how do you bed-in brakes

Discussion in 'The whoa and the sway.' started by 12lives, Dec 27, 2019.

  1. 12lives

    12lives Control the controllable, let the rest go

    In the last several years I started to bed in my new brake pads when I change them. I loosely follow the guidance from tire rack, baer, etc. I have a back road nearby where I can get up to speed for a short distance and never have to stop the car until I get home. I notice in some of my cars that used to have squeaky brakes that the issue has gone, I get better feeling brakes, shorter stopping distance, etc. But if you don't have that back road, what do you guys do? or do you?
     
  2. telriv

    telriv Founders Club Member

    I have always used the 30-30-30 rule. 30 stops from 30MPH with a 30 second cool down in between. Always appeared to work for me.
     
    Footbag likes this.
  3. sean Buick 76

    sean Buick 76 Buick Nut

    Yes I do the same
     
  4. StfSocal

    StfSocal Well-Known Member

    I've always done the following:
    5 aggressive stops from 40-10 (rapid succession, no cooling time)
    5 moderate stops from 35 to 5 (rapid succession, no cooling time)
    Then I drive around for 10 minutes without stopping to allow the brakes to cool. Luckily my neighborhood is a giant 2 mile circle w/ no stop signs so I coast around for a couple laps at about 20-25.

    I've done this on all my cars, trucks, and motorcycles (a little deviations but same process). Always had great brake operation after doing this. The first time i ever did brakes (17 years old) i just put them on and then drove normal. Brakes were horribly under-powered and noisy. After about 2k-3k miles I swapped out the pads and resurfaced the rotors. I then learned about bedding brakes and it made a world of difference.
     
    Dr. Evil likes this.
  5. StfSocal

    StfSocal Well-Known Member

    Oh and I usually bleed the system at the same time.
     
  6. Dr. Evil

    Dr. Evil Silver Level contributor

    I do a similar procedure to what StfSocal said.
    3 or 4 panic stops from about 50 mph with no cool down in between to heat them up. If possible, I try to do one in reverse also.
    Then drive around for a few minutes to let them cool before parking.
     
    GS464 likes this.
  7. Electra Bob

    Electra Bob Well-Known Member

    I used the Wilwood procedure. Front disk rear drum.

    If you are doing this on regular roads like I did be *very* aware of other traffic. I was on a remote country road and got absorbed in the repeat process and forgot to check behind on one hard stop... thankfully the guy behind me also had good brakes and reflexes.

    https://www.wilwood.com/techtip/techpadbedtip

    MINIMUM TEST PROCEDURE
    WARNING: DO NOT DRIVE ON UNTESTED BRAKES. BRAKES MUST BE TESTED AFTER INSTALLATION OR MAINTENANCE

