Originally Posted by
plonz
I'd replace it but I guess it depends on your finances and riding style. Sure you can try the other recommendations and extend its use but I wouldn't risk it if you're hammering high speed turns with your local shop ride.
I've got several 40mph+ downhills on a few of my weekly rides, so I don't screw around and try to get a few extra weeks of life out of an almost dead tire.
I buy tires as cheap as I can on ebay, so I just take the hit and replace stuff like this immediately. A tire is cheaper than my copay!!