From a time ago I noticed that all my cycling bibs padding sewing were breaking at the same place.

The last couple of years I gained a bit of weight. I'm not overweight, as I'm at 75kg and I'm 1.78m tall, but it seems this causes my legs to widen slightly and they rub on the saddle rails, breaking the threads that hold the bib padding. It's happening on both sides.

It's a really slight rub, as I can't feel it when pedalling, and it doesn't cause any issues even on long rides, but it's enough to break the threads, wear the black coating on the rails, and eventually, wear the lycra causing a hole.

I have several bikes and used several saddles and have the same issue on all of them. Currently, my most used bike, which has a Fizik Antares R3 Large saddle has the black coating of the rails partially worn. My old MTB, with a cheap selle Italia had the rails totally polished. My current MTB, with a Canyon saddle doesn't show wear yet as it's quite new, but I can see the rubbing is there.

I'm not worried about the rails finish, as that's purely cosmetic, but I'd like to avoid breaking all my bibs in a short time as they're quite expensive.

Has anyone encountered a similar issue?