Originally Posted by
cj_rst
Check out the science behind warped discs - skimming them can be a false economy. When the disc warps you get a hot spot compared to the rest of the disc - because of the concentrated build up of heat the composition of the metal in that area changes. Therefore you can skim the disc flat again but the area of the original warp will re-warp when it gets hot. Might be better just spending out on new discs.
Bang on the money!!
Disc "warpage" is caused by DTV, disc thickness variation, it happens to all to some degree or other, you don't need to shell out on pricey overpriced AP replacements though, there are others.
It is certainly worth checking the run out of the hub face, and using a dial gauge on the disc when fitted to get the run out a slow as possible, you have a choice of 4 different positions on the hub alone.
tabetha