A customer dropped off a Racing Zero for service.


It was apparently overhauled at another shop,
but the freewheel body rotation on the rear wheel was abnormally heavy,
so they haven't been using it much.

Both front and rear wheels were perfectly centered with virtually no lateral runout.
At least that part was done properly.


The freewheel body rotation was indeed abnormally heavy.
After disassembling it, I found the cause:
the lip seal on the bearing wasn't seated properly in the cone groove.
You're supposed to snap the lip seal into place before threading the hub shaft through,
but it looks like they tried to install it after the shaft was already in place, and botched it.
(Though, for the record, it is possible to install the lip seal after threading the shaft through.)

There's also a clear, oily substance on both the lip seal and shaft,
which looks like Mavic freewheel body oil.
If that's what it is, it serves no purpose here.
This oil has extremely low viscosity, which works fine in Mavic's semi-engaged design where the freewheel body
constantly rubs against the rubber seal deep in the hub body in an enclosed state—no leakage occurs.
But with Fulcrum, the waterproof seal on the back of the freewheel body is non-contact
with a gap, so Mavic oil just leaks right out.


The lip seal on the anti-freewheel side was also peeled back.

I checked the front wheel first, but I was getting uneasy about it,
so I disassembled the front hub too—but that one was fine.