i dont really like the roof top racks, in my opinion, for the money you could buy a class 1 hitch ($90) and a hitch mounted bike rack( another $90). you wouldnt have all the aero drag and you wouldnt have to physically lift your bike onto the roof( probably a 2 person job to do it right) just my opinion.
1-1/4" Bike Racks and Carriers Trailer hitch bike rack and trailer hitches - etrailer.com
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