I am rebuilding the clutch on my cb500. In my manual there are 7 friction discs and 6 clutch plate b. There is also a clutch plate c and a spacer. Well every time I put this extra one in the clutch does not engage. It works perfectly without this disc and shifts great. I am just wondering if I need this disc in the basket? Also when I bought it from the owner and took it apart he also did not have a disc c or spacer. The clutch like I said works great without the disc c and the spacer but with it in I cant even get any movement with the clutch engaged. Help please