Originally Posted by KonaRider24
I think gastro's smart enough that I don't have to explain it out in full detail..
True enough.
For those that don't know and want to know the reason, the post mounts are designed to mount a caliper in the proper position for a 6" rotor. If you want to use a 7" or 8" rotor, the caliper needs to be farther from the axle to account for the larger radius of the rotor, hence the adapter.