Bedding your Rotors

[MiataMike]

I got this from WilWoods website. Just for anyone not in the know heres how its done according to the engineers.

http://catalogs.wilwood.com/_pdf/_pa...PadCatalog.pdf

Pad and Rotor Bedding

Bedding is a "real conditions" heat cycle and the final step in
preparing the pads and rotors for service. All pads, even OE
stock replacement parts, will benefit from a proper bedding
cycle. All rotors, especially cast iron rotors that will be operated
at sustained high temperatures, will provide longer service life
and smoother braking when properly bedded. Bedding can be
done either in the vehicle, or on a special bedding dyno that
can realistically duplicate the torque loads, pressure, and
temperature that will be realized in the vehicle.

Rotor

Rotor Bedding

Rotor bedding is an essential element to high level
performance and durability. It is most critical with cast iron
rotors. Cast iron is extremely well suited to use as a brake rotor,
but it can be susceptible to thermal stress, distortion, and even
cracking if subjected to rapid changes in temperature when it's
new. The cracking sound that you may hear when pouring a
favorite beverage over a glass of ice is thermal shock. A proper
bedding cycle will gradually bring the rotors up to temperature
and then allow them to cool slowly and completely in order to
"season" and relieve any remaining stresses from the casting
and machining processes. With some compounds, a layer of
pad material may also be embedded onto the rotor face. It is
important that this "transfer layer" be deposited slowly and
smoothly. Otherwise, pedal pulsing and compromised friction

values can result.

Pad Bedding

The bedding process is the final "heat cure" for the pads. This
final bedding cure differs from an oven heat cure in such that
the oven heat cure does not include the pressure, torque, and
elevated surface temperatures that are necessary to properly
condition the pad for service. As it is with the rotors, new pads
must be gradually brought up to temperature and then slowly
cooled. If the pads are put into hard service right from the start,
damage from fractures or accelerated deterioration due to
extreme temperature variations between the surface and the
body of the pad can occur. Overall poor performance with the

potential for rotor damage are often the results.

Bedding Steps

Once the brake system has been tested and determined safe
to operate the vehicle, follow these steps for bedding of all pad
materials and rotors.
1. Begin with a series of 8-10 light stops from approximately
30 MPH down to 15 MPH allowing 20-30 seconds for
cooling between each stop.
2. Progress with a series of 8-10 moderate stops from around
45 MPH down to 30 MPH allowing a 20-30 second cool
down period between each stop.
3. Proceed with a series of 8-10 hard stops from 55-65 MPH
down to 25 MPH allowing 20-30 seconds of cool down time
between each stop.
4. Drive at a moderate cruising speed, with the least amount
of brake contact possible, until most of the heat has
dissipated from the brakes. Avoid sitting stopped with the
brake pedal depressed to hold the car in place during this
time. Park the vehicle and allow the brakes to cool to

ambient air temperature.

Notes:

During the bedding process, a more positive feel from the
brakes should develop. This is an indication that the bed in
process is working. If any level of brake fade is observed during
the hard stops, it may be an indication that the brakes have
been more than adequately heated. Begin cooling the brakes

with light driving and without brake contact immediately.

[Titus]

I have always wondered if new cars go through some sort of brake bedding process before delivery.

[MiataMike]

They do have a dyno for bedding brakes. Who'd of thunk it

Wilwood Dyno Bedding Service

Wilwood offers computer controlled dyno bedding on many
popular pads and rotors used in high temperature racing
applications. Contact a dealer or factory representative

for details.

[ken o]

I have always wondered if new cars go through some sort of brake bedding process before delivery.

If I test drive them they do! Drive it until you smell the brakes.

[smartmx5]

I never let my rotors go to bed with me....

[HudsonHawk]

I always take them to dinner and a movie to bed them in. Makes it much easier.

[POS Racing]

Must be important Mazda included this flier in a set of brake pads I just bought from them although Mazda called the procedure burnishing.

[gabkwong]

I noticed that every mfg has different procedures. Looks like Mazda has the most gentle procedure! I don't recall I ever seen this piece of paper in the box though!

[Dante]

The WilWood procedure is pretty much identical to the burnishing sequence I've seen on websites of other brake part manufacturers, and in the GM service manuals I've got. This is basically the procedure that my Dad taught me 10 years ago, and I've never had a car that I drive develop pulsing rotors. I had OEM pads on my Vue at 65k miles and I wore the pad all the way down to the backing plate and it started squealing metal on rotor *eek* on one side because evidently the factor didn't get it on straight or something - one side wore down faster than the other.

Brake shops always tell you to "take it easy for 50 miles and try not to sit with your foot hard on the pedal especially after coming off the highway" when you put on new brakes. They figure a light duty cycle will do fine for a bedding. It doesn't have to be perfect for most folks, they just don't want them coming back in 500 miles saying "These crap rotors you gave me are pulsing already" when it's most likely the owner driving with 2 feet and overheating the pads, then standing on the brakes at every light with maximum pressure applied after a near-panic stop at every single light in town...