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HI Guys,

I dropped my car off to Mania to install a Adaptronic and when i picked it up on the way home after a few hard brakes i found Sparks flying out of the wheels.

Here is a video of it happening.




I also noticed the little rubbery piece at the bottom of the drivers side caliper was glowing RED and smoking??
WTF!!!!






I thought it was coming from the Passengers side so i pulled the wheel and caliper off but the pads looked fine and nothing was odd.
Went for a test drive and after say 3 harder stops the sparks flew again and the drivers seemed worse but sparks on both sides.
That is when i noticed the smoke and found the red glow.

They are Carbotech XP10s on the front but they have been on for like 8000 ks without this ever happening.

Any help much appreciated.
I am serioulsy stumped how this can just start happening especially on both wheels??

i note you have pulled the wheel off, is it rubbing on the wheel itself? There has to be a place where it is rubbing, look for them.

Nothing appears to be rubbing.
It is only under hard braking.

About the 5th brake then they start.

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It may take more time. But I would pull wheel off and start pulling the brakes down bit by bit. That way you can properly check.
It may be something jamming under hard braking. Possiby a cylinder sticking a bit.

That's opposite the end of the caliper mounting bolt slider pin - may be caliper sticking.

Thanks for the help so far all.

I will pull the drivers side wheel off tonight and remove the caliper and have a look.

The night before it all seemed to be the passenger side which is why I went in there first.
I checked the pads and pins. All looked good I re greased and put it all together.
Then on the test drive the drivers side was going crazy.

I sent an email to Emilio at 949 and he replied saying that is to be expected if you change rotors and it might die down.
I have not changed anything though.
It seems excessive to me and the fact that I have run on these for over a year know with track days etc and never seen a spark ever.

So very very strange.
I hope I can explain it soon.
Hate the crazy issues

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I run XP12's on my car. Some serious heat and a few sparks are to be expected but not at any sort of sensible speeds.

I would suggest that either the caliper is sticking or more likely the piston in the caliper is sticking and you need to do a rebuild with fresh seals.

Thanks for the advice.
The calipers were rebuilt when the pads and rotors went on.
Rebuilt by a brake shop.
But who knows.
Clearly something is wrong.
I hope the drivers side shows something obvious when I pull it apart.

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The XP10 and XP12 combined with sticky tyres and track use will get your rotors well north of 600c. The back of my brake pads are entirely scorched, the surface finishing is burnt off and the thermographic paint on the rotors is burnt off. The rubber seals in the calipers, rubber boots on the slider pins and the slider grease all become service and consumable items at these temperatures.

The glowing bolt / slider pin is highly unusual, something is hanging up and causing the pads to be in permanent contact with the disc and is transferring all that heat in to the calipers. Ideally you won't be driving the again car until it is fixed!

dont forget to check for play in wheel bearings.
Mick

Could wheel bearings cause the sparks ?

I'm not quite sure what the sparks are?

Could it be really hot slider pins getting hit by brake pad residue and igniting or would that not occur.

I find it crazy that it never did it and then I left the car for the ecu installation for a week and when I picked it up it did it.

I have not been able to notice a wheel being hotter than normal which in the past when I've had a bent slider pin the wheel was really hot.
The heat is actually what drew my attention to it.

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They're race pads so that sounds pretty normal to me. I've had it with the carbotechs XP12's and the hawk DTC-70's I have now are much worse on the wilwood calipers. I seldom drive my car anymore but I've nearly caused an accident before scaring the crap out of an oncoming car when I had to brake suddenly and it shot 2 meters of sparks out both sides.

Thanks Hellmun.
Just so weird that in over a year of these pads I have never had the sparks happen.
And now they happen just on the street.

I checked out the drivers side and all seems fine besides the melted lower pin boot.






I pulled the pin and it appears to be straight.




The pads appear fine, slight taper which they always seem to do.




So I just regreased the pins and went for a test drive.
The sparks were crazy but after about 10 stops they seem to die down to none.

I will try again tonight to see if it is a heat thing or if maybe there was a build up of corrosion or something as the car had sat for a bit over a week at mania which it never does.


Still strange that it just started but hopefully it is a non issue from now on.
Not sure why that lower pin boot melted a bit. I guess something has jammed a bit.



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My HP+ spark a lot but need to get some temp into them and brake pretty hard.

I had pad taper wear like that until I put in new slider pins. The differences between old and new pins were barely measurable.