I have a some roads I won't ride. Then there is a narrow road with limited shoulders I will ride. I use my glasses mounted take-a-look-mirror. If I see traffic coming up behind me I pull off and wit a few seconds for it to pass.

I pulled up the google map satellite view for your area and it is beautiful! The birds-eye view is even more incredible, and the street view is astounding...although it does show how narrow the roads are.

https://www.google.com/maps/place/Du...6!4d-7.3561973