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I came across this on the TechWiki site. What do you think of the last part (holding the pedal down hard for 2 minutes)? I recall reading somewhere else that this can warp/damage the rotors, because you're applying all that pressure at just one point on the rotors. Here is the passage, apparently from Nick Adams:

For Standard Lotus OEM items the following recommendations came from Nick Adams (Lotus development engineer)
With new pads and discs, or just new pads fitted run the car around for 10/20 miles using the brakes gently as normal to bed the two surfaces together. Once this has been done, check the surfaces of the discs and make sure there are no signs of any scoring or damage. Assuming all looks well take the car to an appropriate piece of quiet and straight, well sighted road and perform half a dozen medium pressure stops from 50 mph down to 20 mph to warm the brakes up. Avoid more than a minute between each stop so that the temperatures do not get a chance to deteriorate too much. Once the brakes are warm and the coast is clear, perform 2 or 3 hard stops from 70mph (where local laws allow!) to 20 mph, braking as hard as you can without locking up. Do not come to a halt between each stop, do them as fast as you can to get the brakes really hot. On the third stop come to a halt and, keeping your foot on the brake, press the brake pedal down as hard as you can and hold it there for at least a couple of minutes, don't apply the handbrake. This hurts if you are doing it right! This will bed the pistons, shims and pads together and will compress the pad material, giving a hard and repeatable pedal. Once the 2 minutes have passed, release the pedal and go for a short drive, using the brakes as normal to let everything return to normal temperatures. The brakes are now fully bedded in and ready for use in anger. Recompressing the pads once every few thousand miles to the above procedure will help keep the pedal firm, especially if you don't normally use the brakes hard
 

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Not saying it wrong, just different that what I have been told.
The big difference is the stop and hold the breaks on for a couple of minutes.
different thinking is that this will allow pad material to transfer to a small spot on the rotors. (Small spot is say 1/5 of the rotor where the break pucks are pushing, not the entire radius of the rotor.) This small spot will give the feel of warped rotors because it will have a different coefficient of friction in that spot. (Again that small spot will grab hard and the other 4/5 of the rotor will just grab causing a pulse when you slow down.

Like I said, not sure mine is correct and his is wrong, or mine is wrong and his is correct.

PS: Here is what Performance Friction says on bedding in the breaks
http://www.coordsport.com/blog/2010/05/performance-friction-brakes-bedding-in-procedure/
Note step 4

Here is one more link with how to bedding in many different make and they mostly all say not to leave the breaks on after a stop.

http://www.raceshopper.com/tech.shtml#hawk_bedding
 

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re: brake pad bedding

I find this odd, especially for street brakes.

It may work, if you would not accomplish these detrimental things first:

1. Glaze and damage the stock poads from overheating.
2. Warp stock rotors from applying hot pads and holding them there.

Most stock brakes and pads are not designed for repeated 50mph stops and will overheat.

Most stock organic pds do not require bedding.

I used a similar procedure for unbedded (now most race pads are bedded ona machine) race pads to heat them up and cool down in a controlled fashion. I would nver think of applying hot pds to rotors at full stop, as it would put trmendous thermal stress on an iron rotor.

Anton
 

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-I am a brake development engineer with over 15 years of brake experience at various major OEM manufacturers.

With new pads and discs, or just new pads fitted run the car around for 10/20 miles using the brakes gently as normal to bed the two surfaces together.

-OK practice, starts to get everything squared up.

Once this has been done, check the surfaces of the discs and make sure there are no signs of any scoring or damage. Assuming all looks well take the car to an appropriate piece of quiet and straight, well sighted road and perform half a dozen medium pressure stops from 50 mph down to 20 mph to warm the brakes up. Avoid more than a minute between each stop so that the temperatures do not get a chance to deteriorate too much.

-OK, won't hurt anything and starts a transfer layer.

Once the brakes are warm and the coast is clear, perform 2 or 3 hard stops from 70mph (where local laws allow!) to 20 mph, braking as hard as you can without locking up. Do not come to a halt between each stop, do them as fast as you can to get the brakes really hot.

-OK, won't hurt anything, may increase or remove transfer layer. Not all that hot as far as a brake is concerned. May start pad first fade which will help with future friction stability and lessen future brake fade.

On the third stop come to a halt and, keeping your foot on the brake, press the brake pedal down as hard as you can and hold it there for at least a couple of minutes, don't apply the handbrake. This hurts if you are doing it right! This will bed the pistons, shims and pads together and will compress the pad material, giving a hard and repeatable pedal.

-Probably does but you run the risk of leaving a spot of material on the rotor, or even warping the rotor. I understand what is trying to be done here but expect some brake pulsation after.

Once the 2 minutes have passed, release the pedal and go for a short drive, using the brakes as normal to let everything return to normal temperatures.

-Good practice, may clean off the material you just deposited on the rotor.

-I would recommend doing everything here except the hot high pedal force hold. This would be a bit much on a passenger car but no issue for a sports car.


Sent from my Nexus 7 using AutoGuide.Com Free App
 

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-I am a brake development engineer with over 15 years of brake experience at various major OEM manufacturers.

With new pads and discs, or just new pads fitted run the car around for 10/20 miles using the brakes gently as normal to bed the two surfaces together.

-OK practice, starts to get everything squared up.

Once this has been done, check the surfaces of the discs and make sure there are no signs of any scoring or damage. Assuming all looks well take the car to an appropriate piece of quiet and straight, well sighted road and perform half a dozen medium pressure stops from 50 mph down to 20 mph to warm the brakes up. Avoid more than a minute between each stop so that the temperatures do not get a chance to deteriorate too much.

-OK, won't hurt anything and starts a transfer layer.

Once the brakes are warm and the coast is clear, perform 2 or 3 hard stops from 70mph (where local laws allow!) to 20 mph, braking as hard as you can without locking up. Do not come to a halt between each stop, do them as fast as you can to get the brakes really hot.

-OK, won't hurt anything, may increase or remove transfer layer. Not all that hot as far as a brake is concerned. May start pad first fade which will help with future friction stability and lessen future brake fade.

On the third stop come to a halt and, keeping your foot on the brake, press the brake pedal down as hard as you can and hold it there for at least a couple of minutes, don't apply the handbrake. This hurts if you are doing it right! This will bed the pistons, shims and pads together and will compress the pad material, giving a hard and repeatable pedal.

-Probably does but you run the risk of leaving a spot of material on the rotor, or even warping the rotor. I understand what is trying to be done here but expect some brake pulsation after.

Once the 2 minutes have passed, release the pedal and go for a short drive, using the brakes as normal to let everything return to normal temperatures.

-Good practice, may clean off the material you just deposited on the rotor.

-I would recommend doing everything here except the hot high pedal force hold. This would be a bit much on a passenger car but no issue for a sports car.


Sent from my Nexus 7 using AutoGuide.Com Free App

+1

Everything on there sounds right, have never done the 2 minute hold before though, never heard of any of my track buddies doing it either o_O
 

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I would never do the hold thing at the end. The whole idea is to get surfaces to match. Back in my showroom stock days, I would have a set of rotors and pads just for track days and I did not try to match them. After 1 session on the track in practice or a school, the pads were bedded and matched nicely. I'm sure that there are many methods to "perfectly" bed brake pads, but I don't believe there's any magic, perfect way.
 
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