Recovery rides (or runs if you are into running) will almost certainly form a big part of your training program regardless of what goal you are working towards. It's impossible to go full gas all day every day and your body needs time to recover. Here are my thoughts on how fast/hard these rides should be.
If you have a power meter then it will definitely help you to pace these rides correctly. I don't so I just ride to feel.
I try and keep these rides conversational pace the whole way through.
When I'm done I want to feel as though I can do the whole ride again at that same pace without a problem.
I talk more about all this in detail in the video.