Red welts from shorts

What the heck! I used these shorts last season,earlier this year and last time I rode I noticed a very angry looking welt on my backside where seam hits me. I used a different pair on Sunday(same brand,similair style) and came back after 79 miles with another welt at a slightly different spot. I am washing everything in woollite as I have done all along. Are the shorts worn out? One season? Am I wearing out? What up...anyone else ever have this? Pearl Isumi brand have been great on my inner self, ya know?
carol

I dunno. For me, I get red welts under the silicon band after a long day in the saddle, but not from seams. Sorry!

looks like you've Stumped the Band with this one.

And you haven't changed your saddle or position lately? How about have you lost weight or lost dimension (firmed up or lost weight)?

Depending upon the short and how many times you've washed them, I have noticed that the seams is where I see the wear on my shorts. Usually due to a break down in the lycra so that the short doesn't fit as snug as it once did and you get friction at the seams.

My current batch of shorts has an average age of about 1.5 years and I'm starting to see problems. However, they weren't a very heavy lycra to start with and I wash in hot water so I expect a shorter life span.

I'd say maybe heat rash that is only occuring at "stress points" like where the seam presses into your skin. How about trying a bit of powder on your skin there when you ride, or some sort of soothing lotion? Has the weather been hotter than usual when this happens?
Try washing the shorts in a mild diluted baby shampoo or something to see if that makes a difference. Sometimes things that don't normally irritate our skin will get irritated under hot sweaty circumstances.

Something similar happened to me a few years ago when I was riding a lot training for an aids ride. All of a sudden, when I took my bike shorts off I would have red welts -- though in my case they were all over my butt and thighs. Didn't hurt, weren't uncomfortable. Hadn't gotten new shorts. Hadn't changed laundry detergent. Just a mystery.

I handled it by taking off my bike shorts as soon as I returned home and got in the shower as soon as possible. The problem seemed to subside when the weather got cooler and hasn't happened since.

Could be just the type of ride you did? I had a pair of shorts last year that were fine for shorter and dry rides, but put them on for a long ride or a wet one and they'd lacerate my poor backside.... something about the stitching on the chamois acted like a little saw blade - left the darndest marks on my hienie - looked like I'd been bitten by a shark and it was none too comfortable either. Slathering the stitching up with chamios butter didn't help either.

Thanks for comments. I am somewhat surprised that this seems to be a rather unheard of malady. I think I may have started this process by going riding,sweating a great deal, getting distracted by chores and not changing asap when I came in the first time. However, I felt the second batch of welts forming(worst on my left cheek) part way into the 79 mi ride on Sunday. I am speculating it was partly the sweat and partly me pedaling weird on that side? Maybe? anyway I could defineitely feel the welts(looks like I was scratched or whipped??) when I rode today. It is where butt and seat collide. Different shorts and lots of butter before I started. Did 40 with 2000' climbing and no new welts. Today was hotter than blazes in Pa. If I discover the root cause, I'll post again. thanks

Another thing I got recently which might apply to you:

About a month ago, it was quite cool and very sunny one day when we were going for a long 50 mile ride.
So I put some knee length Terry knickers on with a very thin chamois, then I pulled some regular bike shorts on over that to give myself enough padding for the ride. The knickers ended at the knee, the shorts ended half way down my thigh. I put sunscreen on my exposed legs below the knee.
After the 5 hour ride, took off clothes and saw a big red raised rash on the tops of my thighs- but the rash ended abruptly right at the line where the shorts started. No rash at all underneath the double layer. I decided the rash was a sun allergy reaction under the knickers, right where I got the most sun, on the tops of my thighs. I didn't really sunburn through the fabric, but the sun + fabric caused a rash reaction somehow. I put hydrocortisone cream on it and it faded after a couple of days. It flared up again a bit when I went in the sun with just shorts on a few days later. Now it seems to be all gone. But as a precaution for a while, I put a bit of sunscreen on that area of my legs, under my knickers when I was going for really long rides. Don't seem to have the problem now.