After thinking i only have 1.5mm left before i hit the wear bar on my tyre, I've found out what i thought was the wear bar is actually part of the tread the wear bar has TWI written on it but i needed to put my specs on to see it the first picture is what i thought was the wear bar The 2nd pic shows the actual wear bar with TWI on it. Yahoo! got 4.5mm left.. I'm not a hooligan after all
That will be there for stabilisation between the tread on such a large tyre. Also gives extra grip as the tyre is worn down. Glad you got your specs on and figured it out!