So just FYI and something that no one seemed to mention on this post is the cable itself. A old clutch cable will become insanely hard to pull in. Other than lubing the cable/ making sure the cable is binding anywhere has it ever been replaced? 2002 was a long time ago now. I have seem this many times and replaced many cables due to hand cramping. The only other problem assuming the adjustments were done correctly can be the clutch basket itself. The clutch plate guides wear grooves in the clutch basket aluminum which makes the clutch plates themselves difficult to move. The only way to check this is to pull the cover off and then take the plates out.