Does this look like a defect to you?

[DAVINCI]

It does to me. This Bridgestone S11 tire was manufactured 47th week of 09, installed April of '10. So it's been on the bike for a year, 4000 mi on it. The split isn't all the way through, so it didn't lose any air. But it could have been a lot worse if I hadn't discovered it and it decided to blow at speed.

Check you tires, boys before and after every ride.

[xsroadrunner]

Hard to tell if its a defect or something you ran over.

[fredintoon]

It does to me. - - -

Hi DaVinci,
yeah, me too. Or you could have run over something sharp?
Whatever, you shouldn't be riding on it and you'd best put another tire on there.
The only difference is, who pays? If it's a defect, the tire supplier should pony up for at least the unworn portion, if you ran over a sharpie you are stuck buying the replacement yourself.

[DAVINCI]

New tire is already installed. I think it's a defect 'cause the split seems to follow the contour of the tread.

[Elevener]

Yeah. looks like defect. Also looks like you prefer right turns.

[James England]

You'd get something like this from a curved piece of broken bottle, I reckon......

[DGXSER]

99% it is a defect. It would take a really rare and odd object to hit the tire just right to make a cut that follows the groove of the tire like that. Not impossible but extremely improbable.

[James England]

Don't defects tend to be a slightly ragged tear, rather than have a sharp edge like the one in the pic.? A bit like the ones you get on a really old tyre that's split.