From a cold engine, let it warm up (under idle, not revving the eng at all) to 4 bars.Shut it off, and check the oil (dipstick).
Make sure the bike is standing centered.
I would run some Seafoam (injector/carb cleaner) thru the tank to see if it clears up any hesitation problems that are occuring.
"Be of good cheer. All may yet be well. There's many a fork, I think, in the road from here to destruction."