First time poster. I have a 97 HD Fayboy with the Evo 80 ci and 5 speed trans. Here is what is going on. We just changed the secondary drive belt from stock HD 130 rib to a BDL 130 rib due to squealing issues. The bike has 18K miles. After replacing the belt we changed clutches and pressure spring also. New seals on the inner primary and fresh fluids and gaskets. Yes we soaked the friction discs. After adjusting the primary chain and the new belt and clutch I took it out for a break in ride. Smooth shifts and easy take offs. On the second ride I had my wife on the back and as we left the light it felt as though the belt jumped a tooth. Or the primary chain slipped. If you know the feeling of a slip you know what I felt. This only happened while under medium torque. We immediately went back into the primary and adjusted and checked everything again. Even changed back to the old clutch plates and spring. New fluid again. We did tighten the secondary belt adjustment by just a little. I took the bike out and did a more aggressive take off and no slippage. But that did not last long. It makes a clunking sound when this happens. I an stumped and could really use some advice. I have never had this happen before and the bike was not doing this before we tore into it. Help please. Thank you Rick C.