Hey all again!
did some more inspecting and found the bores that the rocker shafts sit in, in the end-caps are pretty not-smooth. Though they're usually clamped down stationary except when adjusting, so I'm not sure if that matters too much? Also, is lubrication to the tach-driveshaft the only spot that matters if the cam-cap gaskets are one way or the other? It looks like like the oil passages kinda flow around the gasket in the other spots that would be direction-dependent.
I'm not as detailed on the 350 as others here but I'd consider buying some replacement cam bearing covers, there are plenty of used 350 parts around. Not sure if the diagram in the FSM showing the oil circulation might help clear up the oil flow paths, but I do know that one side will leak if the gasket is reversed (just can never remember which side).
That last one I think is for the shift lever shaft - does the scoring in there matter too much? The shaft seemed smooth otherwise.
If the shaft itself is smooth in the area where the lip of the seal sits on the shaft, it should be fine. Scoring in the aluminum inside the crankcase half would only be important if the shaft was a sloppy fit due to the wear and material missing. And the opening where the seal sits in the outside of the lower case shouldn't be damaged or misshapen in any way or it could leak around the perimeter of the seal body.
is there similar merit in disassembling the transmission shafts, and thoroughly cleaning out their bearings, and any crud that may be between the gears/shaft?
I would spend a little time checking the bearings, roll them long enough to be sure that none of the balls or needle bearings have any tight spots. If the gears all spin freely on the shafts, they generally only need a rinse.
now I'm worried that I won't be meshing the gears back up between the two shafts exactly as they were since i didn't mark corresponding teeth.
As long as all the gears, thrust washers and circlips are in place in the correct order and the gears are correctly oriented on the shafts for the engagement dogs to work correctly, it's fine. There is no specific timing or order of teeth engagement, they're just transmission gears
Should I get new circlips for those shafts instead of reusing the old ones?
I've never had to replace any, but if they're difficult to remove from the shaft and any of them get bent because of it then yes. As long as you're careful it should be fine.
And is backlash and other things measured after oiling/greasing/assembly-lubing the parts, or while they're all still dry?
Good question and one that I've never worried about. These transmissions are pretty durable, usually it's clearly evident when something is worn or damaged and needs to be replaced. When I've ridden a bike that rides and shifts fine, if it needs disassembly I give things a good visual inspection but unless I see something that is a problem I generally use my eye to check general clearances, looking for excess. If something seems off enough to investigate, then I'll be concerned about getting out the feeler gauges. I have bigger concerns for using straight shift forks and checking the shift drum for wear in the pathways for each fork's movement as well as the pins for the shift forks, and the detent mechanism on the shift drum end before clutch re-installation.
Also for what it's worth, how do the transmission gears stay sufficiently oiled? I see the oil feed to the mainshaft needle bearing, but can't seem to figure out how the rest of it stays lubed other than just splashes.
Check the oil flow diagram for that too.
Sorry, I might be over-thinking these things but wanted to see y'alls thoughts. Thank you!
Nah, better to overthink a little bit than rush to get it back together and pay for it later.
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