recurring UTIs

[Crankin]

I would also consider the saddle/shorts combo. You have to get both right. I had constant pressure, an increase in UTIs, and an actual lesion in the soft tissue from a saddle that I thought was great, but wasn't. When my doctor was puzzled about the lesion (she said "it's not cancer, but I can't figure it out"), I knew immediately it was cycling related. When I got the saddle I have now, I was skeptical, as the weight was much more on my sit bones, which took about 2 weeks to get used to. The LBS owner/fitter told me my butt would hurt, but eventually I would get used to it, and he was right. I have had no burning, pressure, or any other discomfort since. It took me 8-9 years after the lesion to make this change, so I was used to having issues all of the time.
I recently got a pair of Terry Chill shorts. They have the "light Flex Air" chamois. I do not like too much padding, and while I wouldn't use this for a longer ride (40-50 miles+), it's more than a tri chamois, so you might find this to be happy medium. They are expensive, though.

[north woods gal]

Couldn't agree on the saddle part of the equation. I switched to the wide old lady comfort style saddles for my snow biking, this last winter, because it is essential to get planted on the seat, instantly and perfectly, as you hit the pedals to get rolling in the snow. That's when I discovered just how wide my sit bones really are and how all my life I had been riding saddles too narrow. I'm a big gal, anyway and now I'm also an old gal, if that has anything to do with it, but if you're saddle is not properly supporting your sit bones, you are setting yourself up for all kinds of issues, not just UTIs. Then, too, if your saddle is too narrow for your sit bones, you are not getting the max leverage out of your legs when you pedal. Only problem I have, now is finding a wide enough saddle in a performance saddle, instead of the big clunky comfort saddles. Wide AND light is a tough combination to find.

[antimony]

Yeah, the thing is, I've ridden this distance (400k) in these shorts with this saddle several times and been fine; on this ride I felt pretty bad fairly early on -- like less than 100k in, when that's a distance I do in this setup all the time. Part of the issue is it's not an every-time thing, so I'm not sure what all the factors in play are. Like, this is a three times in 5 years of randonneuring thing, but this time it derailed a ride I was really excited about.

Saddle is definitely under my sit bones, and is generally really comfortable, and my shorts all have the Terry flex air or fleet air, which I think is plenty or even more padding than I need -- my tri-shorts are literally just some fleece, and that's OK for 125 miles, but not more. I'm thinking maybe I should try the Desoto 400 mile shorts, which are a 4mm pad, but they're $160, which is a lot for an experiment.