[cmv96]

I've had a new Stan's aluminum coated rotor on my front Magura disc brake now for about 2 weeks. I just put a new Stan's rotor on my rear wheel. However, the rear rotor is scraping on the inside top edge of the caliper. You can see scrape marks developing on the outside edge of the rotor. However, when I hold my finger just above the outside edge of the rotor carefully bracing my finger against the top of the caliper, it appears that the outside edge is perfectly round and true. How can this be? I'm stumped. When I put my original Magura rotor back on, the scraping noise goes away. There is no scraping on the front with my Stan's rotor. AND, when placed side by side, the new rotor appears to be exactly the same diameter as the Magura rotor. But then why doesn't my Magura rotor scrape??
Also, Stan's braking power seems to be quite a bit less than my old Magura steel rotors.

Thoughts/opinions/advice anyone??

 

[shiggy]

Your caliper hates the rotor

 

[WOY]

Thickness?

 

[cmv96]

Thickness?

Their is adequate clearance on both sides of the rotor as it passes through the caliper. Besides, it is not rubbing on the sides but rather the outside edge (think circumference)

 

[jf73]

There should be a tiny tolerance between the size of the rotor bolt holes in the rotor and the rotor bolts themselves. If you do not get the rotor bolts somewhat centered in the holes of the rotor it can cause this, but normally you only get rubbing on the top of the disc at one point as it rotates..

 

[cmv96]

There should be a tiny tolerance between the size of the rotor bolt holes in the rotor and the rotor bolts themselves. If you do not get the rotor bolts somewhat centered in the holes of the rotor it can cause this, but normally you only get rubbing on the top of the disc at one point as it rotates..

Good point, although I'm using the DT Swiss centerlock adapters to hold the rotor in place: http://www.mbaction.com/detail.asp?id=1163