Cycling and Comfort: When Does It Hurt?

Small confession: For the past couple of days, I have been using my road bike for transportation. Not out of choice, but out of necessity - I can't spend more than 2 minutes on any of my upright or semi-upright bicycles right now without pain.

In my excitement about Marianne's conversion, I took her on her longest ride yet as a fixed gear - 28 miles. For the first 20 miles, everything was fine. The bike's geometry has never been the most comfortable, but as a fixed gear it felt better than ever and I was pedaling happily. But then, with just 8 miles to go, I suddenly became aware of a rapidly growing discomfort - not just in one area, but in several: in my shoulders, arms, back, pelvis, joints - pain seemed to be everywhere and it attacked me all at once. By the time I got home, I felt as if I had been run over by a train. I took some Ibuprofen and expected it would go away in the morning. But when I tried to ride my vintage Raleigh the next day, I felt the same pain immediately and barely managed to cycle to my destination a mere mile from home.

Mysteriously, I can still ride my roadbike with zero of the pain I experience on the upright bikes. Somehow being in the drop-bar position on the comfortable Rivendell does not activate any of the same discomfort. So, I am now in the ironic situation where I can go for 35 mile rides on a roadbike, but can't cycle for even a couple of miles on any of my city bicycles. Argh!

My working hypothesis of what happened is that while riding Marianne, my legs grew tired of the fixed gear pedaling, and without realising it I began to put more stress on my arms, hands, butt, and everything else. And because the mixte is semi-upright, this damaged some joints in a way that the pain only shows up in the upright position, but not in a leaned-over position. Does that make any sense as a possibility?

But this particular situation aside, I have been thinking a lot lately about comfort, and, more specifically, about when it is appropriate to declare that a bicycle is "comfortable".  Had I limited my rides on Marianne to 20 miles at a time or less, I would have thought she was perfectly comfortable. I could have ridden her this way for years, thinking that I had a comfortable bike - but I would have been wrong. And that is why it is so difficult to determine a bicycle's comfort based on the sort of test rides you take at the bike shop, or even short rides on your own. Bicycle A might feel better than Bicycle B after a short spin, but how will they compare after mile 20? mile 50? mile 100? You just do not know, until you actually ride the bicycle for that distance.