I have a 1973 250 SuperSport ‘egg’ engine bike.
The shifter would tend to ‘stick’ in the higher gears, it would stay down and not return. Spring felt good.

I popped off the clutch cover, clutch and hub so I could inspect.
Turns out the bushing that the shift shaft (desmodronic assymbly in the manual I think) had some groves/wear in the lower part. It appears to be brass.
So I speculate it would tend to jam a bit, although I would think the outer case would keep if from moving much. But obvisouly it has not. Someone has been in there before (super low mile bike) and it had the issue when I got it. So I suspect someone saw it and gave up.

anyone know if that bushing is assembled from the inside? It appears so in the manual, but it is not clear.
alternately I could perhaps put a small shim to keep it flat, and use a smaller shim on the outer end- adjusting to give some clearance but keep it from moving. ?

Any input?