None of the above, really.
- Unfixable mechanical
- Illness or random fatigue
- Heat stroke
Stuff that might happen a few times per year. Except the unfixable mechanical; I don't even recall when I last had a serious problem. A rim cracked in 2014 or 2015 and chewed through both my spare tubes, and when I took a closer look it was clear I wasn't going to ride anywhere on that wheel. (Curiously, that might have been okay with tubeless today.)
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