Just through use , its the heating and cooling of the disc that causes the cracking to occur....i think!
 
Rudd - no idea I'm far from an expert lol

ibiza - I trust you just asking.

no worries..
Porka disks are cast with holes not drilled after... but they all suffer cracks often.
I refuse to supply people drilled disks and get asked very often about them. grooved are the better option in my experience.
 
DO we have any trader on here that sell discs and pads?

When I had my evo you couldnt see for traders on MLR.
I think im gonna try some performace friction as they are always good.

on another note why does everyone on here rave aboout EBC disks? They are rubbish!