HAve been several times, stayed in Llanes, on the coast, and closer to Potes. There's some cracking riding – I'll have a look at a map if i can find it, there's a nice descent that drops you back just outside potes iirc.
Also well well worth it is from the top of fuente de- follow along from Potes, get the cable car up (when we went you had to get there early, they only took bikes on the first few cable car trips) – then follow back down, around, over along to sotres (i think) – ace.
There's a piece in the current singletrack I've not read yet- a glance looks like the area around carres gorge.
Cider and cheese, a must.
Si