Shoot for 8-10 hrs/day in the saddle IMO. Miles are less important than hrs. Typically that will be about 300-500 miles.
A 400 mile day for several days is easily done and still enjoyable. A 600 mile day for several days will wear on you...rather quickly. Remember too, it's not really about how fast/long you go. What will kill your progress is how fast/long you stop. If you take 30 minutes for a pee-break several times a day, your day's progress is shot in the foot.How many miles can you reasonably run per day on a trip and still enjoy life?
I'm leaning toward 400-600 depending on the road/weather for extended days. I don't want to over do it and end up making it a test of will ya know?
I know peeps do a ton more on 1-2 day trips but i'm thinking about sustained riding. Say 7+ days in a row.
I know there are ton of guys running long trips on here so I'm curious what you aim for when doing routes.