The most recent info we have is that you need a travel agency in Libya to organise your visa. It seems to be variable as to whether they have to escort you or not, possibly depending on your country of citizenship. No particular hassles with a vehicle, other than they will issue temporary Libyan plates at the border which you must be able to affix to the bike.
Pete & Kay Forwood (Australia) went into Libya via a tour agency, but never did a tour, just drove themselves through with no problems. But that was last year!
Good luck, let us know how you make out.
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