Aluminum flanges, replaced with steel! The 2010 and newer bikes have steel ones, so years of steel with no cracks, just like the Wetheads. A little knowledge goes a long way!
I have just had the exact same issue. have done 10,000 miles on my bike no problem and when i France last week I noticed a grinding noise. All the bolts were loose... Could have been a disaster.. Replacing the disc rotor, pads and bolts now...