got into the hub/speedo gearbox - have a couple questions. I found this thing somewhere around the lock ring. looks to be part of something, dumb old me, pulled it out before engaging my brain. not sure if it's part of the speedo gearbox or what - ???
second, are the speedo gearboxes serviceable. mine has the inner ring that engages the lock ring. the inner ring has this grinding sound, and seems to be binding up internally. the parts list diagram does not show individual components, so i'm assuming it may be a "lowest replaceable unit" part, and non-serviceable - unless I'm missing something, I don't see any easy means of disassembly.
as for the top hat spacer, it seems that part of it's function is to keep the speedo gearbox from distorting when torqueing the axle shaft. the sppedo gearbox looks like it's a zinc-aluminum alloy. torqueing the axle shaft against the spacer against the speedo gearbox housing, i'm thinking, may distort the housing. just speculating....