A customer brought in the rear wheel from a Racing Zero for repairs.
A spoke suddenly broke while riding.
Since the customer isn't the original owner of this wheel,
the detailed history is unclear, but they did mention having crashed on their own,
so it's not completely out of the question.
↑This culprit
Fixed.
↑Replaced spoke
The broken pieces fit together perfectly.
There must have been a crack before the final break, and then it gave way all at once.
The darkish part of the fracture surface is the crack that had been seeping through,
and the whitish part is where it fractured suddenly at the end.
Next, the front wheel.
This one was a real headache.
Multiple nipples were stripped, and when the wheel spins,
you can see radial runout even without putting it on the truing stand.
Since apparently an amateur acquaintance of the customer worked on it,
I won't be harsh, but it's pretty messed up.
There's radial runout, but the brake surface wear marks
were consistent with the rim's profile.
In other words, they haven't used this wheel since the runout appeared.
Indeed, once it became unusable,
they've only been using the rear wheel, which explains why
the hubs show different wear patterns between front and rear.
Six nipples needed replacing,
and the image above shows the point when I marked the spokes with tape.
There was one spoke that was bent.
Both neighbors of this spoke had severely stripped nipples too,
which suggests that this spot was where someone
tried to correct the runout, causing the initial problem.
Even with this degree of deformation, if you only correct the lateral runout,
you'll see radial runout on the truing stand.
To fix both, spoke replacement is essential.
↑From this state
Fixed.
Both wheels ended up perfectly centered,
which the customer saw and verified themselves.
↑Replaced spokes
↑Replaced nipples
Were these things seriously stripped (※)?
※They were.
A spoke suddenly broke while riding.
Since the customer isn't the original owner of this wheel,
the detailed history is unclear, but they did mention having crashed on their own,
so it's not completely out of the question.
↑This culprit
Fixed.
↑Replaced spoke
The broken pieces fit together perfectly.
There must have been a crack before the final break, and then it gave way all at once.
The darkish part of the fracture surface is the crack that had been seeping through,
and the whitish part is where it fractured suddenly at the end.
Next, the front wheel.
This one was a real headache.
Multiple nipples were stripped, and when the wheel spins,
you can see radial runout even without putting it on the truing stand.
Since apparently an amateur acquaintance of the customer worked on it,
I won't be harsh, but it's pretty messed up.
There's radial runout, but the brake surface wear marks
were consistent with the rim's profile.
In other words, they haven't used this wheel since the runout appeared.
Indeed, once it became unusable,
they've only been using the rear wheel, which explains why
the hubs show different wear patterns between front and rear.
Six nipples needed replacing,
and the image above shows the point when I marked the spokes with tape.
There was one spoke that was bent.
Both neighbors of this spoke had severely stripped nipples too,
which suggests that this spot was where someone
tried to correct the runout, causing the initial problem.
Even with this degree of deformation, if you only correct the lateral runout,
you'll see radial runout on the truing stand.
To fix both, spoke replacement is essential.
↑From this state
Fixed.
Both wheels ended up perfectly centered,
which the customer saw and verified themselves.
↑Replaced spokes
↑Replaced nipples
Were these things seriously stripped (※)?
※They were.