Ya....my clutch does the same thing on my 200, it did it when the OEM plates / springs were in the bike from Roost, and the (sp) Barrert clutch pack was installed several years back. It only does it when it get HOT and I'm WORK'IN the dog snot of of it!!! I am one to not change up my routine much, so I really can't say if it's the oil, or it might be the oil???
Here we go again.....oil.......I used to use Golden Spectro 80wt 2stroke tranny oil and it did it with that oil and it does it with Motul 2 stroke tranny oil as well.
My last 2 rides were killer on the clutch, in fact I abused it more the last 2 times out than I have in the last 9 years......it was chripp'in like the Back Street Boyz
I even had water in my over flow tank......she was HOT!
I don't worry about it, it has made this nosie since I've had the bike.....much like having a bunch of 11mm and 13 mm nuts and bolts...it comes with the program.