Had to change my rear roadtec Z8 yesterday as I noticed the tread was down to the wire, but only in the center, I have seen this before but on Pirelli angels. These tyres have lasted well, I changed the front a short while ago because they were developing a 45 degree chamfer, more on the right than the left but still had plenty of tread n the middle, now I've had to change the rear due to the middle wearing right down but leaving plenty of tread on both sides. I think this must be down to pressures so am considering lowering the pressure at both ends by 2 lbs. I keep a close eye on the pressures and have run these tyres at 36/42 from new. Has anyone else experienced wear like this and what did you do to cure it?