I am in the same boat here, my threads just keep pulling out of the cases. the right case to be exact. I have had them filled, then drilled and welded time serts into them and it is still pulling.. I am 10 over with a stroker kit and all the head work done. I'd like to keep it HD but with that kind of motor, am I better off putting an aftermarket with the crank bore already done? I am tired of splitting the cases on this bike.. done so 4 times in one year already cause it is spitting head gaskets