The fulcrum is the pivot point where you hold the reel. It doesn't change with the size of the reel. The center of gravity does change, but that only changes significantly if you old the rod in front of the reel, as on a fly rod. (ie adding weight with a heavier reel to counterweight the rod only works with fly rods)
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If every fisherman would pick up one piece of trash, we'd have cleaner rivers and more access.