BMW F650 Funduro clutch slipping after one year

I had the clutch kit put in a year ago and am experiencing the same symptoms. I normally only take the bike up to 4000rpm and travel at 100km/h. I rarely ever go into the 6000rpm territory but almost a year down the line after the clutch was replaced I thought I would give the bike berries and as soon as it hits 6000rpm the clutch starts slipping all the way up to 7000rpm which is short of the maximum rpm. Now I know that they even replaced the springs in the clutch and I am puzzled that a clutch can only last 10000km. What do you think could be the problem besides adding friction modifiers to my oil which I have not done? The oil used was what BMW normally use to service a bike. Any body got any ideas?