Try adjusting the clutch this way, but first ensure the Clutch lever pivot hole is not worn before adjusting the clutch and cable is not frayed causing the elongation of the cable
They can fray at the handle bar or inside the sprocket cover. Take off the sprocket cover and check it
Now,
Screw in the cable adjuster full at the lever end.Remove the rubber bung on the sprocket cover
Loosen the lock nut with a deep good quality ring spanner or as Disordlypunk says a 6 sided socket to loosen the locknut ( it will loosen with a crack and frighten the crap out of you)
Turn the lock nut anti clockwise a full turn
Hold you fingers lightly on the clutch lever
Turn the centre screw clockwise with a good fitting flat screwdriver
You will feel the lever moving out
Keep turning the screw until the lever is about 5 to 6mm from the lever housing.
Tighten the locknut.
Replace the rubber bung
Take the final adjustments at the cable adjuster
If you cannot get less than 10mm at the lever or the adjuster screw tightens replace the cable
They can fray at the handle bar or inside the sprocket cover. Take off the sprocket cover and check it
Now,
Screw in the cable adjuster full at the lever end.Remove the rubber bung on the sprocket cover
Loosen the lock nut with a deep good quality ring spanner or as Disordlypunk says a 6 sided socket to loosen the locknut ( it will loosen with a crack and frighten the crap out of you)
Turn the lock nut anti clockwise a full turn
Hold you fingers lightly on the clutch lever
Turn the centre screw clockwise with a good fitting flat screwdriver
You will feel the lever moving out
Keep turning the screw until the lever is about 5 to 6mm from the lever housing.
Tighten the locknut.
Replace the rubber bung
Take the final adjustments at the cable adjuster
If you cannot get less than 10mm at the lever or the adjuster screw tightens replace the cable