Good viewpoints from all. FJRs are notorious tire eaters. I ride mostly Northern Rockies twisties but some flat stuff occasionally, almost always two-up and loaded. Yes, the paving and ambient temperatures will be a major factor in tire life. Chip seal chews them up, as does 95 degrees. The BT023 rear I tried barely went 4,000 miles, running 40-42 psi. On the other hand, the best I've ever gotten from any rear was a PR3 - 6,500 miles and leaking air through the exposed cords. Currently trying to wear out a set of Pirelli Angel GTs. These, IMHO, are the best tires I've ever run. Currently at 5,900 on the rear with 1,000 left, maybe more. They feel wonderful and the bike seems to have shed 50-100 pounds. Handling has not deteriorated with miles, as I've seen with the Michelins. Given all that, I would spoon on brand new rubber before departure; then you'll have no worries. Keep the OEMs and run them out later. Too many times I have left on a trip confident I had plenty of tread, only to be searching for a shop with the right tire and paying full retail plus mount & balance.