I travel with some large boards (Mistral Unlimiteds & 14 ft. race boards) for long distances at high speeds in strong sunlight. While for a 11 ft. board the typical 36" spacing on roof cross bars is OK when you get to 14' or longer and especially with a cover, I would start to get nervous. I use a Goodboy Kayak rack with the flatter V bars and their shock cord tie downs vs. straps. To me tie downs on a fragile race board is an accident waiting to happen. I run a double set with the second one with slightly less tension as a back up. Kore Dry makes a fine product, and would not recommend the more protective covers for travel, as they can become a disaster in a heavy rain storm, as they can fill up with water.