Learn the easiest way to straighten warped rotors with just two tools and two minutes.
If the disc brakes on your electric scooter are dragging, or keeping the wheel from rotating, and it’s happening once or twice per rotation, you likely have a bent brake rotor.
You’ll need a permanent marker and a small crescent wrench for this repair.
How to Fix Warped Rotors on an Electric Scooter
Total Time: 2 minutes
Place your scooter on an elevated surface, so you can spin the wheels freely.
Elevate your scooter on something sturdy like an upturned milk crate, so you can easily spin the wheels while having an eye-line straight down on the brake caliper.
If you have warped rotors, you should see them moving side to side because they are bent.
With a permanent marker, mark a guideline on the rotor to find the high and low contact points.
Bracing your hand against the brake caliper, hold the tip of a permanent marker against the rotor and spin the wheel.
Drawing a guideline will show you the high contact points (where the marker hit the rotor) and low contact points (where there’s no marks), giving you a better idea of which way you’ll need to bend the rotor.
Use a small crescent wrench on the low contact point of the rotor, and bend gently away from the tire.
Start by making slight adjustments, as you don’t want to force the rotor too hard in the other direction.
After bending the rotor, try spinning the wheel to see if you’ve straightened it enough or if it still needs some tweaks.
If you notice that the rotor is still wobbling inside the caliper, find the low point on the rotor and repeat the process of bending and spinning until the rotor is running straight.
Once you’ve straightened the rotors, make sure that the wheel spins freely.
When checking the spin, it’s okay if your brake pads are slightly touching the rotor. When repaired, the rotor should run straight when spun, rather than wiggle between the calipers.
Once you’re done adjusting, make sure that the brakes aren’t dragging, as that’ll affect overall ride quality.
For more technical guidance, speak directly to experts and enthusiasts from the scooter community in ESG Forums.