New brakes tend to squeak or make a metallic noise when engaged. This is normal and this can easily be fixed.
Different types of adjustments:
The pads will need to be sanded down a bit, or the rotor will need to be wiped off of any contamination. If you hear a noise coming from your brakes, your bike may need a brake pad adjustment. The adjustment will ensure that the pad is pressing on the rotor evenly when applied and not rubbing on the rotor when the wheel is spinning.
Both your brake pads and rotor may be contaminated and will need to be adequately cleaned. Simply using Windex will help! Considering Windex is an excellent cleaning solution, thanks to its formulation with Ammonia-D, that should do the trick! To access the brake pads, you will need to follow the instructions below, and please feel free to follow the illustrations that I have attached for better reference.
- Please loosen the bolts that mount the caliper on the drop-out bolts.
- Then loosen the bolt that mounts the brake pads.
- Once you have successfully accessed the brake pads, you will need Wet-Dry Extra Fine 200+ -Grit to sand the brake pads.
- Do not get brake pads soaked due to their organic compound.
- Using Windex, apply a few sprays on a clean & durable paper towel.
- While wearing gloves, carefully decontaminate and thoroughly wipe down the (Silver) rotor with the Windex solution.
- You may need to repeat it several times until it's clean.
If the brake pads are grabbing the rotor at an angle, this can also result in squeaking or metallic noise. To adjust:
- With a hex key, loosen the two caliper bolts on its bracket. Do not remove the caliper. The bolts are located on the top and bottom of each brake caliper.
- With the caliper loose, compress its brake lever. This will allow the caliper to grab the rotor evenly and reposition itself on the bracket.
- With the brake lever still compressed, tighten the caliper bolts.
- Once the caliper bolts are tightened, you can release the lever, and your brake caliper will now be centered.
You can also check out this video:
Feel free to stop by your local bike shop to inspect your brake systems further.