This project started several years ago after outfitting the family with mountain bikes to ride on vacaton. Since we pull a popup trailer, a trunk mounted rack is not practical. Those cartop Thule racks that have become a badge of 'yuppydom' seemed like a good solution. But jeezum crow, first you gotta shell out over a hundred big ones just for the 'sports bar,' then the individual bike carriers are $75 bucks each. By the time I bought the racks and four carriers I needed, I could have bought another real nice bike!
No way was that going to happen, so I set out to design some type of a roof top carrier. After fooling around with a lot of ideas, I realized that the Thule setup is really a good design, and maybe I could copy it......for a lot less money. The first design was built as a one-piece unit.....all four carriers built onto a platform that set onto the car roof (on pads) and strapped to the gutters. The problem was that each time we bought a new car, a new platform needed to be built because the roofs and gutters varied. Eventually the rack evolved to something that is more portable, and will fit a Thule sports bar, or any generic roof-rack. In this latest incarnation of the design, each stand is a seperate unit, allowing versitility in the configuration. Also, the carriers can be removed to allow the roof-rack to be used for other purposes.
The basic rack is constructed of parts that you can find at the hardware store and lumber yard. For tools, you will need a drill, vise, wrenches, hack-saw, and wood saw: a table saw and/or band saw is helpfull.
The design is essentially the same as a Thule...we call it our "Fhule." From the photo to the left, you may already have identified some of the key components. The track is made from 2" PVC pipe ripped lengthwise, and mounted on a 2x2 for rigidity. The stand is shaped from electrical conduit. Nylon straps hold the wheels down, and the entire carrier is attached to the sports bar with U-bolts.
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The stand attaches to the base, and hinges on a bracket cut from angle-iron.
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The carrier is attached to the sports bar using squared off U-bolts and wing-nuts.
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By mounting the carriers in alternate ditections, you can fit four bikes on a 48" sports bar or similar roof-rack. This rack lacks some of the conveniences of a Thule: mainly the quick release fittings (and locks). This is also not a rack that you will want to leave on the car all year. But it is a sturdy economic alternative to the costly Thule and Yakima bike carriers. It has carried our bikes on several long trips, and proven to be very roadworthy.