Last summer I started getting an occasional racket when applying my rear brake. It turned out to be my rear pad had completely worn down to nothing and it was then at the point where it was just metal on metal when touching the rear brakes.

Colour me stupid, like an idiot, I didn't have a clue about brake maintenance but I soon took the damn thing apart and found that the pad was totally gone. I might have gently applied the rear brake a half dozen times before parking it and figuring out the problem was.

I went ahead and installed new rear pads and it worked like a charm but I don't like the look of the disc as it has a wide area where the pads make contact that's thinner then the rest of the disc. The outer edges of the rear disc are sharp because the groove starts right after that, the outer edge is a bit thicker then the part of the disc where the pads make contact.

My front discs are totally flat but the rear disc has this sharp ridge and rough gouge where the pads touch. That rough area of the disc still seems pretty thick but it's kind of rough.

I'm guessing that in my stupidity, I might have damaged the rear disc by letting my pads wear down too much or is there a chance that the rear discs wear down more because they are constantly in use, much more so then the front brakes? Come to think about it, I did use the rear brake a lot a couple of years ago when I was doing lots of low speed parking lot practice, so this damage might have been done way back then.

Today, I cleaned up my brake calipers and noticed that my rear pads that only have appx. 2-3 months of usage are already worn down pretty low, maybe 50% worn. I would have thought that there would be more material left on there (they're EBC brand BTW). Maybe that's normal? Or maybe my rough rear disc is wearing down my rear pads prematurely?

I'll probably get a new rear disc installed whenever I'm due for a new rear tire.

What about you guys, does your rear disc exhibit any wear groove?

 

Yes I have had grooved discs on some of my bikes. It seems to have affected some brands over the years more than others.

As for your poor disc, I suggest you have answered your own question. The fact your pads have worn down so quickly indicates that the damage to your disc is wearing away your pads at a very fast rate. Time to take a deep breath and replace IMHO! Fit new pads as well.

 

Can you post a picture of the rotor? What I'm picturing in my head isn't good.

I've never used EBC pads on a bike before but even on my track car they will last quite a while and those are more aggressive compounds that go through way more punishment and get used up a lot faster then street pads. Not trying to start anything with this, but do you ever drag the rear brake and that's why you are going through the back brake so fast? Possibly a foot injury last summer and you are now noticing a side effect?

Next time you replace the pads and rotors make sure you bed them in properly to avoid future problems like this.

 

If you cant get the rotor turned, get a new one. It will ruin youre new pads and youll still have a funny rotor. Im not even sure if anyone turns scooter rotors. Thats how its done with trucks or cars though.

 

Your rear disc is shot, replace it ASAP. And please learn to use all your brakes in unison (front and rear). The front brakes actually do or should do 60-80% of the stopping (46 yrs riding exp here). I actually wear out front pads first, then rears. The rear brake is there to assist the front, especially in hard stops.
Personally, I also don't care for EBC pads, I use SBS metallics. Be sure to buy pads for their proper applications, rear pads are different than front.
FWIW Fastrider124