Originally Posted by
KraneXL
As am I by yours. Even with frequent in-saddle/out-of-saddle breaks there is still a "bum soreness limit" to how long you can ride in one session. That is the question.
Actually, no there's not. Your personal experience is not law, it's just what you've experienced. 400k is not an issue. I was happy to stop on one of those, but that's partly because of the 15,000' and partly because I was pacing for 400k, not a longer ride. My butt wasn't sore in any case. I also make it a point to try to stand every 10 minutes. That helps a lot, as does stopping for a bathroom break and a water and snack refill about every 50 miles. it's certainly possible to stay on the bike for longer if one is riding supported and can pee from the saddle.
That said, I think your definition of "one session" might be idiosyncratic, that is, it means what you want it to mean..
In any case, the more miles one consistently rides per week, the longer one can stay in the saddle, providing that one has a good pair of shorts and the right saddle for one's butt. It's conditioning, like anything else. My guess is that the OP has not yet found their dream saddle.