I use a HF trailer with two 4" PVC running the length and I never cover mine. I keep mine in the garage so no need to cover. If I left it outside then I would cover it with a tarp to prevent the sun from causing damage.
I haul my boats either with a 10' utility trailer or my truck and use a TracRac which interchanges between either. If I'm taking a sit-in (touring), I'll use a cockpit cover. I also have a Commander 120 that I'll cover if rain is probable. Other than those situations, I don't cover any of my boats in transport. Just like kickingback, my boats are stored indoors...if stored outdoors, I'd definitely cover/shelter to prevent UV damage.
I haven't hauled my kayak. But recently, I got some helpful hints when my friend transported his kayak through a shipping company. The shippers had used a travel trailer, loaded the kayak and placed it directly on the crossbars upside down and secured it with hand-tightened tie down straps. After which they packaged and cover it as it was an open transport. I then understood that covering it properly can secure the kayak from scratches and damage to its body.
The ease of getting your canoe or kayak from the garage to the water is one of the big draws to the sport. There are three basic approaches: throw it on the roof, plop it in the bed of a truck or trailer it behind your vehicle just like a powerboat. Here are some tips to make sure you pick the right option.
Thinking of options, but not sure where to start? Options For Dummies starts you from the beginning with clear, step-by-step advice on how to use top option strategies to reduce your risk while boosting your income and enlarging your retirement portfolio with index, equity, and ETF options.