It's a very importatnt thing to get right and also a fairly simple thing to do. Most hulls like around 30-33% as a starting point for the COG. Figure your hull length and divide it by 3. That will give you your starting COG (33% forward of the transom) I make a mark on both sides of the inside lip of the hatch at that point. (with boat ready to run, all hrdware/batts/etc) Hold the hull at that point with your fingertips. It sould stay level in your fingers. If it leans forward that means your COG is farther forward, if the transom tilts down it means your COG is more rearward. Hope this helps.
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