Cracked rotor issues....
there are many factors to look at here, but the most important three are...
1. Sustained Heat input to rotors (you gotta cool 'em as best you can)
2. Rotor Material & Design
3. Braking technique
Number 1 has been beaten to death. Get some air moving on those rotors, or else, no rotor purchase will save you!
Number 2....most rotors are high quality in material. Some Slotted (best solution), some cross drilled, and some flat faced. Cross drilling removed precious material mass which can be used to disapate heat, as well as creating stress riser "starter points" (even though a circle or arched edge is the stronges we know of) but hey, they look kool. Drilled rotors always crack earlier, everything else being equal.
Slotted rotors function to vent the gas generated by the vaporising pad surface against the intence heat of the rotor. It is not a cooling issue, but a swipe the gas away issue. BUT, they too are also suspectible to cracking as all rotors are over time.
Basically, it is just a matter of time no matter what the choice.
OHhhh, and treating them cryogenically helps as well. This basically means that they are cooled really quickly from a high temperature (just below melting) when produced, using some sort of really cold substance to drop their temperature very fast. Think of horse shoe, glowing red, bucket of water...only instead of water....liquid nitrogen, or something else really cold....like one's ex wife's heart?!
If you are interested in what that means, keep reading, otherwise, we are done here.
When a metal based material is cooled it's properties are created during that cooling phase, as the grainular struture of the material is formed (production of martinsite, carbon grain boundries, etc). It a very material science technical issue (still intersted, see here
http://www.msm.cam.ac.uk/phase-trans/2002/martensite.html ,
http://www.anvilfire.com/FAQs/heat_faq_index.htm). I love this stuff, and you may too?!?
Anyway, all that is important to us wanna be race drivers is this.....the manufactures are using technology to make the rotors as good as possibly against cracking, with very complicated manufacturing processes, and for like 100 bucks each we take advantage of that. Once in a while, we get one that had a nondetectable stress riser, and it cracks a little earlier, but fo rthe most part, they do the job, as long as we do ours.....cool 'em, brake technique, and change them when they die.
Enjoy!
BTW, Hey Ojas...how the heck are you...have not seen you since waayyy back in the day....glad to see you did not let that boofed engine turn you track sour (what was that, like 5 years ago at TWS or something)!
