If so which one are you using?
I've thought about the saris bones but I think it might mark the boot
The one that attaches to the luggage rack looks good but no idea where to get one
I've used a Saris Bones on mine for a couple of years now. Helicopter tape on the bootlid to stop it getting marked, however the aluminium bootlid is pretty flexy, and after 2 years the rear edge is now not flush with the body 🙁 Having said that, if you can avoid looking in the mirror, it works. I also avoid putting two bikes on it now as well, actually I prefer taking my wife's car with the roof rack these days...
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Not really answering the question, but I have a MGF, and my bike fits in the passenger seat.
Take both wheels off, and it gets in easily.
When muddy, I just put an old sheet over the seat.
No good if you have anyone else in the car though.
Alan.
I always thought this was worth a look too:
http://forum.miata.net/vb/showthread.php?t=411954
Very neat solution, but the hassle of fitting and ordering from the states.