Even in the rain, the stopping power of disc brakes on the road is consistent and reliable. This is why almost all cyclists who try disc brakes eventually give up on rims brakes.
Disc brakes are quite reliable, but they can produce a lot of noise if they are not adjusted or serviced properly. The cacophony of disc brake noise may be enough to ruin a group ride or break you out of your zone while riding alone, whether it be a ‘pinging’ with every spin of the wheel or a roaring shriek when braking.
When using disc brakes, it is usual to hear a slight noise now and then. If you are caught in the rain or ride through a puddle, you may anticipate a certain amount of noise. The majority of the time, the brakes will quiet down on their own. On the other hand, if you take your vehicle out on a few dry rides and the squeaking still persists, you may have contaminated brake pads or rotors.
Pinging noises are another common disc braking noise after a lengthy downhill journey. Disc brake manufacturers may give you different answers on the origin of the pinging. The pinging sounds are generated by thermal distortion of the rotors, according to Shimano’s public relations representative Dylan Stucki. The same can be said about Brooklyn Fowler, the Technical Marketing Manager at SRAM. They said it was due to “a brief thermal distortion of the rotor” that corrected itself as the rotor cooled down.
When disc brakes are properly adjusted, they should make just a faint, fleeting noise. The system will cool down and become quiet once more after a brief period of time over flatter ground. But if this happens frequently or the noise lasts for minutes rather than seconds, it’s a warning that your brakes need to be serviced.
If your disc brakes are making noises beyond the typical pings and tings, you may take these measures to determine the cause and get them fixed.
Issues with Caliper Alignment and Their Resolution
The rotor rubbing against the brake caliper is a prominent source of disc brake noise. Whether or not the rotor is centered between the pads may be easily seen by peering into the brake caliper. To hear squealing and feel brake rub, check to see whether the rotor is out of alignment to the point that it is making consistent contact with one of the pads.
Increased noise might result from heat deformation during braking and even frame flex if the rotor and caliper are even marginally misaligned. Tolerances on road disc braking systems are quite tight, therefore having perfect alignment is essential.
Instructions for Installing a Mechanical Disc Brake
If your bike has mechanical disc brakes, you should check to see if the brakes apply pressure to the pads on both sides or just one. Squeezing the brakes and seeing inside the caliper (much as when checking rotor alignment) is the quickest and most accurate technique to see if they are properly aligned. If the pads close in on the rotor at the same time, you should try to keep the rotor in the middle of the disc.
Rotor alignment differs somewhat depending on which pad shifts (in mechanical systems). Aim to move the caliper till the fixed brake pad is as near to the rotor as feasible without generating any noise or rubbing. So, when you use the brakes, both pads will make complete, uniform contact with the rotor.
If the brake pads on your disc brakes get contaminated, you will hear a squealing noise. It’s not good for your brake pads if you ride through oil on the roads or if you get any kind of degreaser or lubricant on them by mistake.
Cover the disc rotor and caliper before washing your bike, or spray the degreaser on the chain in a way that prevents it from getting onto the rotor.
As long as the wind isn’t blowing in the direction of the rotor, you may spray degreaser on the chain where it connects to the crankset under the driveside chainstay. It is recommended that you use a disc brake cleaner made specifically for this purpose, or isopropyl alcohol, whenever cleaning disc brakes.
The possibility of pad contamination can be reduced significantly by using a chain-cleaning equipment.
If your brake pads are contaminated, you will hear a screaming sound when you stop, and you will have much less stopping power.
The simplest solution is to change the pads and clean the disc rotor and brake caliper thoroughly.
It is possible to sand away part of the pad material or burn off the impurities using a blow torch if there is a significant amount of pad material remaining. While sometimes effective, this strategy typically causes more headaches than it’s worth.
The disc brakes have not been properly bedded in.
Disc brakes may be a source of annoying noise and vibration if they aren’t properly bedded in.
When you get a new bike or put new pads on, you need to let the disc brakes bed in. A portion of the pad’s material is transferred to the rotor during this procedure, resulting in improved’mating’ between the two parts and less noise-making vibrations.
Find a quiet spot to ride in your disc brake pads, and then gradually slow down until you are virtually at a stop, applying even pressure to both brakes. Then, after ten or fifteen repetitions, let go of the brakes. As you move through the sequence, you’ll notice an improvement in stopping power.
When breaking in disc brakes, gentle pressure on the brake levers is required. Because of this, the brake won’t be able to keep the wheel from spinning, and the material won’t be transported from the pad to the rotor in a uniform fashion.
A bent rotor might be the culprit.
Brake rub may still exist even after caliper alignment, suggesting a bent rotor is to blame. If you lean your bike against anything and don’t notice that the rotor is touching the surface, you’ll likely experience this problem. Rotor bendage is another simple risk while transporting a bike in a car. Although the tiny discs of metal are constructed out of steel, they were not built to withstand asymmetrical forces.
The process of repairing a rotor that has been bent requires thorough and painstaking investigation to pinpoint the precise location of the damage. The simplest approach to check for noise is to carefully rotate the rotor inside the braking caliper. You can tell which pad the rotor is pushing against within the caliper. The wheel must be turned counterclockwise until the crooked spoke is clear of the brake. Then, you should use a rotor truing tool to reposition it such that it no longer contacts the caliper. Avoid applying too much pressure, since doing so might cause the rotor to bend in the other way.
Worn pads might cause unwanted noise to emanate from your skateboard.
The sound of metal on metal can be heard if the brake pads have worn down to the rotor of the disc.
There is usually a way to tell how much pad material is remaining by looking at the back of the brake caliper or by removing the wheel and inspecting the pads directly.
There is a clear sign of wear on Campagnolo disc brake pads. They also have an audio alarm when they are about to be hit.
The disc rotor and caliper must be meticulously cleaned prior to installing new disc brake pads to prevent any pollutants from migrating to the new pads and to facilitate the finest bed-in procedure.
Inadequate or excessive bleeding
Overfilling the brake fluid during bleeding can force the caliper pistons to advance farther, decreasing the amount of space between the pads and rotor and increasing the risk of rubbing.
Using a piston press or a plastic tyre lever to force the pistons back into the caliper bores should reveal the problem. You won’t be able to properly press the pistons back into the caliper bores if the fluid has been overfilled.
If you want to avoid this problem, make sure you utilize the right caliper spacers while bleeding your brakes.
Not Your Brakes, Maybe Your Frame Is at Fault
If you’ve exhausted these options without success, it may be time to examine your physical structure. The frame mounts (to which the caliper connects) must be properly prepared to ensure that the caliper, pad, and rotor sit nice and square while altering the alignment.
Usually, manufacturers will do this before sending it out to stores. When finishing, the mounts didn’t always get all of the surplus material removed, and the brake mounts weren’t always correctly masked. Sometimes it might be due to sloppy tolerances in production.
Get your bike to a store that sells disc brake-facing tools, since this is the most reliable method of fixing the problem. It’s safe to assume that most stores offer this service, but it never hurts to ask! To verify that your calipers are sitting flat and square to the rotors, you may use this tool to remove any extra material from the mount.
Keep in mind, however, that some background noise is unavoidable…
Sadly, our world is far from ideal. Though you ride through water, grit, or dirt and some of it makes its way onto your brake pads, you may still hear some noise even if your brakes are properly aligned.
Disc brakes for road bikes have substantially tighter tolerances than those used on mountain bikes. The room for error is much less, and despite your best efforts, you may still hear some background noise sometimes.