Thanks for the PM. Glad to see your a stand up guy, just with a slight ornery streak
The smell and louder sound is hopefully just because you worried there might be a problem and paying a lot more attention than normal
The Z' shifting issue is mostly from lazy shifting and more off the bikes fault than the rider, even when most will feel their clickin it in good enough.
Only seen the 1 back out gear tension screw today. otherwise I've seen no posts on actual gear box problems since the initial release of the bike.
Not that yours might have a real problem.
The ergonomics of the peg to shifter and the stock position are more of the problem.
The ERGO fix is remove the shiftier a clock it down one spline.
Your foot on the peg will travel a lot further down than it will up
do the hyme joint linkage so you can set it exactly where it needs to be for your natural riding position and foot ergos
And full synthetic oil seems to help the shifting a lot from those that post it and say it all but went away after switching.
I would doubt the dealer put in synthetic oil
Loose Engine mount bolts dont help .
I'm sure you seen all the post about the rear/lower bolt being loose
Check chain slack. if you have the stock chain it needs tighten every 500 miles almost.
If clutch lever has 1/8" slack at the lever should be all good there
dont even need to use the clutch as long as you let up on the throttle while shifting.
4 easy maybes before digging into the engine.