Solid rotors have no place for the air in the holes to go. So the air is trying to push the pads away from the rotor. Thus the noise. Vented rotors let the air go thru the holes, and thru the middle of the rotor, then out the outside diameter. No pushing out of the pads.

Tom

"Everyone should believe in something; I believe I'll go fishing."

-Henry David Thoreau

Men and fish are alike. They both get into trouble when they open their mouths

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