RE: YS 110FZ Problems... re-build?
I don't know of any shop manual for it. Basically make sure all the case bolts are as tight as I can get them with an allen wrench, and snug on everything else. That should pretty much cover your rebuild and give you any parts you may need in the future. You might want to order bearings as well, just to have them handy as you will need them eventually.
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