Scrapes on Surface of Rim

[Jpfab5]

I recently got a used mountain bike and when I apply the rear brake, it makes a REALLY LOUD SQUEAL!!!... at first I thought it was brake residue build-up on the surface of the rim, but after cleaning all of the residue off, it still squeals.

After inspecting the rim even further, it seems like there are little grooves that have been dug into the rim of my wheel. I'm kinda hoping this isn't that big of a problem because I am a college student so I don't have much money to replace the whole wheel.

Does anybody know what caused this or how to fix it?

Thanks

[Alex Ramon]

Unfortunately it's not a good sign if there are grooves in your rim. They are caused by your brake pads wearing into the rim over time. The only way to fix it is to replace the rim.

If you upload some photos we should be able to tell you if it's critical to replace them or not. If you have to replace them, maybe you can find a good used wheel somewhere. New complete wheels are around $40 for a basic aluminum one.

[j beede]

Make sure that your brake pads have 1-2mm of toe in. I use a popsicle stick under the trailing edge of the pads as a shim to set the toe. This will cure many cases of brake squeal. This will not help ticking, clicking or knocking sounds due to brake surface damage on your rims.
...j

[marcdominic]

I have seen groves on a wheel rim caused by somebody's (mine) over zealous use of metal tyre levers! Didn't seem to severely affect the braking but there must be some effect...

[Joe_W]

Closely inspect the brake pads. There might be debris embedded in them (stones, glass shards, metal...). Maybe upgrade to other pads that are less aggressive on the rim, search the forums for other discussions on brake pads.