big john

In 1987 I had a front wheel collapse when the rider behind me touched my rear wheel. This pitched me slightly sideways and the wheel just bent in half sending me into the pavement.
A few years ago I was riding Ksyrium wheels and a spoke ripped out of the rim. These were the wheels where the nipples thread into the rim. I limped it along until 2 more ripped out and then I couldn't even push it. I walked a couple miles carrying the bike until someone called a cab for me.

Twice I have seen the brake track blow off of a rim on the road. Once I saw a hub split open and a spoke pulled out of the hub. On my bikes I have had sections of the rim pull away from the brake tracks.

I never raced track but I have seen wheels collapse under men and women on the velodrome.

These are just the first ones that I remember when I read your post.