@ Machka- 1200K?!!! You're an animal! How long did that take, and what kind of terrain did you cover?
I just got back into cycling 17 months ago after a 12-year break. (I'm 62, and recently involuntarily retired, so I have lots of time to ride).
The reason I posted the original question is that I've noticed a turning point at around 90-95 miles. Training rides of 75-80 miles are now fairly commonplace, and I don't do much to prepare for them other than make sure the bike's in order, but the five century+ rides I've done so far just seemed to be more serious, somehow, and I suspected it was "all in my head" as an earlier poster suggested. I hope that is so, as the mind is more flexible than the body at my age.
For those of you, like Machka, who have obviously shattered the century barrier, are there other distances at which you feel you cross psychological barriers?
And one more question: 95% of my riding is solo, including the centuries I have done and most training rides. I truly enjoy the solitude and the quiet, and the chance to silence the "Monkey Mind", as our Zen brothers call it. How much does a riding companion contribute to your ability to push your limits? I guess I'm asking about psychological support here, and not elements of safety or shared supplies and so on.
Sorry this was so long. Still raining here. Bad case of cabin fever...