We’ve got a Fiamma rack for two bikes; they are easy to convert for more, you just need to get some new rails and the over-the-top clamps for the top-tube. How easy it is to actually put four bikes on may be another matter; two is fine, occasionally it requires seat raising or dropping to clear the other’s handlebars, but four might be a bit of a pain.
Our boot door will stay open with the rack on; some people have the problem of the door not staying open at all, which requires regassing the struts to fix.
With a bike on you can still get into the boot without too much bother, it’s heavier to lift up but because of the fairly high centre of gravity once it’s up it’s easy to hold. My trick however is to forget about the bike and just let the boot lid drop most of the way under gravity, which it does considerably faster with a bike on – ouch!
We’ve got an awning that is basically a curtain that hangs beneath the open boot lid; it came with two support poles which we use very occasionally to hold it open if there is a bike on.
If the roof is up and you’ve got a bike on the boot won’t open all the way because the bike bars hit the roof unless they’re really short (ie. road bike).
Our fiamma rack is great, although the metal parts of the rachets corrode and get very stiff. I believe newer ones are made of plastic to avoid this problem.
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