Don't really know much about Spain so any info would be much appreciated.
The Spanish are a parasitical, bone idle race who will soon be crashing out of the EU. They kill millions of bulls every day by throwing them out of bell towers. I read it here.
You could start with this book:
Better still, just buy a copy of ‘The Rough Guide to Spain’ or Michelin’s Green Guide to Spain.
Me and SWMBO will be travelling from Bilbao to Malaga in August and am looking for some advice for places to stay / things to see en route
Bilbao to Malaga direct (very nearly a straight line north to south) is just a touch under 1000 kms or say 630 miles. You have three days, so that is 210 miles a day, if you round the numbers. Probably further as you have decided to miss out Madrid (who told you to do that?) and you want things to see in the peak of summer and places to stay enroute? Just how much of your three days do you want off your bike ‘seeing things’ whilst you trundle along your daily average 210 miles?
Divide the journey up, say into three equal bite sized chunks, which will give you very roughly your over night stopping points. You only need two as your third night will be in Malaga.
RiDE magazine’s website has suggestions on north south routes, you may be able to adopt / adapt these perhaps?
Go to the ViaMichelin website. Insert Bilbao / Malaga. Chose motorcycle. Select avoid motorways / toll roads. This will at least give you a route that swerves around Madrid, bending like a bow to the west:
It’s 1,200 kms or near enough, so roughly 20% further than the direct route.
Then do the same thing again in this excellent routing website:
https://kurviger.de/en
Which will give you:
Play around in it, you can’t break it.
PS Book your tickets in advance for the Alhambra