| Could be owt.
Have you had a look at the rear swing arm for signs of ali swarf where the cush drive casings have backed out and are eating the eccentric adjuster?
My 996 felt notchy at the and it was these little devils.
If you think its the clutch whip off the cover and use clutch cleaner spray to get rid off any dust that might have accumulated there, worth a try.
Wheres the juddering from?
Front or rear?
More info the better | 
Hybrid Mode
