[antonye]

Do you know what piston diameter the clutch slave is?

To get a lighter action the piston is bigger than the oem size BUT to push the same amount of fluid and move the clutch push rod the same distance will mean that you will have to pull the lever further. This is the trade off.

Have you tried setting the span adjuster so the lever is all the way out?

The other thing you could do is to wind out the barrel adjust slightly - the bit that pushes into the master cylinder - but be careful not to do it too much otherwise it will drag the clutch.