Its on the rear (non-driveside)- a sort of black plastic collar. It looks like it might clip in/around the rear hub body however its indentations are nowhere near big enough so it just hangs. Any ideas?
(That dirt is from the one very sunny/nice day that we had yesterday) 😯
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I had a snapped axle on an older ultegra wheel - took me ages to realise that's what it was and I'd been trying for days to rebuild the wheel into true
eventually I caught on when I saw that the cap wouldn't stay put
I've got the same wheels. Looks like it needs a good clean, inside and out. Then grease it all up and then what looks like a labyrinth seal on the inside of the rubber cup should cleanly engage with the hub body?
it should just be a press fit over the axle nuts and be held in place mostly by it's grip on them rather than the tabs that go into the hub body.
It's just a cover over the digital adjustment device that's on most shimano 11 speed wheels, it should just clip on.
The hub is still sealed without it, it just neatens everything up and adds a bit more protection
I've got Ultegras 6800 and rs81 c35 and they're both like this