Under hard acceleration, I had some 'slippage' somewhere in the transmission, that lasted for fraction of a second;

...engages then slips, engages then slips, several times,and only occurring in second gear.

After ruling out clutch,  I decided to pull and inspect the drive shaft, and sure enough worn shift forks and gears.

Works good now!

After having some trouble starting at times, I decided it was past time to check fuel filters.

These are worse off than I would have expected, though the bike has 38,000 miles at this point.

Did seem to rev a little quickly while riding under heavy acceleration. Replaced steels, fibers, and springs.