I just put the new Yoko ES100's on my 83SC.
I had been running the Bridgestone RE730's, I went through two sets of the 730's and was pretty happy with them, no problems at all, just a bit on the short life span side, about 15,000 on the fronts,but really good performance. The Yoko's are better and cheaper, too soon to tell on the life span but every bit as good on the ride and performance and for less money! It is the cornering that I notice the improvement, they really stick, it seems like a tad stiffer sidewall, I love'em !