Eli5: Why do bicycle disk breaks have “%” and “V”s stamped through them. Is this the most efficient way of displacing heat / reducing cost ( materials ) or does it just look cool?

Question

Eli5: Why do bicycle disk breaks have “%” and “V”s stamped through them. Is this the most efficient way of displacing heat / reducing cost ( materials ) or does it just look cool?

In: Engineering

Answer 1

Mechanical engineer here. Similar to the design in many circular saws, they are for “absorbing “ thermal expansion when the rotor heats up thereby preventing warping.