The reason I ask is that I have a tandem kayak that's 72 lbs, not counting the aluminum paddles that I carry on it, and not counting a couple of pounds' worth of extra equipment I store in it. Since I want to carry it with foam blocks on the factory crossbars, I'd probably be slightly above the stated weight limit. And I also cinch the straps that hold the kayak onto the rack down pretty snugly, so it's not like the kayak would just be "resting weight" on top of the racks. Which gives me pause
