The area you are looking at around Dordogne is great...but, it is busy in season and really a tourist mecca. Dont ignore fantastic roads around Clermont Ferrand, Le Puy and the national parc below Saint Etienne. All much, much less traffic. Just search out the D roads and streetview them on gmaps to get an idea and to plan routes.
Just a few weeks since meeting up with some mates from the UK, we stayed at Le Bessat (Hotel de France) for our 1st and last night. Great location to start a tour from and they will let you put the motorcycles in their garage.
Great thanks. Bit Unsure yet as to when we will go.