How to Fix Hydraulic Brakes on a Mountain Bike – DIY Adjust

Are the hydraulic brakes on your mountain bike malfunctioning? Want to save yourself a trip to the mechanics and fix the problem yourself? Well, in that case, we have got you covered because, in this article, we are going to be explaining the different ways how to fix hydraulic brakes on a mountain bike. Because of this, you will be able to effectively fix your brakes yourself and improve the performance of your bike.

How To Fix Hydraulic Brakes On A Mountain Bike

Let’s start with the basics of hydraulic brakes.

What are Hydraulic Brakes?

When it comes to the brakes in bikes, there are several kinds; one of these is the hydraulic brakes. As the name suggests, these brakes feature liquid that is held in a special system of pipes. These extend from the brake lever down to the pistons in the brake caliper. And so, when the lever is squeezed, it pushes the liquid down the tubes toward the pistons, the pads of which then close up around the rotor in order to stop the bike.

Many people prefer hydraulic brakes over the other kinds of brakes for their bikes. Also, most high-quality mountain bikes feature these brakes. This is because they are quite powerful yet smooth and require less force from the rider to stop the bike. Another reason why many opt for this type of brake is that you can easily maintain it yourself. This greatly reduces the need for making rounds to the mechanic every time there is a minor issue.

Reasons for Hydraulic Brakes Malfunctioning

One of the main ways the hydraulic brake of a mountain bike malfunctions is by the pads rubbing against the rotor. There are multiple reasons why this can happen. One of them is that you might have pumped the brake lever when the wheel of the bike was removed. This is because if the wheel isn’t there and the pistons can be pushed too far out if the brake is used. This can result in them displacing from their standard position to one where they might start rubbing against the rotor.

The reason these pistons displace from their position is that over time the pads are going to wear down. And so, these pistons would have to move forward to compensate for the extra space that is now there. This allows them to keep working properly. But if this occurs prematurely, then the rubbing can cause your bike to slow down, make a loud noise and damage the pads and the rotor.

Another reason why the pads and the discs can start to rub together is that the brake calipers aren’t centralized. The caliper is the part of the bike that holds the pistons that are responsible for braking. And so, if it is not properly aligned over the wheel, then it can result in uneven positioning of the disc with the pads. This then leads to the pads rubbing against the disc or the rotor. And so if you face these problems, you can try our fixes below.

Fixing Hydraulic Brakes

Firstly, we’ll focus on fixing the pistons that have been pushed too far out of their original position. For this, you need a set of pliers and a flat tool like a screwdriver or a plastic tire lever. Next, you need to remove the wheel of your bike. After this, locate the pin at the base of where the brake pads are situated. Then using the pliers to pull it out and remove the pads. Once done, using the flat tool, push the pistons back into their casing, you will notice them receding slightly.

Now you need to put the pads and the pin back in their position. And after this, all you need to do is place the tire back on the bike, and you are done! Now, if your brake is still malfunctioning, you can try to re-align the caliper over the wheel. For this, you need to first locate the mounting bolts that connect the caliper to the bike. Then, using an appropriate tool, loosen them until you are able to move the caliper.

Next, you need to squeeze the brake lever, and without releasing it, tighten the mounting bolts. This is because as the caliper is free to move, braking brings it back to its central position. Next, you need to test the wheel; if there is still rubbing, then you need to do this process again. This is because it needs a couple of tries to get the caliper perfectly centered. But if there is no rubbing, then you are all set!


Why are my hydraulic brakes not working properly?

There are multiple reasons why the hydraulic brakes on your bike might not be working properly. One of these can be that the brake caliper is not properly aligned. Because of this, the pistons might not be able to push on the rotor properly when the lever is squeezed. And so the rotor is not able to stop your bike the way it should.

How do you adjust hydraulic brakes on a bike?

To adjust hydraulic brakes on a bike, you need to centralize the brake caliper. For this, you need to first loosen the mounting bolts so that they can move. Next, you need to hold down the brake lever and, without releasing it, tighten the bolts back up. Now, test the wheel; if the pads are still rubbing against the rotor, then repeat the process. But if the wheel is moving smoothly, then you are done.

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One of the benefits of having a hydraulics brake in your mountain bike is that, along with being well-performing, it is quite easy to maintain. And so, if there is any problem, then through a few quick steps, you can easily fix it. This can not only help you save money and the time and effort of taking your bike to the mechanic. Furthermore, knowing how to fix hydraulic brakes on a bike can also come in quite handy in an emergency situation where there is no mechanic around. This is why this article provides you with the necessary knowledge that you need in order to fix hydraulic bike brakes.

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Sonia Seale loves to take her bike to the mountains near her place, the bike track has provided her the opportunity to go mountain biking since she was a child. That's where she developed a great deal of interest in cycling, no matter if it's electric or mountain bike, she's all over the place and loves to fix her own bikes along with exploring the new features coming along in the industry. That's why she's here, sharing her experience and learnings with you guys.