4th Gear issue '82 Naked

[NuttyERnurse]

Good mornin'!

I'm having an issue with 4th gear in an '82 Naked Goldwing. When riding and shifting to 4th, no strange noises or issues, but when I accelerate after the shift, the clutch lever begins bouncing all over the place, and the engine is spitting and sputtering, like the gear isn't quite in gear or is bouncing. I can ride the bike, higher RPM's and shift past 4th into 5th. I will be changing the oil, had previously bought and now will change the clutch and clutch cable. Am I heading in the right direction or should I just ride it until it dies and replace the engine? There is a sick part of me that has thought of having to split the engine and do some transmission work because everything else is perfect on this engine, but I'm not quite mental enough to take that on yet!

Thanks for all you great minds out there!

Michael