You've downsized your vehicle, but not your lifestyle. Now you have a new problem: where to put all your gear. If you've got too much junk for your car's trunk, the best place for it might be on the roof. No joke.

While roof racks have been the obvious solution for years for toting large gear such as bikes and boats, you might be surprised to hear that modern rack systems are designed to accommodate a much wider variety of other cargo, including everyday items such as clothes and groceries. European drivers, who have been thinking small for generations, long ago adopted rooftop cargo boxes as auxiliary trunks. My friend in Finland calls his a "mother-in-law box." (That's a joke.) Consequently, today's racks have transformed into base stations, designed to haul everything from surfboards to an extra spare tire.

But racking up your gear, and getting down the road safely with a load on the roof, is easier said than done. It requires a little planning. You don't want to look like Jed Clampett headed to Beverly Hills, do you?

Here, we run down the rack basics so that you know what's available and how to use it.

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The Modern Rack
The gear rack has come a long way in just 30 years. It used to be that if you needed to carry a canoe, for example, you would pick up a pair of cast aluminum brackets designed to clamp onto the rain gutters of any car, and then you'd bolt on a length of 2-by-4-inch lumber cut to span the roof. Add some eye bolts for tie-downs and you were in business. The same makeshift rack could carry lumber, ladders, skis and even a Christmas tree.

In the late 1960s, Yakima Products added to its line of metal hardware a roof rack designed to carry orchard ladders. In 1979, the company was purchased by two kayakers who struck on the idea of creating a modular roof rack for boats, with other accessories designed to carry different types of gear. Thus was born the modern "rack system" concept, along with an industry that today is dominated by Yakima and Sweden-based Thule.

Growth in the rack industry has been fueled by the boom in gear-intensive adventure sports, and by modern vehicle design. Cars no longer have rain gutters at the roof seam, and the shorter and curved rooflines of today's aerodynamic vehicles mean that the rack bases have become more specialized. Some still clamp to the roof above the door, but others are designed to work with the factory-installed roof rails or tracks that come on many SUVs and vans. Others bolt directly to "hard points" on those vehicles. Both the Yakima and Thule websites offer guides that sort out the mounting options for specific vehicles. The rack feet support crossbars, which also come in various styles and lengths to fit different vehicles and loads. Wider bars, for example, can be used to combine outboard bike racks with a center-mounted cargo box, or be wide enough to carry two canoes. On the feet and bars are mounted gear-specific accessories, or a cargo box or basket can be changed out quickly to suit the weekend's mission.

The complexity of fitting a rack means that it can be a good idea to get advice from an experienced retailer. "Assembling some of these racks for the first time can be a bit of an engineering project," says Peter Coons, manager of the Wheel & Sprocket bicycle store in Appleton, Wis. "The rack also needs to be located correctly on the vehicle. The rack manufacturer has critical mounting specs for each vehicle on the road, measured down to the millimeter. If the rack is not installed correctly, it can void the warranty. We install all the racks we sell for no charge, but other retailers may charge for that service."

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Original Equipment Manufacturer Systems
Many SUVs and station wagons come with a factory roof rack, but these racks often are not rated to carry much weight. The factory rack on a Ford Escape, for example, is rated for 100 pounds. That includes the weight of other rack components, and a medium-size cargo box alone may weigh 40 pounds.

"Some of the OEM racks are more cosmetic than functional," says Yakima Product Manager Eric Roesinger. "Styling and wind noise are bigger concerns than utility for auto manufacturers. Our racks are rated to carry 165 pounds, but that's more a function of vehicle dynamics — how weight on the roof may affect handling and braking — than the strength of the rack system."

The crossbars on OEM racks are also usually no wider than the side rails, which limits the space available for bulky gear such as kayaks. Rack feet like the Thule 4502 Crossroad Railing are mounted to raised OEM side rails to enable the use of wide load bars.

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