Importing MX bikes

I don't know about importing, but don't expect any motor sports in this country!  As you said, it will just be playing in the desert.

I have found the Reem track near Riyadh, http://en.wikipedia.org/wiki/Reem_International_Circuit does anyone know of any clubs that organise anything in the desert? If riding in the desert do you need the riders and the bikes to be licenced?

Yes I know about Reem, but from what I know, it is mostly a playground for Saudis.  As for dirt bike groups, I am sure they exist, but the hard part in this country is getting info.  Not every group or organization has a website or a known contact person or number, and most activity groups are informal and/or groups of friends.

I would suggest googling furiously for a good hour or so, and calling every number you can find and sending an email to every email address you can find related to desert riding/driving.  Good luck!

Thanks will do that when I have a spare hour or two.