HPDE / track drivers - keep an eye on your rotors
 

There's a crack on the face of the rotor.

https://farm4.static.flickr.com/3287...db0de264_b.jpg

I noticed it when changing back to my street wheels at the end of a two day track event. I don't know at what time the crack started, but I feel like I dodged a bullet.

Rotors are Texas Speedwerks. Brake pads were Carbotech XP10 (and Porterfield R4-S last year).

I ran 45 minutes straight at the end of the second day, in 90° heat... so I'm sure the brakes got very hot.

WOW, those things have been hammered like a drunk prom date!:thumbsup:

You call that a cracked rotor?

This is a cracked rotor!! Wilwood 12.2 slotted and vented, Raybestos R-43 Pads, brake cooling ducting.

http://lh5.ggpht.com/gnatster/SItr-M...20Wilwoods.jpg

Temps in the 90's 30+ min sessions. Track has long straights with heavy breaking areas.

After seeing what happens when a rotor fails completely at ~50mph (someone else's car), there's no way I want to experience it myself. Especially going into a braking zone at ~90mph.

Thanks for the heads up snid.

I have a friend that had a simular crack in one of his TSW rotors. I've had cracks in my stock rotors after my last track day. A failed rotor can be catistrophic! Everyone should be checking theirs before & after track days.

I hear ya snid! For our own safety and the safety of others we share the track with, keep an eye on those rotors!!!!


Jason
https://www.northamericanmotoring.co...orIBX_0026.JPG

Hmmm... another TSW rotor with a crack that looks much like mine... :confused:

These are no really cracks... have a look at this here:

BTW, original Brembo rotors used ONLY in all-day-driving with ceramic brake pads... frightening !

Those are definitely some scary cracks propagating from the cross drilled holes on your rotors!

As far as not being real cracks on the other pictured rotors, speaking for myself, if I can stick my fingernail down inside of the crack, it fits my definition of a real crack!

Jason

Those are some scary cracks Carter. One reason why I'd never use cross drilled rotors. I'm amazed they look like that considering they were not on track. WOW!:eek2:

Is there such thing as a "safe" crack? I think I've read here somewhere that short, barely perceptible cracks are ok, but once they're past a certain length/width, its time to replace. I have some short, tiny hairline cracks--don't know if I would have even noticed them if not for your post. I'm replacing the rotors soon anyway, but I'm wondering if as soon as you see cracks they should be replaced, or if you can get a bit more mileage out of them if the cracks are a certain length/width. With time, there's no doubt that the small cracks are going to get bigger, so if the consensus is replace as soon as they're visible, so be it...

Gnatster, how many events did you have on those rotors? I have the 11.75's, but no ducts (gonna be my winter project), and these rotors have been on for only 3 HPDE's. I'd be ok changing rotors every 5 events, but 3 is a bit much...On the other hand, I love the setup I've got with 15 inch wheels/rims; the gearing change is favorable to the point that I rarely need 2nd gear on the track (on some tracks I don't use it at all), which is a nice luxury, and the braking/acceleration is so darned good I really don't want to go up to 12.2's and have to start all over with new tires/wheels, and although 1.25 inch 11.75 brake kits are available, I'm not in the mood to buy another BBK. Here's to hoping a bit more TLC and brake ducts will keep me in the setup I'm in at present.

Well...guess what.... On Saturday I was switching from my street pads to my race pads, I happened to notice this on one of my fronts:

https://www.northamericanmotoring.co...stosRotor1.JPG
It's hard to see in the pic, but this crack is all the way thru to the open center "vent" of the rotor.

I guess I wasn't being over cautious when I purchased a spare set of rotors to keep in the shelf......
These rotors were used for street and autox only, not a single track session on them!!!


Jason

Jason have you considered going with cryo'd rotors? From what I understand they are supposed to be more durable. Or maybe that is just hype I've bought into.

I've also heard cryo is a good thing, but I've never tried them. I was very very surprised to see this crack appear, I didn't think I was putting enough heat into the rotors to do this sort of damage since I've stayed away from track days this year.....I guess not.

3 events total, plus Dragon a few times. The killer was a real highspeed track with serious braking zones and long 30-40 min sessions.

Some more info here:
https://www.northamericanmotoring.co...ghlight=cracks

My rotors looked like Rustyboys--I'm going to hang on to them for street use, and I just put brand new ones on for the track, I wasn't sure if they were going to be ok or not, and I'd rather error on the side of safety. Glad I did, because it looks like the tech inspections are getting a bit more formal, and I have a sneaky suspicion I would have failed it with those rotors, although you never know. Next plan is brake ducts, might try carbotech pads down the road too...Still using Poly B's at the moment, which I've really liked (and do great for the price).

Problem is I'm hooked on 15 inch wheels/rims, and I really want to stay with this combo. I'd like to get 5 track days out of the rotors (a full season for me), maybe that's too optimistic...If all else fails, maybe I'll go with a bigger BBK and run 16's or 17's, but I really hope I don't have to...

There is always the TSW BDM BBK....

http://www.txwerks.com/servlet/Detail?no=132

Just did the first DE with them, and am very very impressed. Last year I spent half of each session managing brake fade. This year it was deep into every brake zone. Couldn't be more pleased.

Alan

Just a few things we have learned from our customers running track events.

Buy the right pads for the rear too. Our customers running Carbotech XP10 front and XP8 rear are getting 4-6 track days out of pads and getting 2 sets of pads to each set of OEM or "plain-Jane" rotors.

We have learned it's the pads that make a big diff on rotors. Carbotech pads do not heat up rotors like many other pads.

We understand that each track and driver will make a big diff on the brake issues on any given MINI. We also know that the right pads front and rear are the best way to minimize the issues.

We have many customers running the XP10/8 combo on OEM/replacement rotors without issue.

We also know any pad/rotor combo can be pushed pasts it's limits and fail. There is no "one-size-fits-all" system.

After all, why risk an investment of $20K in hardware, your event if you go off track and maybe your health just to save a few hundred dollars on pads and rotors?

Shaking Raised Fist at you....

Between you getting braking and Scott getting a suspension I'll never be able to keep up!!

don't worry about those micro-cracks til they get to the edge of the rotor and through to the otherside of the surface. until then drive it like you stole it.

I would stray away from ceramic pads for performance driving. The trap too much heat.

Not all ceramics have issues. Many NAM members are running Carbotech without issue. I also have them for your 09 JCW.

I think the only selling point of ceramic pads is low dust. nothing special about their braking ability. they only make ceramic pads for street use.

FYI

The Carbotech TRACK (XP8, XP10) pads are not low dust or quiet.

The Carbotech 1521 (Bobcat) Street pad is low dust and quiet and better stopping power then OEM.