A customer dropped off a Fulcrum rear wheel for repair.
Originally, the Fulcrum was
the flagship model of G3 lacing with steel spokes and a medium-height rim,
but at this point there's the Shamal Ultra above it, so it's second tier.
It's been converted to aluminum spokes, but since it's positioned the same as the original Racing 1 spec,
the nipples are brass rather than the current model.
A spoke has broken partway through.
The customer said it snapped with a crack sound at the moment of launching from a standstill,
but I suspect there was a crack from hitting the rear derailleur or something,
and then a final impact force caused it to break.
When retrieving the broken spoke, its nipple was incredibly stripped out,
and it was difficult to turn.
Of course, I replaced it.
I asked the customer if they remembered hitting the spoke with the rear derailleur,
or if there was a history ofsloppy wheel truing,
but since they're not the original owner of this wheel, they didn't know.
↑That's the cross-section.
The part where the crack had progressed right before breaking has a dull color,
while the part that broke from the final impact is white,
but it's hard to see, so I'll photograph just the spoke later.
Fixed.
The valve bush was missing, so I replaced it.
The valve bushes on Bora and similar wheels come in an old-style two-prong type and a new pipe type,
but the valve bush on the 2WAY-FIT aluminum rim is a four-prong type
and is a different part from the Bora valve bushes.
The current model also uses the four-prong style.
The replacement spoke
The fracture surfaces fit together perfectly.
↑The black area is the crack that had progressed right before breaking,
and the white area is the section that was still intact right before the break.
Originally, the Fulcrum was
the flagship model of G3 lacing with steel spokes and a medium-height rim,
but at this point there's the Shamal Ultra above it, so it's second tier.
It's been converted to aluminum spokes, but since it's positioned the same as the original Racing 1 spec,
the nipples are brass rather than the current model.
A spoke has broken partway through.
The customer said it snapped with a crack sound at the moment of launching from a standstill,
but I suspect there was a crack from hitting the rear derailleur or something,
and then a final impact force caused it to break.
When retrieving the broken spoke, its nipple was incredibly stripped out,
and it was difficult to turn.
Of course, I replaced it.
I asked the customer if they remembered hitting the spoke with the rear derailleur,
or if there was a history of
but since they're not the original owner of this wheel, they didn't know.
↑That's the cross-section.
The part where the crack had progressed right before breaking has a dull color,
while the part that broke from the final impact is white,
but it's hard to see, so I'll photograph just the spoke later.
Fixed.
The valve bush was missing, so I replaced it.
The valve bushes on Bora and similar wheels come in an old-style two-prong type and a new pipe type,
but the valve bush on the 2WAY-FIT aluminum rim is a four-prong type
and is a different part from the Bora valve bushes.
The current model also uses the four-prong style.
The replacement spoke
The fracture surfaces fit together perfectly.
↑The black area is the crack that had progressed right before breaking,
and the white area is the section that was still intact right before the break.