Hello,
98 boxeye with 44.000miles on the clock.
I think something is not ok with the clutch. When I change gear I have to feather the clutch a lot to have a more "smooth" feeling on the gear train.
It's a very harsh/snappy engagement!
Clutch cable is tuned ok, new transmission, +/-3cm chain slack (almost touching the rubber).
Maybe a outer basket notched?