I bought a brand-new gravel bike that came with stock “WTB ST i23 TCS Tubeless Ready rims - Formula Cartridge bearing hubs” (700c, 28 spokes) wheel set.

I have been riding the bike for nearly 2 months / 800 miles now and I have had three spokes on the rear wheel break (2 originals + 1 replacement re-break). All broken spokes have all snapped near the hub. I have been periodically checking spoke tension between rides and have noticed loose spokes many times, which I have retightened and separately re-trued the wheel (which can still be made very respectably true).

What is happening here? 1 broken spoke might have been a fluke, but 3 spokes in such a short time leads me to believe something else is going on. I am only having this problem with spokes on the rear wheel; the front wheel has been perfect for the (as yet short) life of the bike.

My best hypothesis at the moment is that this wheel is just too weak for my use case. I am not personally that heavy (if anything, I’m light), but I will carry groceries in my rear panniers though nothing crazy heavy as of yet. This has never been a problem for me before, using my old bike (32 spoke wheels). The road quality is decent and I have been staying near the recommended tire pressure (silca.cc calculator).