Tightening the cable decreases the pedal travel before the clutch disenagages.
I like to have the clutch completely disengaged and still have about 1.5” travel left before the pedal hits the floor. If I shift only when the pedal hits the floor, there are several milliseconds that the clutch disk is not being driven by the engine. In theory, this lets the disk speed equalize and makes less work for the synchronizers – keep in mind that this is a theory, but it seems reasonable. This means that I have only about 1” of free play at the top before the pedal starts to disengage the clutch. Keep in mind that these figures are all approximate. When properly adjusted, there will not be any slack in the clutch cable. You will have 4-15 lbs preload on the clutch cable.
The binding common to adjustable cables is often due to misplacement of the adjusting nuts on the fork end of the cable. This will also cause the cable to wear and fray. Both nuts should be on the back side of the fork so that the domed nut faces the fork and the other nut serves as jam or locknut to the domed nut.
