Hi Beammeup, I'm not sure what this term 'clamping force' refers to....the operation of the cutter clutch is fairly straight forward...the clutch cone is moved by the forked lever and thrust pad inward to dis-engage and released to engage... you can adjust it by the bolt and locknut underneath the cutter clutch handle.. it adjusts the throw through the forked lever by contacting the clutch lever so as it 'over-centres', the clutch dis-engages.
If the clutch cone has fully traveled to its
outer-most position (fully engaged) and is still slipping...the clutch cork lining is cactus and must be replaced. No amount of moving the position of clutch to engine distance, will rectify the problem.
