Comment by jakecodes

I looked up the names for the parts of the fork: It's the part of the fork called the dropout that fails. Here's a picture of a dropout itself: https://i.stack.imgur.com/VZ8bO.jpg, not mine.

When it fails it may look exactly the same (you won't see anything wrong), if you take calipers to it, you'll notice the gap has widened. So measure it now and remeasure every once in a while. If it's changing you've got a problem.

OR you may be able to see it is visibly slightly wider, like more bowl shaped. It doesn't take much for the wheel to come off, it's very tight tolerances. I've never had one snap yet, but I've heard of other's whose dropouts have snapped.

You will notice it is starting to fail when you brake and the wheel feels like it is shifting ever so slightly. It might make a tiny little clink sound. Sometimes it will make the wheel clink around in the dropout when you go over bumps, since the tolerances are SO tight in that area.

It's not just stretching the C towards a straight line that happens, but also twisting at that area or flattening from side to side movement.

Ever since they failed on me a few times I've been riding less because it's a problem I have not solved yet. I reinforced them with 1/4 inch steel. Still it moved independently.

One other solution I've heard about to get bigger tires, they are often called "fat tires". That dampens the stress on the bike a lot. It also makes for a much smoother ride. But I've not done that yet since fat tires need space in the fork. I think a stronger fork and fat tires may totally solve the problem. Fat tires would be nice because it'll turn your bike into a nice smooth ride, and you know how rough the ride can be at that speed for that long.