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Did you bed in the brakes on your 981?


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I haven't done proper bedding but the way I drive and the way CA traffic/annoying drivers are here I am pretty sure I bed my brakes at least 10x a day on the way to work.... :hilarious:
J/K
 

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Bedding Brakes - Explain Please?

I have read many posts regarding 'bedding in the brakes'
These posts explain that by doing this it deposits/transfers brake pad material on to the rotors. etc.
This doesn't make sense to me. Don't the pads constantly
'clean' the rotors by wearing them away a bit each time the brakes are used?
Wouldn't this pad material transfer be wiped away as the
car is driven leaving the rotors clean and shiny- sans 'bedding in ' pad material transfer'?
 

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Re: Bedding Brakes - Explain Please?

Bedding in the brakes does a couple of things.

One is is gets the pads very hot and helps them outgas volatile compounds in the pad material.

This outgassing can actually for a layer of vapor between the pad and rotor and the brake effectiveness is reduced.

Another risk is if the brakes are used very hard early on and gotten really hot and the car brought to a stop the pad can leave some material on the rotor.

This is why when one is bedding in the brakes one should never bring the car to a stop but instead release the brake pedal once the car's speed has dropped considerably but is still say 20mph or more. I'd rather err on the side of caution and slow to say 30mph or even 35mph rather than push my luck and bring the speed down too low.

Unfortunately if one does bring the car to a stop and the pad material ends up on the rotors starting up and using the brakes again this material deposition does not wear away and the coefficient of friction varies around the rotor. The brake then "pulses" and braking effectiveness is reduced. The only way to remove this is to machine the rotors. (One might if he's ready to spend the time use a sander to really rough up the rotor surfaces but if this doesn't work he might have to do it again. Or have the rotors machined.)

The other thing is the pad and rotor surfaces abrade some and the pad makes more complete contact with the rotor. In the case of new pads and rotors the two surfaces are generally quite flat and the contact is good.

However, in the case of when new pads are fitted to used rotors the rotor surfaces may not quite flat and the pads makes partial contact.

Bedding in helps in this regard but is no substitute for machining the rotors.
 
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