50% of the cost of the bicycle featured in this video was donated by JensonUSA.

In this tutorial we will learn how to straighten a bent disc brake rotor.

What You’ll Need

For this job you will need a zip tie and wire cutters, and a disc truing tool or an adjustable wrench for straightening the disc.

Makeshift Gauge

The first step is to fasten a zip tie around the frame or fork, and cut the end about 1 cm away so that it lines up close to the disc. Position the cut end of the zip tie close to the disc so you can use it as a makeshift gauge and easily tell where and by how much the disc is bent.

Straightening

Using your truing tool or adjustable wrench carefully bend the disc a little bit at a time. Be careful not to bend it too much either way. Rotate the disc to check for true and then repeat as needed until the disc is as straight as possible. You likely won’t be able to get the disc perfectly straight, but using this method it should still be ridable. If the disc is too bent it’ll need replacing.

• Bicycle Torque Specifications

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