Counterweight opposes counterweight and rod journal opposes rod journal. Something that has never been mentioned before is also the front half of the crank is also balanced to oppose the rear half of the crank. A static balancer is ineffective in telling you if that is occurring or not occurring. We had a Sterwart Warner balancing machine that is so sensitive it can tell you to within a few grams if the crank is balanced. On a static balancer, you can still be more than 30 grams out of balance and the crank wont spin or rotate to indicate it's still out. Fine for a shade tree fix, but the out of balance the crank can still have is not really balanced if you are having to pay for it.
