It's like a tornado, inside it's own metal house
Looks like you picked up a stone in your pad mate, it can happen, and screws the disc real fast.
Warranty wont save you there bud, either have to live with it, or pay for new discs.
Would recommend taking the pads out on that side and seeing if the offending item is still stuck in there too.
Sweet, thanks! I didn't really care but the thought crossed my mind, could it be a faulty factory install? I will get the dealer to check at the 1000 service.
+1 to stone
But it won't affect performance at the end of the day so don't lose sleep over it.
That should have made some horrendous noise while it was stuck in there. Surprised you didn't notice.
I got a pebble stuck in my pad when my car was a few weeks old and it was the worst noise ever.
I posted in the new members area about noise i just found was comin from my front brakes in a brand new car, and both front discs have a couple of grooves on the upper part of the discs.
Ouch, that groove doesn't look too fun . I'd agree that it looks like there was a small stone inside your brake pad and rotor. If the groove isn't super deep(it doesn't look to be) I wouldn't worry about it, as you should still be okay safety wise. Have the guys at dealer check it out, and see if they'll replace it(I double they will), but you never know without asking.
-Tyler