Fixed vs. Floating Rotor Systems
Floating Discs
All metals "grow" when heated. The diameter of cast iron brake discs can increase as much as 2mm (0.080 inch) at elevated braking temperatures. When the disc is radially restrained from growing (as in all one-piece discs) the friction plates are forced into a cone shape as temperature increases, adversely effecting both temperature and pressure distribution within the pads and the feel of the pedal. The StopTech racing and high performance street discs are mounted on separate billet aluminum hats or bells. The fastening system is designed to allow radial growth and minimal axial float resulting in a mechanically stable system. All StopTech hats up to 355mm are made from billet 7075 T-6 Aluminum.
The following shows a comparison between a fixed rotor system and StopTech Floating Rotor System.
Fixed Rotor System
Rotor with Fixed Hat
Fixed hat drive pin and hardware closeup
StopTech Floating Rotor System
StopTech 2 piece AeroRotor (cutaway) and StopTech Directional Hat
StopTech drive pin installation close up
StopTech Drive pin position detail
StopTech® and Brembo® anti-rattle systems displayed