Cazan Racing 330mm brake disks + Ferodo DS1.11 = ruined pads

[TB Rich]

I had banding like that on one of my rear discs, I was told I must have either sticking pad/piston/sliders - it was a local garage who just had a quick look at the time. Seems to be inline with what someone said about the pistons on the Brembo's sticking perhaps?

 

[madlynx]

I highly doubt that each 2 pistons on both sides were stuck at the same time. That's completely unlikely.
Both disks and pads are damaged on both sides. I had no problems with the stock disks and EBC pads. More pictures below

 

[TB Rich]

Well just takes some corrosion to make the pad drag, and banding is symptom of that. I've tracked Pagid OE rotors before without issue on Yellowstuff pads, on a mkv 1500kg Golf. I very much think you'll be clutching at straws to try and blaim the rotor material for this. Yes it's not a super high quality curved vane affair - but in an otherwise perfectly functioning braking system they're not going to give banding in 2 track days I think you said you've done?

Brakes must be off now anyway, strip the calipers down and check.

 

[PAUL JA]

Below I'm posting response from Ferodo Racing department. It was very helpful and clarifies a lot. Any comments are very welcome!

"Thanks for your note. Sorry to hear of your issues. It's not often we see this but you had hot-banding on your rotor. This happens with the following combination of conditions:

Disc with poor thermal diffusivity + pad with low conformability (i.e. a hard pad) + (often) long draggy brake applications (you might not have seen it at your harder track where you would have braked more sharply).

These conditions means that the disc cannot get heat away from the rubbing surface quickly and gets localized into circumferential bands. This means these stripes around the disc stand proud because they are hotter (less dense and thus more voluminous). A hard pad will not conform to these ridges and thus tends to ride along the top of them. This further exacerbates the situation (the ridges get hotter and stand prouder). By the end the deformation (ridging in pads and disc is permanent)

Solutions: change your discs to ones with better thermal properties, or use a softer pad. The EBC pad is much softer. I must say it is pretty rare to see hot banding like this with DS1.11 with good quality racing discs

The copper coloured dots are bronze posts braised to the friction backplate to eliminate any possibility of pad detachment. Bronze is softer than the DS1.11 friction materials and has no other implications on performance or wear.

As a practical step it is not that your pads are ruined (I don't know about your disc) but just ridged. You might try swapping them round (put inner in outer and vice-versa and do a very complete bedding (30 applications building up pressures gradually to get everything hot). I attach an idealized procedure. That might correct the situation. But with that disc pad combination there would be no guarantee that it would not happen again."

based on that we may see the same issue when using RS29's !!!!! maybe better stick to DS2500's

 

[TB Rich]

based on that we may see the same issue when using RS29's !!!!! maybe better stick to DS2500's

Totally depends on what you're doing, Chris is doing TA yeah, so it's not continual lap after lap beating the brakes is it? So something operating in a cooler range maybe better anyway. You wouldn't stick the most aggressive high temp pad on a sprint/hillclimb car because you'll not get them in to range within the avg 1min window you're 'on it'. - You should be looking to use the correct pads for the temp range you are experiancing.

What you need to do is use the AP racing brake temp paint it. http://www.jjcraceandrally.com/rally/brake-discs-calipers/a-p-racing-temperature-paint-kit
Paint the outside edge of the disk the full width spanning 2 vanes per colour. Leave a gap of 1 vane per colour. Until you know the temp you're operating in, you're pissing in the wind basically. Or suck it and see and try a few combo's. As yet I've not had anything negative with Yellowstuff on a couple of cars and rotor sets. Bite well from cold and last well against fade. Alot of EBC haters though

 

[PAUL JA]

Totally depends on what you're doing, Chris is doing TA yeah, so it's not continual lap after lap beating the brakes is it? So something operating in a cooler range maybe better anyway. You wouldn't stick the most aggressive high temp pad on a sprint/hillclimb car because you'll not get them in to range within the avg 1min window you're 'on it'. - You should be looking to use the correct pads for the temp range you are experiancing.

