... is by measuring/feeling the outer edge of the rotors.
When the lip that develops is 1 mm or bigger, they are worn and should be replaced.
A 1 mm lip on the outside of the rotor means that there's a 1 mm lip on the inside as well and the total wear is 2 mm which is what Porsche allows.
Happy Porscheing
Pedro
Pedro Bonilla1998 Boxster 986 - 311,000+ miles:
[www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)
Racecar spelled backwards is Racecar
"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"
"If you wait, all that happens is that you get older"... Mario Andretti
"Being second is to be the first of the ones who lose" ... Ayrton Senna