Originally Posted by gregm
How can an old tube in a new tire cause a pinch flat? A pinch flat is normally due to a (relatively) under-inflated tire striking a pothole or some other object very hard, so that the tube folds and is smashed against the edge of the rim. (Ouch!)
Sounds as if the culprit (piece of glass? staple? nail?) was not removed from the tire casing before you repaired it the first time. Did you reference the leak's position against the tire, and find where it was compromised? Was the second flat in same location (referenced to the tire) as the first flat? I always locate the casing hole, or the offending object, as part of every flat repair.
-Greg, who has had well over a dozen flats so far in 2006, most due to glass!
Tandem riders more experienced than me called it a "pinch flat", said I need to put talcum powder on the tube before I install it. 2nd and 3rd appear to be caused by delamination between the rubber casing and wire bead. I'll show it to the mechanic before I claim it defective or caused by "operator error" from improper installation. I had to use a tire tool to get both new tires on. I've done it before and never damaged one.