Probably "Period Correct" rather than like the original tires are the new K81/TT100 Dunlop tires. They come in two compounds, the GT spec. is a modern sport compound tire, and they come in correct 19" and 18" sizes. The distinctive tread-pattern was the tire to have, back then, and they suit older bikes for looks - I'll always use the softest tire I can find, for obvious Safety reasons! A lot of guys use the Bridgestone BT-45 series tires, which are good modern rubber. The K70's were always a "work a day" tire, don't know if they make them in a modern type compound! K87's bob up on E-bay every now and again, but I wouldn't be using a 40 year-old tire, regardless - even tho I used to race on them, back in the '70's!!
