
If you’re a mountain biker, chances are good that you’ve had to deal with brake bleeding at some point. It’s not a fun task, but it’s necessary in order to keep your brakes working properly.
There are a few different ways to bleed mountain bike brakes, and in this article, we’ll go over the most popular methods. We’ll also give you a few tips on how to make the job a little easier. So, whether you’re new to mountain biking or you’ve been doing it for years, this is the only guide you need on how to bleed mountain bike brakes.
So, let’s get started!
What is brake bleeding?
Brake bleeding might seem like a daunting task for those who are unfamiliar with bikes, but it’s actually a fairly simple process. When brakes are first installed, they usually come with some air in the lines. This air can compress when the brakes are applied, resulting in a spongy feel. Bleeding the brakes removes this air from the system, leaving you with brakes that are more responsive and easier to control.
The first thing you’ll need to do is gather your supplies:
- A bleed kit – This is a kit that includes all of the necessary tools and supplies for bleeding your brakes. You can usually purchase one from your local bike shop or online.
- Brake fluid – Make sure you use the type of brake fluid specified by your bike manufacturer.
- Gloves – Brake fluid is nasty stuff and you don’t want it on your skin.
- Rags or paper towels – You’ll need these to clean up any spills.
Once you have your supplies, you’ll need to bleed the brakes. There are a few different ways to do this, but if you want to do it yourself, we recommend the two-person method. It’s a little more work, but it’s worth it in the end.
Method #1: Two-Person Method
Here’s how to bleed mountain bike brakes using the two-person method:
- Have one person hold the brake lever while the other loosens the bleed screw.
- Once the bleed screw is loose, have the person holding the brake lever squeeze it slowly and steadily.
- As they’re doing this, watch the brake fluid level in the reservoir. When it starts to get low, add more fluid.
- Continue until all of the air bubbles are out of the system.
- Once you’re done, close the bleed screw and test the brakes.
Method #2: The Gravity Bleed
The gravity bleed is a little simpler than the two-person method, but it does take a bit longer. Here’s how to do it:
- Start by loosening the bleed screw and letting the brake fluid flow into a container.
- Once the fluid starts flowing, hold the brake lever down and let gravity do its work.
- You may need to add more fluid to the system as you go.
- Continue until all of the air bubbles are out of the brake fluid.
- Once you’re done, close the bleed screw and test the brakes.
Method #3: The Pressure Bleed
If you have a bicycle pump or an air compressor, you can use them to bleed your mountain bike brakes. This method is called the pressure bleed, and here’s how to do it:
- Start by attaching the pump or compressor to the bleeder valve.
- Open the valve and let the air escape.
- As you’re doing this, watch the brake fluid level in the reservoir. When it starts to get low, add more fluid.
- Continue until all of the air bubbles are out of the system.
- Once you’re done, close the bleeder valve and test the brakes.
- No matter which method you choose, bleeding your mountain bike brakes is a pretty simple process. Just make sure you have everything you need before you get started, and take your time so you don’t make any mistakes.
Method #4: Using a Bleed Kit
If you don’t have any of the tools mentioned above, you can always use a bleed kit. Bleed kits usually come with everything you need to get the job done, and they’re pretty easy to use.
Here’s how to bleed your mountain bike brakes using a bleed kit:
- Start by attaching the syringe to the bleeder valve.
- Open the valve and let the air escape.
- As you’re doing this, watch the brake fluid level in the reservoir. When it starts to get low, add more fluid.
- Continue until all of the air bubbles are out of the system.
- Once you’re done, close the bleeder valve and test the brakes.
Using a bleed kit is probably the easiest way to bleed your mountain bike brakes, but it’s also the most expensive. If you don’t mind spending a little extra money, we recommend going this route.
FAQ
Why should I bleed my own MTB brakes?
It’s a good idea to bleed your own brakes for a few reasons. First, it’s a pretty simple process and anyone can do it with the right tools and supplies. Second, it’s a lot cheaper than taking your bike to a shop. And finally, it’s a great way to get to know your bike better and make sure everything is in good working order.
What are the consequences of not bleeding my brakes?
If you don’t bleed your brakes, you’ll probably notice a difference in the way they feel. The brake levers might feel spongy, and it might take more effort to stop the bike. In extreme cases, the brakes could fail entirely.
How do I know if I have air inside my brake?
If your brake levers feel spongy or you notice that it takes more effort to stop the bike, there’s a good chance you have air in your system. Another way to tell is to look at the brake fluid in the reservoir. If it’s low or empty, that’s another sign that you need to bleed your brakes.
So how did the air get in there in the first place?
There are a few ways air can get into your brake system. The most common is leaks in the system. This can happen at any point, but it’s most likely to happen at the calipers or lever. Another way air can get into the system is if you remove the brakes for any reason (like to change pads or discs). When you put the brakes back on, air can get trapped in there. Finally, if you don’t bleed your brakes regularly, air can build up over time.
How often should I bleed my mountain bike brakes?
It’s generally a good idea to bleed your brakes every few months, or at least once a year. This will help keep the system clean and free of air bubbles. If you ride in muddy or wet conditions, you may need to bleed your brakes more often.
How do I know which brake fluid to use?
There are a few different types of brake fluid, but the most common are DOT (Department of Transportation) fluids. These come in different grades, from DOT-three to DOT-five. The higher the number, the higher the boiling point of the fluid. For mountain biking, you’ll want to use a DOT-three or four fluid. DOT-five fluids are designed for racing cars and can actually damage your brake system.
Can I use mineral oil instead of brake fluid?
No, you should not use mineral oil in your brakes. Mineral oil is not compatible with DOT fluids and will damage your seals and hoses. Plus, it’s not as effective at stopping the bike.
How do you get the air out of your MTB brakes without bleeding?
There’s no surefire way to get the air out of your brakes without bleeding them. However, you can try pumping the brake levers a few times or holding them down for a few seconds. This might help move the air bubbles out of the system. If not, you’ll need to bleed the brakes to get rid of the air.
Will brakes eventually bleed themselves?
No, brakes will not bleed themselves. If you have air in your system, you’ll need to bleed the brakes to get rid of it.
There you have it! Now you know how to bleed mountain bike brakes. Just remember to take your time, use the right fluid, and don’t let air get into the system. With a little bit of care, your brakes will work like new. Thanks for reading!