Hey guys.
 
When should i be replacing my rotors? If there are no noticeable cracks, what is the minimum thickness until i need them replaced. Ive read somewhere the minimum thickness is engraved into the edge of the rotor. But maybe its not the case with the DBA rotors i have. Keep in mind i have late model rotors so they will be,

• Front - 275mm x 30mm
• Rear - 281mm x 22mm

Thanks all :) 

I found this for SW20's.
Looks like -1 mm for rears and -2 mm for fronts is allowable.

My front rotors warped more than 5mm's. Not even an exaggeration. moved the calliper they were that warped

So thats when you change rotors :P

Thanks for the info, Reddtarga. Know what to keep an eye out for now :)

is there a noticeable lip near the outer edge? 
when you can't slide the caliper up because the pad fouls that lip, then you need new rotors :)