Question about balancing rotating assembly

Roger... the end journal weights have about 3x the effect on primary balance versus the weights on the center 2 journals.

BTW, torsional vibrations in the crank have nothing to do with balance, nor are they any consideration in the balance work that we do here. It is at a very much higher frequency, like 6000-8000 cycles per second (Hertz) versus the primary balance vibration that would be at 100 cps at 6000 RPM.

In reality, a few of us know 'a bit' more about this than are being given credit...