Right now I have Metzeler Roadtec Z-6 on my K12RS. They have started cupping on both the rear and front. My husband had a set on his R1200RT and they did the same thing. By the way we live in Illinois but we do a lot of riding on curvy road in other states. We trailer the bikes. I have a lot wear left on the tire but when you go into a curve it feels like you have a tar snake with you until you get over on the side of the tire.
Anyone have any suggestion on what type of tire to try next? I use all the tire when I ride on curvy roads. The little elephants have short trunks now.