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Tor · 06-30-2016, 04:48 PM

Can someone ( @JRitt I would be grateful) please help me find the cause of this problem. Respectively give suggestion for ways to solve it?

Equipment:
Yokohama AD08R, Stock rotors, Stainless steel brake lines, Castrol SRF fluid, Porsche lower control arm brake cooling vanes and CL Brakes RC5+ pads.

Situation:
3x 1 hour stints at Zolder Circuit, with 1 hour breaks in between.
A round is a bit above 2 minutes and has 7 hard braking points. This is what a round looks like (sorry in kph and unreliable speeds because of using iPhone GPS for Harry's Laptimer, still it should give an idea:
[ame="http://www.youtube.com/watch?v=H-0tS8JGzdU"]http://www.youtube.com/watch?v=H-0tS8JGzdU[/ame]

Result:
Pads after:
Worn down 5 mm, parts breaking off:

Heavy pad deposits on the rotors:

Pads before: (One trackday 1 1/2 hours, but with Pirelli P Zero Nero GT and more cool down laps due to lack of oil cooler and before I switched to Castrol SRF.)

And the rotors after those 1 1/2 hours, also slight build up, that when away after some days of street use:

This is not an RC5+ pad bashing. I was extremly pleased with them before AND during the event. They performed flawlessly, great stopping power, no fading, great feel etc. In fact I didn't notice when driving home either. Not until I wanted to drive the car 3 days later did I notice that the brakes felt weird (mushy) and it took a lot of effort to stop the car.

Since I took them off, I have cleaned the pads and put them back in. I have driven the car again (carefully and as test) and the deposits are lessening after some harder stops, they feel better and the stopping power has improved significantly again. Obviously they need to be replaced.

What next:
I guess it would be fair to assume it's a heat problem. I wonder why I didn't feel the deterioration during the event or at least on the way home?

I would really like to get CL Brakes pads again.

Is there a weak link here that I can fix, e.g. exchange the stock rotors? Could they be the culprit? Not dissipating the heat fast enough? Would the RC5+ work better with grooved rotors?

Is the 5 mm wear normal for 3 hours? Or is this a chain reaction causing increased wear once it went haywire? I assume some of the missing 5 mm are spread across the rotors now and that wear rate isn't normal?

I consider RC6, but read they can cause sparks that damage paintwork. Also I've seen videos where they make horrible noise for street driving (the RC5+ are delightfully quiet). I also consider the RC6E but read they make a lot of dust that cake up (the RC5+ were very low dust). I use the car for spirited Sunday drives, track and occasionally daily when the weather is nice.

Basically I would prefer to stay with the RC5+ what can I do that doesn't cost a fortune to rectify this? (No major cooling mods, that I would rather put forward to the Sprint kit eventually). Would a swap to other rotors helps? Are there anything obvious in driving technique that would cause this, that I can change?

06-30-2016, 04:48 PM	#1
Tor Senior Member Join Date: Feb 2015 Drives: Toyota GT86 Location: Europe Posts: 919 Thanks: 369 Thanked 554 Times in 301 Posts Mentioned: 40 Post(s) Tagged: 2 Thread(s)	Brake pad problem (CL Brakes RC5+) Can someone ( @JRitt I would be grateful) please help me find the cause of this problem. Respectively give suggestion for ways to solve it? Equipment: Yokohama AD08R, Stock rotors, Stainless steel brake lines, Castrol SRF fluid, Porsche lower control arm brake cooling vanes and CL Brakes RC5+ pads. Situation: 3x 1 hour stints at Zolder Circuit, with 1 hour breaks in between. A round is a bit above 2 minutes and has 7 hard braking points. This is what a round looks like (sorry in kph and unreliable speeds because of using iPhone GPS for Harry's Laptimer, still it should give an idea: [ame="http://www.youtube.com/watch?v=H-0tS8JGzdU"]http://www.youtube.com/watch?v=H-0tS8JGzdU[/ame] Result: Pads after: Worn down 5 mm, parts breaking off: Heavy pad deposits on the rotors: Pads before: (One trackday 1 1/2 hours, but with Pirelli P Zero Nero GT and more cool down laps due to lack of oil cooler and before I switched to Castrol SRF.) And the rotors after those 1 1/2 hours, also slight build up, that when away after some days of street use: *This is not an RC5+ pad bashing. I was extremly pleased with them before AND during* the event.** They performed flawlessly, great stopping power, no fading, great feel etc. In fact I didn't notice when driving home either. Not until I wanted to drive the car 3 days later did I notice that the brakes felt weird (mushy) and it took a lot of effort to stop the car. Since I took them off, I have cleaned the pads and put them back in. I have driven the car again (carefully and as test) and the deposits are lessening after some harder stops, they feel better and the stopping power has improved significantly again. Obviously they need to be replaced. What next: I guess it would be fair to assume it's a heat problem. I wonder why I didn't feel the deterioration during the event or at least on the way home? I would really like to get CL Brakes pads again. Is there a weak link here that I can fix, e.g. exchange the stock rotors? Could they be the culprit? Not dissipating the heat fast enough? Would the RC5+ work better with grooved rotors? Is the 5 mm wear normal for 3 hours? Or is this a chain reaction causing increased wear once it went haywire? I assume some of the missing 5 mm are spread across the rotors now and that wear rate isn't normal? I consider RC6, but read they can cause sparks that damage paintwork. Also I've seen videos where they make horrible noise for street driving (the RC5+ are delightfully quiet). I also consider the RC6E but read they make a lot of dust that cake up (the RC5+ were very low dust). I use the car for spirited Sunday drives, track and occasionally daily when the weather is nice. Basically I would prefer to stay with the RC5+ what can I do that doesn't cost a fortune to rectify this? (No major cooling mods, that I would rather put forward to the Sprint kit eventually). Would a swap to other rotors helps? Are there anything obvious in driving technique that would cause this, that I can change? __________________ Build: T(h)or's GT86 hammer (Europe) - essential track setup Youtube: GT86 dude Last edited by Tor; 06-30-2016 at 05:12 PM.