I don't know what my limit is for an individual daily ride -- the most I've ridden in a day is 155 miles, which was this summer, and I felt pretty good at the end. I think maybe next summer I'll try to do a double century and then say that's enough. I toyed with the idea of riding brevets w/the randoneering club but there comes a point when their rides involve long rides at night over highways, and that I'd rather not do.

In terms of getting miles in, I think I ride enough. There are days when I can't ride due to work or family obligations, but once I worked commuting by bike into my schedule I manage to get plenty of miles. However I don't always have time to do the longer rides I'd like to do -- I rode only 2 centuries this year; I think 1 or 2 more would have been ideal for me. I do get bored on a bike after about 80 miles or so if I'm not riding somewhere really nice or trying to chalk up a particular challenge.