The
Brierly books are a good source. I rode the
camino frances last month. I rode from St. Jean Pied de Port, France all the way to Santiago. About 500 miles and I completed this in two weeks.
A couple random comments:
The
Brierly Books were published a few years back. In the interim, Spain has this interesting habit of renumbering or reclassifying some of the major routes. If, when you arrive the route is signed as 'N' (national), then you will be okay. If the route is now signed as AP (AutoPista) it means that the road is now a tollway and bikes, horses, and farm implements are prohibited.
A mountain bike, trail bike, comfort bike, or cyclocross is a good choice as this allows you to ride on either the roads or on the camino path. There are many sections of the camino path that are just too rocky and where you wouldn't want to ride a bike. Usually, the road section is not very far from the camino path.
I took my bike over and transported it in a bike box. This created a whole series of issues for me that were travel related but did not apply to the camino. You'll have to plan where to store your box and then when and how you will retrieve the bike box. If, while in-country, you intend to take either the train or bus, you will need a bike bag (ALSA bus company sells these) as this will allow you to transport your disassembled bike on the bus or train. If I had it all to do over again, I would have rented a bike - less costly and less hassle.
Many of the guide books related to cycling will point out which towns include bike shops. Bike shops are closed on Sundays and many retail shops don't open until 10 am and most close during the lunch hours. I must have ridden by 10 bike shops on my camino and only two of them were open at the time of my travels. If you take your own bike, bring along some extra spokes. You can zip-tie these to your front fork.
I had read that many of the Albergues defer on cyclists seeking acomodations so that the walking pilgrims could have first choice. I didn't find this to be the case when I was on the camino. Many of the albergues also have a safe storage area for your bike.
You will likely find if you are riding, that you spend much more time on the road than on the trail. I found that the drivers in Spain generally respect cyclists and afford them a wide berth on the highways.
While the walking pilgrims like to leave before daylight, to avoid the afternoon heat, cyclists should wait until almost daybreak, especially if their route includes road travel. While you are likely to come across other cyclists on your journey, in many respects cycling the camino is more solitary than walking the camino since there are fewer of you.
Your smart phone can be outfitted with sim cards in Spain for your trip or you can make arrangements with your wireless carrier before departing. This provides access to weather and current road layout. All of the Albergues where I stayed offered wi-fi, as do the hotels, cafes & bars. This doesn't mean they always work for you so you have to be prepared to take this in stride.
not only is it important to be in relatively good shape for cycling, you should plan a couple of days of riding prior to your departure loaded down with all the gear you intend to carry and WHERE YOU RIDE SOME BIG, LONG, NASTY HILLS. This will provide a good barometer of your overall fitness and where you can make decisions as to what you really need to carry on your journey. I brought a cheap sleeping bag as I was concerned about bed bugs in the albergues but found that this wasn't really necessary so I pitched it early in my travel.
In and around the smaller towns and in your albergue, you can generally feel some level of safety regarding your belongings. When you are in the big cities, there are pickpockets and it would be terrible to lose your bike or panniers mid-way through your journey. I brought along a lock & very thin chain for intended use in the big cities.
And here's the relevant bit of the blog... 
