Stupid, Stipid, Stupid! That's all I can say about myself.
Last Summer I replaced a 20" front tire on my now commuter and had some issues with the tube. The tire was a spare that came with the bike which I had just purchased used, and I just re-used the old tube that was already on the bike in the old worn tire. I didn't pay much attention to the tire and tube as I tore the front wheel down, it's a pretty boring task as a rule.
Putting the old tube into the replacement tire got a little tricky. The tube seemed to be a touch too big around. I just stuffed it in as best as I could, intending to get fresh tubes in the near future. I had assumed the tube was old and had stretched. Well, I forgot all about it and was gently reminded of my lax maintainance practices at about 10mph with a rapid de-pressurization of the front tire today. When I took the tube out of the tire and saw it folded over on itself I remembered what I had forgotten all about...getting fresh tubes. It had failed at the folded over part.
Now in all fairness, it wasn't the tubes fault and it probably wouldn't have failed if I knew then what I learned over the past winter...all 20" tires are not created equal. I was stuffing a 451 tube into a 406 tire!
As soon as I learned the difference I remembered the front tire and tube stuffing incident of the past Summer and made a mental note to rectify the situation when the weather broke but again, once Spring arrived I had forgotten all about that tube & tire.
I was quite lucky that the tube failed when it did, near home and at low speed. Three days ago I was up around 30mph and 15 miles from home at 06:00 am. I'm glad it didn't fail then as I had no spares or pump with me that time, and at that speed I probably would still be recovering from the fall!
Another lesson learned, the easy way this time. No scars to show off.