Earlier this month I had a issue with a broken axle. It was the original that was sold with the bike and lasted around 5,000 miles. I went to my LBS and bought a new axle (unbranded, labeled, etc, paid $13, came with cones, spacers, and hardware). I did the install myself and had everything adjusted nicely. The next time I rode it was on my commute to work, but I didn't get 4 miles into it when I found that I bent the axle.
I took the wheel to the shop but they wouldn't do anything about it since I didn't have them do the work. However, I figured this was a fluke and asked them for a new axle and to true the wheel. Once again I did the install of the axle and only got 15 miles out of it this time before bending it. Before I got home I felt the wheel get stiff, but it stayed true.
The question is what will be a cause of bending 2 axles in 20 miles?
I think the guy at the shop said it was a cro-moly axle (while talking to another person today at the shop, these may not be), and he couldn't believe that I bent it. If so, where would such an axle fall in the quality hierarchy?
Or is my hub toast?
While the wheel was being repaired, I swapped to a new original wheel for about 2 weeks. I have not had any issues with it, but I wanted to keep it as new as possible.
Reading other questions I saw a comment that said not to use a hub where the bearing was catching. I did have one in this wheel but I figured since it is a cheap wheel I would just burn it up and move on to a better one. Besides, it has lasted 5k miles without issue to this point.
The bike in question is a 2008 Schwinn High Timber with Joytech freewheel hubs. I do use a trailer with this bike using a Burley axle hitch. While I had the hitch installed on both axles I bent, I did not have either trailer hooked up to them.
Something I would like to note is that when I removed the first bent axle (axle #2) that the cones on it had a wavy bearing track. I didn't think too much of it, and I put them on axle #3. Only having a few miles on them shouldn't have made a difference?