I was installing a new set of brembo oe rotors on the front of my car today and noticed a large groove in one of them. I have a track event next week and need to know if this is at all normal, for balancing purposes, or if it's just not suppose to be there. Here's the link to the pics of it. Thanks in advance.

http://www.msnusers.com/mysong...=Last

 

normal...
that is how it is balanced.