The fine art of flywheel balancing. Weigh all parts that latch on to the crank, including circlips, etc, everything. Choose approximate rpm range desired, plug in to H-Ds specific balancing worksheet, make sure female rod is relieved for strokers,
if not original KH rods or if building 5" stroker. Out pops magic numbers that you turn in to the actual Bob weight. Than get busy...drill baby drill. First big chunks than smaller. H-D states properly done should be 5 or less balance holes. Last 5" stroke 61.5" KHKR I built wanted some weight added to proceed...in that case drill in, tap the hole, fill with real lead. Go some more...when done the assembly should sit anywhere you turn it. Erik