Shifter Jammed

I tried searching the forum but keep getting directed to transmission or linkage problems. I believe my issue is the shifter itself.

06 Grizzly 660 – It wouldn’t shift in to reverse or park. I disconnected the linkage and pulled to the shift shaft cover off – I am able to shift through all gears by hand. With the linkage still disconnected, the shifter itself still won’t physically engage in the reverse or park slots.

I plan to pull the shifter assembly off tomorrow and inspect it.

Here is the kicker – I have a 2nd identical parts bike and it has the same issue. Am I missing something, or could they just be plugged up and dirty? Any insight?

Thanks!