Rep Power: 0

One of the discs on my front brakes has a very thin (1mm wide)
groove that is concentric to the shape of the disc.

Do I need to have the rotor refinished? Can such a groove
actually affect my brake performance? In my opinion, the
would barely change the amount of surface area with which
the pad contacts the disc.

Please advise...

 
Rep Power: 0

If you brakes feel normal and are not vibrating, no need to do anything.

 
Rep Power: 324

the groove will get worse or multiply with time and cause your brakes to squeek. you can either spend a little now and fix it or a bit more later replacing the bad rotor

 
Rep Power: 0

How much to have the rotor refinished?

 
Rep Power: 0

If you take off the rotors yourself and take them to a shop, it's around $10 per rotor. If you get a garage to do everything including dismantling and reinstalling, then anywhere from $50-$100 depending on their labor.

But like I said, if you don't feel or hear anything out of the ordinary, it may not be worth the time and money to get them resurfaced ... especially if you get them to do the entire job. I mean, you can get brand new Brembo blanks for $35-$40 each... and even lower if you search around.

Also, if the groove is very minor, you may be cutting down your rotors for no reason.

 
Rep Power: 0

I have a groove on my front left disc... you can only hear it when the car is cold and braking in reverse. I use the e-brake instead sometimes.