Hi tomas!, you are going to one of the better places in Spain for MB (and for windsurfing, and kite, and...).
You'll probably find there colleagues for your ridings because the surroundings of Tarifa and his bay are perfect for MB, (specially the few days with no wind).
The Hurricane Hotel is well situated, nice and comfortable, used to be a perfect and classic choice for windsurfers and kitesurfers, and I suppose they can inform you about MB renting, but in the case, try this:
http://tarifa.costasur.com/sites/bike-rental/es/
or this:
http://www.aytotarifa.com/Turismo/ALQUILER%20DE%20BICICLETAS.doc
or simply Google a little (in spanish "alquiler de bicicletas en Tarifa", but Tarifa is extremly international, and I'm sure you can Google in english)
Just a point: in spanish "tarifa" means also "rate", so you must be careful with this "false friend"
¡Enjoy your trip! and think for the future to ride in Córdoba, we are about three hours away from Tarifa, we have perfect terrain for MB, the mountains of "Sierra Morena" , and a friendly and deeply historic city.
By the way: Where do you come from in Sweden?
