[nelly]

You can usually get away without removing the cushdrives.
Remove the big circlip from the back of the carrier assembly and the washer, then tap the sprocket off the carrier.
Grease the cush drives a little.
The Renthal carrier should then slip back on, might need a little tapping to get it to seat correctly. Fit the washer and circlip and you're done.
If you do need to remove the cushdrives, you'll need a 12mm allen key.