Wow; that looks just like the K70 tire from my BSA. I used a K87 and K91 on the Kawasaki rear; they wore like iron but didn't provide the same traction as later tires. I'm using Pirelli Sport Demons now and they work well. I read that Bridgestone Battlax also work well. Ed
1977 KZ650-C1 Original Owner - Stock (with additional invisible FIAMM horn)