Post track day brakes question

[Leg]

I did Croft ast Sunday and the brakes held up just fine. Driving home they brakes were fine too (65 miles).

Whilst they are still performing fine they are now making a humming noise (I say now, this was Tuesday, I havent used the car since). All of the diagnostics through I Drive say all is well (green).

Im gonna pop the wheels off to look at the pads, my question was are the I Drive readings reliable and what is the likely cause?

[sfbimmer13]

Originally Posted by Leg

I did Croft ast Sunday and the brakes held up just fine. Driving home they brakes were fine too (65 miles).

Whilst they are still performing fine they are now making a humming noise (I say now, this was Tuesday, I havent used the car since). All of the diagnostics through I Drive say all is well (green).

Im gonna pop the wheels off to look at the pads, my question was are the I Drive readings reliable and what is the likely cause?

after my last track day (Laguna Seca) I noticed that I melted the pads and the rotors have a lot of pad material bonded to their surfaces. I had an incredible shimmy when braking, so I replaced the rotors, pads and flushed/replaced the break fluid with Motul 600 - the check control can only tell you when your pads are worn (sensors), but does not provide any information beyond that

[skierman64]

I also got some pad transfer on my rotors after the track, the symptom being some brake shimmy. I'm going to drive it a while to see if it wears off, if it doesn't get better I'll get the rotors replaced. I did not experience any brake fade during the entire 3 day weekend.

Brake Ducts seem like the appropriate fix for this in the future. I hope someone develops them soon.

SFBimmer is correct, Idrive only measures brake pad wear, it's not going to give you any indication of problems with vibration in the brakes.

[Leg]

No vibration or shimmying, just a humming noice when braking. Wierd.

[sayemthree]

probably pad materiel/

all you with a shimmey - dont waste good rotors and throw them away. have them lathed a minimum amount and take off the pad materiel.

[rldzhao]

don't mean to thread jack, but how did your breytons hold up? or did you use OE wheels?

[lucid]

Originally Posted by sayemthree

all you with a shimmey - dont waste good rotors and throw them away. have them lathed a minimum amount and take off the pad materiel.

Turning the rotors on a lathe might not solve the shimmey problem. It might work if it is simply a matter of uneven transfer of pad material, but if parts of the rotor have gone through some kind of change in material properties due to overheating, that might go deeper than the surface and removing a tiny bit of material off the surface would not change anything.

This has happened to me twice now. The first time, it went away in a couple of weeks. The second time, things are getting a bit better after a week, but we'll see, which suggests it might be uneven pad material transfer. Would using track pads help?

[skierman64]

Originally Posted by lucid

This has happened to me twice now. The first time, it went away in a couple of weeks. The second time, things are getting a bit better after a week, but we'll see, which suggests it might be uneven pad material transfer. Would using track pads help?

I'm hoping my shimmy goes away as well.

Yes, track pads would help as they are more resistant to the heat and won't melt to the hot rotors.

[sfbimmer13]

just ordered Pagid Yellow RS 19s from Turner, since I will be in Laguna Seca for 2 days this weekend - I will post the results after I have used them.

[lucid]

Originally Posted by sfbimmer13

just ordered Pagid Yellow RS 19s from Turner, since I will be in Laguna Seca for 2 days this weekend - I will post the results after I have used them.

Great! Keep us posted please.

[Leg]

Originally Posted by rldzhao

don't mean to thread jack, but how did your breytons hold up? or did you use OE wheels?

I use the OEM 18s for track, the Breyton 19s are for road use.

[sayemthree]

Originally Posted by lucid

Turning the rotors on a lathe might not solve the shimmey problem. It might work if it is simply a matter of uneven transfer of pad material, but if parts of the rotor have gone through some kind of change in material properties due to overheating, that might go deeper than the surface and removing a tiny bit of material off the surface would not change anything.

This has happened to me twice now. The first time, it went away in a couple of weeks. The second time, things are getting a bit better after a week, but we'll see, which suggests it might be uneven pad material transfer. Would using track pads help?

track pads - for sure!!!