This is what happens when a rim explodes. I had the smallest ripple in the rim. Nothing new. I have had blips in the rim a few times. I tend to ride until it gets worse. After this, I might stop with that approach.
The small blip slowly worsened until I had a proper bump. Went out with the bike and wheels to the local shop to explore a replacement rim. I then rolled the bike up the street and locked it to a pole as I went shopping. Came back 30 minutes later and found this.
The pressure of the tire on the rim had created an explosion. The rim was torn to shreds, metal strips of the braking rim itself torn free. The inner tube was destroyed, a crater-long tear.
It must have been an alrighty explosion. I can only be grateful this did not happen as I was riding at speed. Or just riding. Needless to say, the wheel was impossible to ride. I have a new, inexpensive wheel already and the aubergine ride is on the road – an essential ride in this filthy winter weather.