Bought my K5 recently. Took it for a test ride, in the buyers neighborhood, just ran it through the gears, and revved it out in gear, all seemed OK.
When I got the bike home. When I ride at 1/4 or so throttle (short shift), up shift, and it shifts into the next gear.
Under power, up shift, and it stays in the gear it's in. With an exaggerated, 2nd up shift, it goes into gear. So with two up shifts, it goes into the next highest gear. No down shift issues.
There is no jumping, in or out of gear, also the shift lever, either, hits, the frame, or almost, when moving the shift lever down, but it does shift down.
I know I have to open it up to be sure. Has any one else had, or seen this happen. Probably the shift arm, at the pawls is bent, or the drum, and pawl system, are worn.
If you have seen this, what did you find?