David -
I found my five-speed/clutch seemed to be getting a little worse at the 2,000 - 3,000 mile point... turned out the clutch cable had stretched a tad, and the black plastic/nylon grit from the primary tension adjuster had kind of dirtied up the clutch plates. I adjusted the clutch cable to zero slack (but not tight), and rinsed the primary case and clutch basket out with kerosene. Changed the gearbox oil, too. Put her back together and its been fine since. Guess I like the smell of the different oils... even the pungent gearbox oil... Now, when I change engine oil every 2,000 miles I change the primary and gearbox oil too. By the way, the black grit from the primary tension adjuster went way down after the first flush. Haven't really had to tighten the primary much, either. Just like most things on my bike, I had to keep adjusting everything for the first couple thousand, then everything seemed to find a place it likes...
Mike and Stumpy in Michigan