What you need to do is use the AP racing brake temp paint it. http://www.jjcraceandrally.com/rally/brake-discs-calipers/a-p-racing-temperature-paint-kit
Paint the outside edge of the disk the full width spanning 2 vanes per colour. Leave a gap of 1 vane per colour. Until you know the temp you're operating in, you're pissing in the wind basically. Or suck it and see and try a few combo's. As yet I've not had anything negative with Yellowstuff on a couple of cars and rotor sets. Bite well from cold and last well against fade. Alot of EBC haters though

Yep on TA I don't think heat will be a major issue, we like the RS29's because they have terrific cold bite and work well through to super hot. We'll have to see what happens when they go in and we do the next track day

 

[TB Rich]

Yep on TA I don't think heat will be a major issue, we like the RS29's because they have terrific cold bite and work well through to super hot. We'll have to see what happens when they go in and we do the next track day

Sound good then, I'll have to check out the Pagid range in more detail when mine are next due. They have so many pad's in their range I forget which sit where in the line up, but they all generally get consistent praise. I have been toying with deviating to Carbotec XP10's mind.

 

[PAUL JA]

Sound good then, I'll have to check out the Pagid range in more detail when mine are next due. They have so many pad's in their range I forget which sit where in the line up, but they all generally get consistent praise. I have been toying with deviating to Carbotec XP10's mind.

We don't have a vast experience of pads tyep, all we discovered on the Mk1 and Mk2 Focus RS's was that DS2500's and DS3000 gave us trouble, Pagid RS14 and RS29's were fit and forget.

I'm told that Mintex F2R and F6R are worth a try

 

[madlynx]

Well just takes some corrosion to make the pad drag, and banding is symptom of that. I've tracked Pagid OE rotors before without issue on Yellowstuff pads, on a mkv 1500kg Golf. I very much think you'll be clutching at straws to try and blaim the rotor material for this. Yes it's not a super high quality curved vane affair - but in an otherwise perfectly functioning braking system they're not going to give banding in 2 track days I think you said you've done?

Brakes must be off now anyway, strip the calipers down and check.

It has been checked right away - no visible problems to report.
Yellow staff pads are not as aggressive as DS1.11.
My mechanics are all agree with Ferodo's response - major cause of the issue is heat. Inner sides are just not dissipate heat quick enough, so we've decided to try and fit some sort of cooling system for the brakes.
I know that R3 rally cars should have those. Does anybody have any pictures or drawings of such devices for the stock clio RS? I'd very much appreciate any help in this matter.

 

[TB Rich]

Madeno do a cooling kit, website seems a bit screwed at the moment but from what I can see its €565, though that seems to include installation. I would expect in kit form shipped to be a fair bit less.

 

[madlynx]

Thanks for sharing! Looks like something I might be interested in. Shame that picture is so small)

 

[Russell]

http://www.rallyshop.it/index.php?main_page=product_info&cPath=21_98_122&products_id=6489

 

[Chris_200CUP]

You can't be 1st person to fit aggressive pads with these discs?
Has as anyone used the cl 5 / 5+ with these discs? Any issues?

What at track have you driven on btw out interest?

 

[Chris_200CUP]

Also why don't contact Reyland and speak to them. Worth hearing there opinion too maybe?

 

[madlynx]

I've contacted Reyland. Had 1 response so far - no conclusions yet.

 

[leeboy]

The PF kit that I've just taken off my car looks similar to your Reyland kit in all honesty, pistons in the caliper moves freely as did the sliders, so I know I've not had a stuck on caliper. I was running CL RC6 which could be a cause, but the inside wearing on both sides of the car look extreme.

 

[john_walker74]

Was seriously considering a 330mm kit but may just stick with cheapish brembo hc discs up front as they seemed good wnough at Spa recently.

 

[madlynx]

The PF kit that I've just taken off my car looks similar to your Reyland kit in all honesty, pistons in the caliper moves freely as did the sliders, so I know I've not had a stuck on caliper. I was running CL RC6 which could be a cause, but the inside wearing on both sides of the car look extreme.

Yeap, that's just confirms my conclusion: 330mm brakes + aggressive performance pads - additional cooling = ruined insides.
Thanks for sharing the information - I'm feeling more confident now and will try to fit some additional cooling systems!

 

[Chris_200CUP]

I've checked mine this morning and Insides are fine but only run on dS2500. Have see how get on with Pagids.

 

[leeboy]

Think that I will remove the fog lights and fit some ducting down into the caliper! If I can get the photos to upload from photobucket I would happily share my findings!