Looking at my almost new conti GP 4000 today on the rear wheel and it appears to have a a couple of perfectly round 'holes' in the tread. Don't look lie gouges, don't know what caused them or whether they are manufacturing defect?
Tyre stays up fine, its not through the casing, but they are quite deep. Safe to ride, or risking death at hands of a high speed blowout?
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ta
Wear markers. When they are gone replace the tyre.
Are they tyre wear indicators? When they are no-longer visible, replace the tyre. (Just a guess, but look like they're meant to be there).
Edit - Wot he said ^^^^
Doh....yep just checked and they are on the front as well!
Mods please delete before I become a laughing stock...
Too late
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Do you have any headset questions you'd like answering while we're at it?