GR Yaris Brake Judder after track day.

[raz.sofer]

Hi Everyone!
It is great to join the GR Gang .
I am currently with 7500km and really enjoying the car.
But there is one issue that is happening from the start:

I was on my first track day around 2000km and the brakes started shaking ("judder") when getting hot right afterwards.
It was fixed by resurfacing the REAR rotors and replacing brake pads to Project MU HC+ (Front and rear) with proper bed in.

I did some spirited driving and didn't have an issue until today's track day where the problem has returned, but now it is much more pronounced.

I have attached photos of the front and rear rotors.

What would you suggest to do, considering it's a daily?

 

[Michael Knight]

could be good to check if your discs are straight?
If you leave the car standing in pits after hot stint it might cause discs to deform. Its always good to move car little (0-1m) to move the brake caliber to different position in disc, to avoid heat buildup and possible deforming.

 

[TheManWithTheStick]

Are you using the handbrake after coming off track and parking the car?

If so don't, as you're just dumping all that pad and caliper heat in a single part of the disc which will warp it. Leave the handbrake off after track, but make sure you're parked on a level surface!

 

[GRFan]

What kind of brakepads are they. Temp range.

I have driven on track with original pads had no problems at all. After few laps a little cool down.

The original pads can handle some abuse!

 

[tonic]

Are you using the handbrake after coming off track and parking the car?

If so don't, as you're just dumping all that pad and caliper heat in a single part of the disc which will warp it. Leave the handbrake off after track, but make sure you're parked on a level surface!

Since the GR Yaris uses a drum setup for its parking brakes, I don't think that's an issue. However, pulling the handbrake on hot discs still doesn't seem like a good idea.

 

[raz.sofer]

could be good to check if your discs are straight?
If you leave the car standing in pits after hot stint it might cause discs to deform. Its always good to move car little (0-1m) to move the brake caliber to different position in disc, to avoid heat buildup and possible deforming.

Thanks! Always doing 2-3 cooldown laps prior to pits.

What kind of brakepads are they. Temp range.

I have driven on track with original pads had no problems at all. After few laps a little cool down.

The original pads can handle some abuse!

Project MU HC+

Since the GR Yaris uses a drum setup for its parking brakes, I don't think that's an issue. However, pulling the handbrake on hot discs still doesn't seem like a good idea.

Are you using the handbrake after coming off track and parking the car?

If so don't, as you're just dumping all that pad and caliper heat in a single part of the disc which will warp it. Leave the handbrake off after track, but make sure you're parked on a level surface!

I actually do know this from my previous car. Became a habit not to park with hand brake on track days, so this is something I do even if not really needed