Final drive unit oil leak?
I noticed an oily residue building up on the left side of the rear
wheel, right where it joins the final drive unit (FDU). I have 3806
miles on the bike ('01 model), & my Clymer book recommends greasing the
drive shaft every 4k, so I decided to pull the FDU. Thankfully, I did
find it already greased (whew!). Now here's the weird part. There was
no gear oil or residue on the side of the FDU that connects to the
wheel. There was no oil or residue on the part of the wheel that
connects to the FDU. The gear oil level inside the FDU was normal. The
only place I found gear oil where I didn't expect it was on the spacer
shaft that fits inside the final drive ring gear (that meshes with the
wheel gear.) This is a spacer that the axle goes thru. Now, in order
for that oil to get to the outside of the FDU/wheel joint, it would
have to flow from the inside of the ring gear, which is male, to the
outside of the wheel gear, which is female, thru the grease on both
gears, then get flung to the outside of the FDU/wheel joint & seep out.
Naaaahhh, no way. So, any ideas on where the oily buildup (mixture of
brake pad dust & something else) on the wheel came from??