I'll usually size a chain first with the longest length that the system will tolerate. Then see how it shifts. Only if there are shifting issues (or pulley knock that won't adjust out) will I remove links, and end up with a chain length towards the shortest that the system will handle. I do this so I don't have to add links and suffer the chain with second connecting devices (be they pins or connecting links). Additionally this allows for in the field chain repairs requiring link removals and have the chance of not ending up with too short a chain. Andy.