Hi, I have been working on designing something for a clutch which is pressed by a bellivelle spring. When clutch pedal is pressed, a linkage uses a leverage and works against the bellivelle spring, thus releasing the cluch plates. At this point, I came across a graph that describes the characteristic of the mechanism: As you can see, the mechanism needs totally a different pattern of forces to displace the clutch between new and old. Especially when the clutch is new, the curve is flat at some place and climbs up again. For an old clutch condition there is no flat portion as such and there is a drop of force after a displacement of 12 mm. Can someone pl explain why this happens? Thanks.