Have had a few problems with rough shifting on this bike. Pulled out the manual shift bar just to listen and feel as I used my hand to shift. Shifting is happening but it's rough and sticky. In other words if I manually shift from N to 1st by pressing down on the manual shift bar, then let go of the bar, the spring return (which would cause the shift bar to return to it's original position) is very slow.

Any ideas? I haven't changed transmission fluids but the bike only has maybe 15 hours on it. Any help appreciated.