Remember reading a article in Cycle world or Motorcyclist years ago on how to improve on the KZ650..... they liked Bel-ray 15 weight and I've always stuck with that........ I'm willing to bet I couldn't tell which was used in a blind test 10-12.5 or 15.....so like said use what you feel good about and trust.
1978 KZ650 b-2
700cc Wiseco kit 10 to 1.
1980 KZ750 cam, ape springs, stock clutch/ Barnett springs.
Vance and Hines Header w/ comp baffle and Ape pods, Dyna S and green coils, copper wires.
29MM smooth bores W/ 17.5 pilots, 0-6s and 117.5 main
16/42 gearing X ring chain and alum rear JT sprocket.
