeak in the brakes
A common reason for the appearance of a squeak is the replacement of the brake system. The new system requires lapping on existing parts. For a simple break-in, hard braking at medium speed is enough. If desired, the procedure can be repeated several times. The main thing is not afraid to slow down, it will be useful for new parts to be in operation without a sparing mode.
The second point to look out for when the brakes squeak on a bike is grease and lubrication elements. Lubrication is central to the proper function of bike parts. It is necessary to ensure that the moving metal elements do not suffer from the lack of lubricant. Pass the grease can on the chassis and the third-party creak will go away. Another plus will be the high permeability of parts.
Don’t forget about simple guidelines. Keep your bike tidy and clean up dirt after one or more rides. This advice is especially helpful when driving in bad weather. For basic cleaning, it is enough to use a common solvent or gasoline mixture. After cleaning, you remove unnecessary elements, thereby increasing the contact area of the pads.
Algorithm for the correct cleaning of bicycle brakes
Let’s use a schematic (step-by-step) instruction:
- First you need to make sure that there is a squeak from the brake system.
- After isolating the problem, we proceed to dismantle the brakes.
- First of all, we unscrew the locking pin and remove the wheel.
- Then we loosen / remove the brake rotor.
- We clean the disc using a special grease or oiler (if necessary, remove heavy dirt with sandpaper).
- We are trying to achieve maximum evenness of contacting metal elements.
- Next, we wipe the disc with a napkin and perform a similar procedure with brake pads. As a result, we get 2 equal elements.
- The brake rotor is reinstalled on the wheel.
- After exposing the pads, the locking pin should be in its rightful place.
How to fix Noisy, Squeaky, or Squealing Disc Breaks on your Bike (2020)
Congratulations, the brake system has passed preventive diagnostics and is ready for full-fledged operation. In order for the system to “get used”, it is necessary to make several sharp braking at a speed of 20-25 km / h.
If grease or other substance gets on the rotor, it may creak.
To clean the rotor, you need to use various detergents, as well as sandpaper.