ZN1100 main jet spec

Was looking at the FSM carb jet specs for the 84 ZN1100. It shows cyl 1 & 4 take 122.5 and 2 & 3 take 127.5 main jets. That's two steps!
Why on earth, and how would that spec. apply to my 82 KZ1100 with the ZN head on it? I've been running with 132.5 X 4, and it sure seems to like it that way... :whistle:

maybe 'cos 2 and 3 run hotter since they're in the middle? extra fuel keeps it cooler and prone to less pinging? not sure, just shooting in a bucket here 'cos that's some of the thought when tuning; fatten it up a bit so we don't melt things.