[Z06] brake shake
Racer
Joined: Feb 2001
Posts: 338
Likes: 0
From: Bellingham WA
Re: brake shake (KDubb)
Just watched a speedshop special about disc brakes on tnn. Today's brake pads release a gas when working that is trapped between pad and rotor. Drilling and slots allow gas to excape. See such rotors at Ken Fichtner's under Ken's newsletter at the forum directory. :yesnod:
Le Mans Master
Joined: Aug 2000
Posts: 5,529
Likes: 1,943
From: Austin Texas
Re: brake shake (KDubb)
Yep: you got a typical problem. Go get the rotors turned or replaced.
Now if you don't want to have it happen again in just a few miles, learn to
keep you foot off of the brakes all the time the car is stopped. Physics indicates that the outside of the rotor moves faster than the insides of the rotor, therefore, the outside parts of the rotor generate more heat then the insides and (voila) the outside get hotter than the insides. Since the outside it hotter, the metal expands more, causing the rotor to assume the "oblate conical pyrimid" shape. Now once the rotor has this shape, it will cool back to its normal round shape if you don't hold onto the brakes while it is stopped. If you do maintain brake pressure while the car is stopped, you will freeze into the rotor this oblate conical pyrimid shape, and (voila) another warped rotor.
Automatic tranny cars can put the car into neutral and relax the brake, while M6 guys and galls can simply put the car between gears and relax the clutch. The tiny amounts of brake necessary to hold a car stationary on a level surface is not enough that the cooling rotor will freeze in the oblate conical pyrimid shape of the warped rotor.
So while the general could use better materials, this is really a drivers error.
Now if you don't want to have it happen again in just a few miles, learn to
keep you foot off of the brakes all the time the car is stopped. Physics indicates that the outside of the rotor moves faster than the insides of the rotor, therefore, the outside parts of the rotor generate more heat then the insides and (voila) the outside get hotter than the insides. Since the outside it hotter, the metal expands more, causing the rotor to assume the "oblate conical pyrimid" shape. Now once the rotor has this shape, it will cool back to its normal round shape if you don't hold onto the brakes while it is stopped. If you do maintain brake pressure while the car is stopped, you will freeze into the rotor this oblate conical pyrimid shape, and (voila) another warped rotor.
Automatic tranny cars can put the car into neutral and relax the brake, while M6 guys and galls can simply put the car between gears and relax the clutch. The tiny amounts of brake necessary to hold a car stationary on a level surface is not enough that the cooling rotor will freeze in the oblate conical pyrimid shape of the warped rotor.
So while the general could use better materials, this is really a drivers error.
