I am thinking maybe the clutch now. That seems like an expensive or complex fix.

 

I don't know what the 250 has, but on the 650 there is a shifter return spring that I broke. Caused the bike to not shift properly. If I remember right I might have been able to shift up, but not down. I had to lift the shifter to click into position to downshift. Kinda weird. The spring that brought the shift mechanism back to index the next gear broke after 45,000 miles! You could actually see where the spring had slowly cracked and split, likely starting from a small stress riser.

 

Nah pretty easy, just takes patience and a manual or video.... here this might give you an idea.