I did basically the same thing, run "double D's" in my RSV for the last 35,000 miles with the original clutch discs installed. It started slipping at about 45,000 miles so I put in an old diaphragm spring that came out of my Vmax when it started to slip. Everthing else was left like it was and haven't had any slippage since. The bike currently has about 80,000 miles on it now. The extra diapragm spring takes a little getting use to, but like Earl told me back then, "soon you'll be able to crack walnuts with your left hand". HaHaHa