We purchased two sets of these and used them on the Yakima roof racks on our pop-up camper. Assembly took less than an hour and attaching the 4 bikes took only 30 mins. We had two bikes (one youth/one adult) that had thicker support bars, so we just took apart the crimp assembly, placed it around the supports and then ratcheted them down like they're supposed to. We traveled 600 miles at highway speeds and only had one tire wobble. Overall, we are very pleased with the cost and performance of these racks!
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