Brakes Brake disc warping

[PaZeRa]

Howdy,
I participated in my second track day last week. Even though I cooled my car properly by doing couple of cool down laps, especially after feeling brake fade,I feel quite strong vibration during braking from high speed. Those vibrations cannot be felt during braking in city driving. No other vibrations without braking.

my discs are not discolored so they were not overheating. Also I have never felt any burnt brake pad smell.

It seems that they just warped due to medium track use. I had an instructor so there were no rookie mistakes.

Did you experience something like that? Maybe there is a different cause. Will the brakes settle after some time?

 

[Deleted member 2480]

Could be pad deposits on the discs rather than warped discs

 

[PaZeRa]

Discs looks good, like everyday use. Will post photos later

 

[PaZeRa]

@Kev_G Thisnis how they look

Disc 1
Disc 2
Mind my red reflection

 

[R Veloster N]

Apologies but discs/rotors don't ever warp. They can have a buildup of pad compound material that make them uneven, which will cause a pulsing in the brake pedal, vibration or uneven wear of the pads. They can be improperly installed and not flush to the hub. They can have some runout from not being machined correctly. They can crack under hotter temps but will not warp.

Rotors are cast at extreme heat, far beyond what a driver can produce even at sustained track speed. It would take the rotor to duplicate or surpass these extreme temps to come close to warping. They can be bent or brake from an accident but not warp. This is widely known and clarified; the term warp is not synonymous with the actual action.
Please, inform yourself thru these links;

Why Do Brake Rotors Warp? | YourMechanic Advice

Brake rotors are the large metal discs visible behind the wheels of a car. These spin along with the wheels so that when the brake pads clamp down on them, they stop the car. Brake discs have to withstand a tremendous amount of...

www.yourmechanic.com

Solved: The Mystery of Warped Brake Rotors

www.mechanic.com.au

Warped Rotors - Service Brakes: Runout, Disc Thickness

Related Articles - Top 10 Brake Mistakes - Composite Brake Rotor Service Opportunities - Power Steering Fluid Replacement Myths take hold because either A) they seem completely logical or B) they are so often repeated that they just become common knowledge. The warped rotor myth is a little bit...

www.brakeandfrontend.com

There are hundreds more but this ought to suffice.

Buy and use a brake hone to remove pad material off the rotors or have them turned properly.

 

[PaZeRa]

Thank you for that insight. Though the term warp is propably mostly referenced to actual warp after for example cooling disc down with water spray. Then I think they really warp. I understand that this is not my case.

Either way, is this normal that I have this uneven surface due to pad compound deposit after a trackday? Will this go away on its own? I

 

[R Veloster N]

Thank you for that insight. Though the term warp is probably mostly referenced to actual warp after for example cooling disc down with water spray. Then I think they really warp. I understand that this is not my case.

Either way, is this normal that I have this uneven surface due to pad compound deposit after a trackday? Will this go away on its own? I

You're welcome!

It's really an improper word used for the issues that arise with rotors. It's just a catch word which has been adopted. Actually, not even with water spray on red hot rotors. They just don't warp as the term suggests.

Generally not, if the car is used on the track more than periodically. This is why I suggested; buy and use a brake hone to remove pad material between events or under very extreme use.

Cleaning rotors with compounds, are not conducive to removal or optimal brake operation. Last thing you need to do is; compromise the rotor by embedding a compound that will reduce the necessary friction required from the pads and the rotor.

Most of what you're commenting to is; pad compound glazing, which can be removed by a brake hone or rotor turning.

If you're going to track the car more frequently I'll also suggest you invest in a different set of rotors. Slotted rotors will help reduce material build up on the rotors. You can also purchase a set of rotors fairly inexpensively for back up.

 

[PaZeRa]

Now that you inform me of the really source of the problem, I googled it and it seems that it happens even with bmw m3. People are stating that it goes away after at least 10 days of everyday driving.

Im on my vacation now. If this will not go away after doing so many km then I will have my rotors honed. There is no option for to do it by myself

 

[PaZeRa]

@R Veloster N I just wanted to note that you were 100% right and my brakes are slowly coming back to normal so its definately brake pads deposit and not warped disc

Althought it takes a long time to make it on its own so doing it with a brake hone is advisable.

BTW I had slotted rotors in my bmw e36 which I used rather lightly. I noticed that those slots are being clogged up. I started wondering if the effect really is there after putting some miles on them. Maybe I should have manually cleaned them from time to time?