We see a lot of bikes come in with extremely worn disc brake pads. Once they get to the point of the one on the left, it is time to re up. New pads will work better and make less noise. We check every mountain bike that comes through the door as this is something you don’t want to become a problem. We’ve seen some pads worn completely to the metal, which ruins your disc. So, if you haven’t had your bike in the shop lately, take a look at you pads or bring it by for us to take a look at.
BONUS TIP: Noisy disc brakes can be very annoying. Use some rubbing alcohol on a clean strong rag and apply it your disc to quiet them down. You can also floss the rag between your pads to clean them. Make sure to never pull your lever while the wheel is off, the pistons in the caliper can be pushed to far out.