    • Make sure pedal is firm: Hold firm pressure on pedal for several minutes, it should remain in position without sinking. If pedal sinks toward floor, check system for fluid leaks. DO NOT drive vehicle if pedal does not stay firm or can be pushed to the floor with normal pressure.
    • At very low speed (2-5 mph) apply brakes hard several times while turning steering from full left to full right, repeat several times. Remove the wheels and check that components are not touching, rubbing, or leaking.
    • Carefully examine all brake components, brake lines, and fittings for leaks and interference.
    • Make sure there is no interference with wheels or suspension components.
    • Drive vehicle at low speed (15-20 mph) making moderate and hard stops. Brakes should feel normal and positive. Again check for leaks and interference.
    • Always test vehicle in a safe place where there is no danger to (or from) other people or vehicles.
    • Always wear seat belts and make use of all safety equipment.
    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 the bedding of all new pad materials. These procedures should only be performed on a race track, or other safe location where you can safely and legally obtains speeds up to 65 MPH, while also being able to rapidly decelerate.
    • Begin with a series of light decelerations to gradually build some heat in the brakes. Use an on-and-off the pedal technique by applying the brakes for 3-5 seconds, and then allow them to fully release for a period roughly twice as long as the deceleration cycle. If you use a 5 count during the deceleration interval, use a 10 count during the release to allow the heat to sink into the pads & rotors.
    • After several cycles of light stops to begin warming the brakes, proceed with a series of medium to firm deceleration stops to continue raising the temperature level in the brakes.
    • Finish the bedding cycle with a series of 8-10 hard decelerations from 55-65 MPH down to 25 MPH while allowing a proportionate release and heat-sinking interval between each stop. The pads should now be providing positive and consistent response.
    • If any amount of brake fade is observed during the bed-in cycle, immediately begin the cool down cycle.
    • 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.
    Competition Vehicles
    • If your race car is equipped with brake cooling ducts, blocking them will allow the pads and rotors to warm up quicker and speed up the bedding process.
    • Temperature indicating paint on the rotor and pad edges can provide valuable data regarding observed temperatures during the bedding process and subsequent on-track sessions. This information can be highly beneficial when evaluating pad compounds and cooling efficiencies.
    Post-Bedding Inspection – All Vehicles
    • After the bedding cycle, the rotors should exhibit a uniformly burnished finish across the entire contact face. Any surface irregularities that appear as smearing or splotching on the rotor faces can be an indication that the brakes were brought up to temperature too quickly during the bedding cycle. If the smear doesn’t blend away after the next run-in cycle, or if chatter under braking results, sanding or resurfacing the rotors will be required to restore a uniform surface for pad contact.

    Pre-Race Warm Up
    • Always make every effort to get heat into the brakes prior to each event. Use an on-and-off the pedal practice to warm the brakes during the trip to the staging zone, during parade laps before the flag drops, and every other opportunity in an effort to build heat in the pads and rotors. This will help to ensure best consistency, performance, and durability from your brakes.
    Dyno Bedded Competition Pads and Rotors
    • Getting track time for a proper pad and rotor bedding session can be difficult. Wilwood offers factory dyno-bedded pads and rotors on many of our popular competition pads and Spec 37 GT series rotors. Dyno-bedded parts are ready to race on their first warm up cycle. This can save valuable time and effort when on-track time is either too valuable or not available at all, Dyno-bedding assures that your pads and rotors have been properly run-in and are ready to go. Contact your dealer or the factory for more information on Wilwood Dyno-Bedding services.

    NOTE
    NEVER allow the contact surfaces of the pads or rotors to be contaminated with brake fluid. Always use a catch bottle with a hose to prevent fluid spill during all brake bleeding procedures.
     
    RoseBud68 and DasRottweiler like this.
  8. BennyK81

    BennyK81 Well-Known Member

    if it's your own car...do a couple of moderate to more aggressive stops until the pedal does not feel soft anymore...then drive around...

    it really depends a lot on the condition of the rotor...if it's new it takes less time compared to a used rotor
     
  9. TORQUED455

    TORQUED455 Well-Known Member

    It all depends on the type of brakes you are using and what the pad and rotor manufacture recommend. If you are using any type of polymer-coated rotor, where the brake pads “clean-off” the coating, you will end up with all sorts of problems if you perform any type of aggressive stopping! In 2018, when we switched over to predominantly “coated rotors”, we had all sorts of comebacks for brake pedal pulsation. What we finally figured out was to adhere strictly to a service bulletin put out by Raybestos which stated NOT to do any aggressive stops, and not to come to a complete stop which burnishing in the pads. So we have a test-loop that we found that we could road test 7 miles, incorporating several sweeping curves that we have to slow down on, and finally coming back to the shop for the final, gentle complete stop. After a cool down period of a couple of hours, the vehicle is ready to go.

    Again, high-performance brakes, non-coated rotors, etc are completely different. What works with one type of braking components will not necessarily work with another.

    After dozens of comebacks, and going away from coated-rotors, we tried the coated rotors again because they certainly help in the rust-belt for daily drivers. Using the new break-in procedure and test loop, comebacks are back down to isolated and few and far between with the coated rotors.
     
    Mark Demko and Electra man like this.

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