Originally Posted by HAYJAM

I went to do my brakes on an 09 Cayenne base and seem to have issues with the replacement rotor which are EBC rotors. Are the rotors supposed to be friction fit? The ones that are currently on slip on and off without issue. The new ones are not going on all the way. I can see a small gap between the rotor and lug hole except where the bolt is that holds the rotor to hub it seems to pull it tight to the hub. With that, it makes it impossible to mount the caliper - The pins for the pads are hitting the rotor making it cockeyed. I went ahead and mounted the tire and sungged up the bolts then removed it. The rotor was on there tight, but still looked it could be pushed on more - At this point I still could not get the caliper back on. I have taken it back off and put the old one back on. Is this normal or the EBC rotor out of spec, perhaps?

Thanks in advance

Originally Posted by Petza914

Sounds like you have a problem with the new rotor where either the center bore diameter is incorrect ir the offset of the rotor us incorrect, or both. Usually rotors slip on without any interference and are held in place with the extra screw that goes through the rotor and into the hub. The rotors are secured for use by the lug bolts. Center bore should be 71.6mm for a press fit trying g yo take advantage of the hub-centric mounting or larger if not. If you have a digital caliper, maybe you can check the center bore spec of the new rotor. Also, while taking measurements, check the distance from the face of the rotor hat or hub to the face of the rotor and see if they're the same as the old rotor.

Originally Posted by HAYJAM

Thanks for the response. The center bore measures approx. 85mm. I think the issue is the inner dimension of the rotor that goes over the outside edges of the hub. Unfortunately I haven't found what that dimension should be as of yet. The area needed to measure is the deepest part of the rotor which I can't really reach with the calipers. I'll have to come up with a methodology of making the measurement to compare to the old one.