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higgy wrote:Pure bullshit, Sintered pads are the issue with cast iron rotors. the only advantage to stainless rotors is their corrosion resistance period. As a friction material they suck the big one. Truth is any non-sintured as in organic pad will give you superior braking with iron rotors. Got two pistons just get a set of braided steel lines and don't use Sintered pads

higgy wrote:
Pure bullshit, Sintered pads are the issue with cast iron rotors. the only advantage to stainless rotors is their corrosion resistance period. As a friction material they suck the big one. Truth is any non-sintured as in organic pad will give you superior braking with iron rotors. Got two pistons just get a set of braided steel lines and don't use Sintered pads


Er... Mr Potato Head doesn't use sintered pads with a cast iron rotor. I already said that I changed the pads to sintered when I changed to carbon-steel rotors. Previous was organic pad with cast-iron rotor. I wouldn't make a newbie mistake like that. Carbon-steel rotors work a good few hundred degrees hotter that cast iron and aren't affected by wet weather. Is there any other part of the post that you think was iBS?

Traditional iron brake rotors such as widely employed in the automotive industry and to a much lesser extent, in the motorcycle aftermarket are Gray iron. That material is features a distinctive coarse flake molecular structure and typically suffers from issues of porosity that can lead to failures associated with thermal stress induced fracturing. To address these inherent material weaknesses, improve their failure resistance and increase thermal capacity, they are typically big and heavy. This whole reliability issue is made worse by the nearly universally employed individual mold casting technique...cheap and efficient to be sure, but also guarantee's even more problems associated with uncontrolled porosity.
The widely reported untimely demise of Jimmie Adamo is much as described, but that too was Gray iron and simply not up to the task.

The Ductile iron family is a different animal, developed in the mid 1940's specifically to deal with the inherent brittleness of Gray iron. Ductile iron features a unique spheroid - nodular molecular structure that introduced "ductility" into the matrix. This brought many benefits to the manufacturing industry with a much more reliable base material including substantially higher tensile strength, inherent resistance to thermal stress induced fracturing, improved thermal conductivity and more. Within that broad family of Nodular (ductile) iron, there are many variations, just like there are in the general steel family. Without getting too boring with unnecessary minutia, suffice to say the specific grade of iron used in the manufacture of BrakeTech AXIS/Iron rotors is an optimal alloy with a closely monitored and proprietary heat-treating process employed for both stress relieving and material hardness. We also utilize a specialized in-house Cryogenic treatment of LN in a computer control vapor system at -300F. Contrary to what is out in the ether sphere of the web, the cryo processing we employ converts austenitic carbon/graphite atoms to martensitic for much improved wear (abrasion) resistance. Our testing shows the cryo processing has little real-world affect on relieving residual material stresses. That aspect of manufacture is addressed in our proprietary and more traditional heat-treating.

Also, unlike the individually molded Gray iron mentioned at the outset, the BrakeTech ductile iron is manufactured from true billet, no individual molding here. We quite literally saw blanks from continuous cast bar containing virtually zero porosity. Every step of manufacturing is closely monitored to a remarkably high level and ISO 9001 standards (each finished iron blade is micro laser etched with all relevant batch and date info, look closely at the patented and trademarked Direct-Link "tooth" and you'll find that).

Quick note on perceived weight of iron versus stainless; contrary to popular belief, the misconception that iron is heavier than stainless steel is simply not true. The density of iron is slightly lower than that of common stainless, so for a given volume of material, iron will be somewhat lighter. Perception always plays a role; kinda like asking an unsuspecting friend, “which is heavier, a pound of feathers or a pound of lead?”

Lastly, the real reason the OE's don't use iron is primarily one of aesthetics; the potential of rusting rotors is very simply not palatable. A secondary reason is the greater expense of manufacturing from a proper grade of higher spec ductile iron, costs are always an issue. And lastly, advances in friction material technology for use on stainless steel have come a long way, their performance as well all know is nothing short of brilliant...it's just a bit better still on iron!

My apologies for the lengthy response...it's a convoluted subject so "sound bite" like replies doesn’t cut it.

Best wishes and safe riding to all.

Jeff Gehrs
BrakeTech USA
Iron Brake Rotors - Ducati.ms - The Ultimate Ducati Forum
If it was a pure performance decision, the decision would go to iron.

Mc tool wrote:You could have painted the fork sliders too

Andrew2 wrote:Nice work for a fella without a bench


Cheers
A2