Watch That Manual | How to replace a disc brake rotor?
25 October 2024
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Replacing your disc brake rotors might seem daunting, but with the right tools and a clear manual, it’s a task you can easily handle yourself. Whether you need to swap out a worn rotor or upgrade to a new one, this blog will walk you through the process. We’ll cover everything from identifying your rotor type to bedding in your new brakes.
How to identify your type of disc brake rotor?
Disc brake rotors come in two main types: 6-bolt rotors and centerlock rotors. It’s important to know which type you have before you begin the replacement process.
6-bolt rotors are attached to the hub with six individual bolts while centerlock rotors are secured with a single central lock ring. There are two types of lock rings, internal spline and external spline, which require different tools for removal. Check your rotor’s diameter and type, which is usually printed on the rotor itself. You can also measure it if the information is unclear.
When to replace a disc brake rotor?
Rotors are made from steel, but they can still wear down over time. Every time you use your brakes, a tiny layer of the rotor is shaved off. Eventually, it can become too thin to deliver optimal braking power. The minimum thickness is usually indicated on the rotor itself, often around 1.6 mm. If your rotor is thinner than this, it’s time to replace it.
How to replace a 6-bolt disc brake rotor?
Replacing a 6-bolt rotor requires a bit more work but is relatively straightforward.
Loosen the bolts using your Torx T or Hex T, loosen all six bolts that attach the rotor to the hub. Some may require a bit of force. Take off the old rotor and place the new rotor on the hub, ensuring it’s aligned correctly. There’s usually an arrow indicating the rotation direction on the rotor. If not, ensure the text on the new rotor is readable from the outside.
Tighten the bolts in a star pattern, this means tightening one bolt, skipping the next, and repeating. This ensures even pressure distribution. Finally, tighten the bolts to the manufacturer’s recommended torque (usually around 6 Nm) using a torque key like our TorqueTune tool.
How to replace a centerlock disc brake rotor?
Centerlock rotors are easier to replace because they use a single lock ring. Be aware that there are rings for internal and external splines. If your rotor has an internal spline lock ring, you can use a cassette removal tool like the LockOut to remove the rotor. Because the inner diameter is the same as of your cassette. Simply slide the new rotor over the hub, the serrated edge will keep the rotor in place. Hand-tighten the center lock ring, and finish tightening with the tool. For external spline lock rings, you’ll need a tool like the BracketGrip to tighten it securely.
Breaking in your new discs
Once you’ve replaced your rotors, it’s crucial to bed them in. This process helps the new rotor surface match the brake pads and improves braking performance.
Start on a straight, flat road with minimal traffic. Ride at around 15 km/h and gently squeeze the brake lever without fully locking the brakes. Ensure the wheel keeps turning as you apply pressure. Perform this braking action a few times to bed in the rotor evenly. Once your rotors are properly bedded in, you’ll notice smoother braking and increased stopping power.
Conclusion
Replacing your disc brake rotors doesn’t have to be a challenge. With the right tools and a step-by-step approach, you can easily upgrade or replace your rotors and get back to riding in no time. Regularly check your rotor’s thickness, and don’t forget to bed in new rotors for optimal performance.