Hi Cathy, I did both Camino's last year in September, where I started in San Sebastian. The Del Norte is wonderful but probably one of the more expensive for accomodation. I stayed in a lot of private accomodations and hostels where I found them to be less full and more bang for your buck. There are some areas of the trip where if the guide says' Alternative route for cyclists" then take it. I found I wanted to stay on the walkers route as much as possible but there were a few times where I ended up pushing the bike up some of those single tracks and or finding the road to make it easier. It is definitely all doable by bike. On arrival to Santiago I then went along and rode the Portuguse to Porto backwards. I have already walked this route 2 years before so knew what I was up for. There is only one major hill I found to be hard and that was out of Baiona. I could have taken the road but again, I wanted to stay on the walkers track and the big climb out of Baiona into the hills was at times needing to walk the bike. However on the way down it was awesome. A bit foggy in the morning but I like to start early so that wasn't too much of a problem. I did come across several pilgrims up on that climb and they were quite stunned to see a cyclist. Once you get down the hill I stopped in Oia where there is a lovely old Monestary and hot a hot chocolate in the little town there. From there on in all the way to Porto I found it easy riding but then I like to ride a lot. Once I arrived into Porto I found a lovely air bnb to stay at for 2 nights until I flew out to Seville and rode the VDLP in 9 days. Lastly theres a great bike shop in Porto and he will pack your bike up for you or service it whatever is needed. The guys name is Felipe and his shop is called "SPORTOURS. Address is Rua do Breiner 412,4050-125 Porto. He is on the website and I totally rate him as the guy to go see. He organised my bike to be packed and couriered to my hotel in Seville while I jumped on a Plane. The bike arrived the same day I arrived. It was perfect.. Anyway hope this helps.
Buen camino....