'83 kz1100 stuck in 3rd gear

Yes! rear wheel out to release the shaft from the engine.
Sounds like something preventing the drum from turning.
If it isn't the return spring it could be the arms that hook the pins on the selector drum.
If the small spring on those has failed they won't pull the drum round..
If you find nothing wrong there you need to drop the sump to view the rest of the transmission.

These pics might help. Do yourself a favor and check the condition of the clutch push rod while at it. If it has any wear at the hole where it sticks out of the engine, replace it with a new one.
The worse part of the process for me was removing the old gasket material from the engine. Gotta be a contortionist while being patient, careful, and thorough about getting it all off without damaging the aluminum gasket surfaces.

I'm having one hell of a time trying to get the swingarm off. Those push nipples, or whatever the devil named em, don't want to budge. I've used an oxy-acetylene torch and heated them, tapped it to use a bigger bolt as a puller, they won't budge. Any advice please?

You don't need the swing arm off.
Just unbolt the wheel to allow the shaft to slide clear of the bevel box..
See Daveos pic above..

zed1015 wrote: You don't need the swing arm off.
Just unbolt the wheel to allow the shaft to slide clear of the bevel box..
See Daveos pic above..

+1 Leave the swing arm attached to the frame, and save that project for another day!
Remove the rear differential case from the swing arm (four nuts), and set it aside vertically so the gear lube doesn't leak out.
I placed a wood support block under the engine, and removed the rear upper left motor mount to gain visual and working access clearance.



Note* The drive shaft must be rotated so the release PIN at the engine end is accessible from the top when the rubber dust boot is pulled back, visible in 1st pic posted above.
The release pin must be pressed in for the drive shaft to disengage from the front bevel gear case. Drive shaft disengagement and re-engagement will likely be a tedious procedure, requiring some diligent patience.




I hope this helps... :whistle:

Merry New Year, and to all a good ride!

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