I'm thinking about biking from San Fransisco to Pittsburgh this summer and was wondering how long it would take? Is it possible to do 100miles a day for the entire time?
# of days - All depends on what you're comfortable with riding on a daily basis. Answer that first.
100 miles every day. Unless you're a very experienced and strong bicyclist with support along the way, 100 miles every riding day is probably unreasonable.
Good luck... it can be done!