I see a deep groove on one of my front rotors. The groove is I would say a few mm wide and deep and spans the middle diameter of the rotor. What's the cause of this and do I need to worry about it? Would it be uneven brake pad? Or something stuck in the pad?

 

It does sound like something has embedded itself between the disc and pad though, perhaps a bit of grit.

Remove the pad and take a look.

 

S2K rotors are not very expensive. If you are concerned to the surface, just replace them.
Also, do not forget to replace the pads also. Otherwise, you will have "funny" feeling such as pulling, when braking since the thickness between the left to the right may be different.

 

Grooves in the rotor are no big deal, usually. They do not require new rotors. They do not require new pads. They do not require "turning" the rotor, which is generally a bad idea under any circumstance.

It would not be a bad idea to pull the wheel off and pull out the pads and inspect them. But probably you just hit either a hard spot on the pad or a void in the rotor casting.

Keep an eye on it, and if it becomes too much worse then you might have to rethink your options (like running a file across the pad a couple times to get rid of whatever hard spot is digging into the rotor).

 

Thank you for the awesome response. I have been reading up in the DIY section about pad replacement and such. If I pull out the pads for inspection, I'm guessing I will need to bleed the system, yeah?

P.S. I think the grooves started showing up after I tracked the car. I didn't notice it before anyway....

 

No need to bleed if you inspect/change pads and/or rotors.

 

O ok. I do need to push the caliper pistons back though, right?

 

Not if you're just putting the same pads back in.

 

Sweet. Cool. Thanks.

 

free slotted rotors.