I tried finding some universal roof racks, but nothing that great. I have, however, had good luck with the rear decklid/hatch/trunk strapie-doodjey bike carriers.
Thule Rack
I used a similar, cheaper one on a Van, Bug, and a Civic notch back. The only problem I have with it, is that it offers no security when I leave my bikes locked to it. Anyone could just cut the straps and take off with two bikes, on a nifty little rack to ease thier thievery. While hooked up to my camper van, I would run a cable through the bike frames, and down to a tow hook under the bumper. I'll have to try the rack on my Rio5 when I get off in the morning. I'll let you know how it works.