Originally Posted by stuntman

Did you read the thread? They OP seems to have demonstrated that the durability of the D2 caliper isn't up to snuff due to the poor metallurgy of the BBK:


"
Problems!
After the brakes performed well at the track I was pretty happy. On the way home from the track the next day things turned for the worse. While cruising at 100kph there was a sudden knock and then very loud grinding combined with quite serious banging. I pulled over and stopped the car gently and looked at the front right where the problem obviously was. With the wheel off on the side of the road it was obvious what the issue was, one of the bolts which holds the caliper and bracket to the car was gone! My first suspicion was that the bolt sheared off however there was nothing there in the thread, it was completely missing. This is highly dangerous to say the least, there are only 2 bolts in total which hold the caliper on. The initial obvious conclusion is that I had failed to tighten the bolt correctly, however I do recall tightening this upon installation, and because I know that brakes are your life on the race track, I also tightened all 8 bolts that hold the brakes on AGAIN before putting the wheels back on.

So I was stuck on the highway between Philip Island and Melbourne on Easter weekend (you can imagine how busy it was) with the sun going down and over 2 hours from home. A very good friend came and had a look at what the bolt size is, went and got the right bolts from home (no place would be open for 2 more days given the long weekend) and drove back, you certainly know who your friends are at times like these. When we went to put the bolts back on to attach the caliper and bracket again we found we couldn't get the second bolt to line up through the hub and into the bracket threads no matter how hard we tried and in our efforts damaged the thread in the bracket pretty badly.

It ultimately turned out (it's now night time on the side of a busy highway so visibility with a torch is poor) that the holes in the bracket didn't properly line up with the hub holes... they were out by about 1 - 2mm, and these clearly ligned up previously when I installed the brakes. From here I have a *theory* as to what the problem was. I think the bracket material is not quite right and was warped or expanded due to heat, and this is why the bracket no longer fits properly when before it did. This expansion also made the threaded bolt hole bigger (I know it sounds counter intuitive, but bolt holes get BIGGER when metal expands) which caused them to loosen and the bolts over time work themselves out which caused my problem. After repairing the brakes I checked the other side to be safe and indeed one of those bolts was also loose, I think this also backs up the theory that it wasn't installation error... to miss tightening BOTH sides is really unlikely. The holes in the hub also had gouges in them from the thread of the bolts which must have been exerting a lot of force on them.

After elongating the holes in the hub with a file (really strong metal as you can imagine) we were finally able to get the bolt to go in. Although tight, one of the threads is ruined in the bracket and while it was good to get me home once I pull it off I won't be able to use that bracket again, and adding to the frustration with the elongated holes if I ever want to fit standard brakes again or a new bracket I may have to replace the hub sad.gif The caliper has been pretty scraped up and deep scratches have been gouged into the inside of the wheel, and this event also knocked off the wheel weights so I had to drive home on an unbalanced wheel with a bit of vibration, so I hope my brand new expensive semi slick isn't ruined. All in all, not much fun. Had this happened at high speed I don't think you'd consider it to be too good either. Justjap says I'm the first person to experience this problem.

Just great....
"


I mentioned Rotora because "miata mx5" lumped Rotora in the same group as D2/Ksport. I gave my personal feedback initially agreeing with Rotora's quality and performance, as well as my personal experience and information about the changes within the company to raise their quality and performance standards to come up with a product that helped me win the longest sports car endurance race in the world (as per NASA's claims). I've driven on many manufactuer's products from AP, Alcon, Brembo, Stoptech, Rotora, Performance Friction, Wilwood, VRT (K-Sport?) and many of the "OEM" brembo "labled" products (many of the cars with OEM "Brembo" brakes are not designed or manufactured by Brembo - Ex: Nissan R35GTR, 350Z, EV0, Acura RL, etc...) It also sounds like you have made up your mind on going with the D2 brakes. I agree that some others are not basing their comments on personal experience but you are also not looking at the information provided.


0.02

Originally Posted by Marcel Burkett

This is not so , the guy clearly went wrong somewhere in his installation . He either did not torque the bolts properly ( no mention of a torque wrench ! or the required spec.) or did he use any LOCTITE . If you read on you would see that other users had no problems with the bolts at all .

Originally Posted by stuntman

Did you read the thread? They OP seems to have demonstrated that the durability of the D2 caliper isn't up to snuff due to the poor metallurgy of the BBK:

[snip]

0.02

Originally Posted by habu2

oh so you were there and know this for a fact?

Originally Posted by Miata_mx5

Let him buy his **** brakes and go blow them up on a track day or something.

Who cares anymore.

Originally Posted by jeroentje.nl

We have 4 track cars running K-sport.
It is working ok for us.

Also check time attack in the UK.
The top cars are running K-sport brakes.

You can fit brake pads like:
Ferodo
Hawk
brake performance
etc.

There are also 2 compound discs.

bad picture ... was making a splitter :-)

Originally Posted by Marcel Burkett

This is not so , the guy clearly went wrong somewhere in his installation . <snip> If you read on you would see that other users had no problems with the bolts at all .

Originally Posted by jeroentje.nl

Any problems with the bracketry ?
How does it compare to the stock FD brakes ?
Where do you buy replacement pads ?


No problems at all.
Much stronger then stock.
Pads: everywhere