In the rigging section here, we have one more where Ed Whited used a couple of angle brackets from Home Depot I believe. The page is
http://www.allkayakfishing.com/rigged/wallmnt.html I store my kayaks on their sides leaning against the wall, cheap and easy. If I was going to have the kayak being supported or sitting on bars of any type, I would put some extra padding on the bars or rods if I was going that route to help distribute the weight a little bit. Thinner kayaks may be a bit more apt to get slight indentations in the plastic from storage than others, so padding may help a bit. Just my .02,
Perry