Can't remember the codes, but the tire will have a coded manufacturing date. Do some searches and find out the date format for your BT45's. Bridgestones have served me well and I have never seen one do that. I have my second set of Battle Axes on my VTX with close to 10K and they are still in good shape. But some dealers have been known to sell old stock tires well past their usefulness. Tires do not get better with age, they become a dealers loss if he can't unload them. In tires NOS is not good. Check the date.