How many hours can I expect to get on a set of Bar tires for my BX23? I put a big hole in one of the rear tires and had to get a goodyear bar tire to replace, Kubota dealer had no tires in stock and I needed right away. I now have 2 different tires on the rear, same size but different bar pattern. (Is that a problem?) I was going to get a replacement tire and wheel for the new one and keep the Goodyear for a spare, but I may not want to change just one if nearing age, I have around 80 hours on existing 3 tires.