In Reply to: Re: Comment on sport clutch... posted by ADA///M on August 14, 2001 at 09:12:27:
HD clutches either come with a full serface friction disk or a "puck disk" The differance between a "normal" full surface disk and a HD one is that a HD one has a bonding agent (glue) as well as the rivets you see on a normal disk. A "puck disk" has a non-continuous friction serface (a three and a four puck example are in the picture). If there are even tiny irregularities in the surface of your flywheel where the clutch disk makes contact (friction serface), you will have a very uneaven grab when you engage the clutch. A machine shop can dress the friction serface on your flywheel to remove runout. Aluminum fly wheels have a steel disk bolted on to them for the friction surface.