Brake disk question

[Markey]

I have the S4 disks as i am doing a custom upgrade for the fronts. They are 30mm standard thickness on them it has 28mm min thickness written on them. Does that mean after 1mm has gone from each side there useless?

Thing is i have had them skimmed to 28mm anyway to fit the calipers im using just a technical metal\engineering question really.
Its not going to stop me using them as the standard ones i have now are warn at least 1.5mm and stop me with no problems and there rusted to ****.

I just wondered why they had it written on them is it also becasue there cheap copies?

 

[aragorn]

thats the manufacturers spec for minimum thickness.

Not really sure what dictates the minimum thickness though.

 

[Markey]

Thats what i was thinking ill use them until i want to replace them not because somone else tells me to

 

[jcb]

my RS4 discs have the same "guidelines" but so long as they are working and don;t have a huge lip I will expect to take them past the 1mm either side rule

 

[Markey]

Thanks for the advice I was thinking that 1mm was just a little bit less than i thought a disk could handle.