Bulging tyre

[Candaules]

Half way through my Sunday ride, my rear wheel started bumping. I thought I had a flat, but inspection showed a bulge on one section of the tyre. When I deflated the wheel, the tyre looked normal, but when I removed it, I could see what looked like a worn or perished section on the inside of the bulging section. The smooth rubber suface had given way to bare fibre or fabric. This had weakened the tyre so much that it bulged, even at normal pressure

The tyres have given me good service, though they still hade some life in them, so I don't mind replacing them. However, any thoughts about the cause?
Manufacturing defect? Wear and tear? Damage? Could a careless tube repair have smeared glue on the inside of the tyre? How common is this?

 

[Mr Pig]

Tyres are made of rubber so they perish, they have a finite life. They fail due to time and not just wear. This ones done, time for new ones :0)

 

[TimP]

It's a failure for that tyre. Just be grateful you got life out of it before it went. Why it failed - usually a weak point/manufacturing defect to get a failure like that (unless the tyre really is worn to the canvas). As for the trigger to make it fail - dunno.

I've had a stelvio fail (must have been from a manufacturing defect) for a similar effect with only a couple of hundred miles (tops) on it.

 

[Mr Pig]

As for the trigger to make it fail - dunno.

It usually tells you in the product instructions not to get oil etc onto the rubber. The reason is that it'll soak in and break it up. I'm not saying that's what happened this time but it is one reason rubber can fail.

 

[Globalti]

Check that your rim is even all the way round - if there is a ding, the brakes may have been grabbing at exactly the same spot on each rotation, which will have caused the tyre to wear in exactly the way you describe.

Either that or you've been pulling skids? Or someone else who borrows your bike?

 

[Candaules]

Oil?

Thanks to all.
It may well be oil. I can be a bit heavy-handed with it sometimes.
I've fitted new tyres now, so I hope they'll last.