A customer brought in a
disc wheel from Vision, an FSA (Full Speed Ahead) TT/triathlon parts brand.
I've taken it in for service.
The industry situation these days has gotten confusing, but
this is a "disc-shaped wheel"
and not a "wheel designed for disc brakes."
Of course, nowadays there are also
"disc wheels for disc brakes" from various manufacturers.
This disc wheel is for tubular tires, but
nowadays tubular tire valves are
just slightly long enough that with a 25mm-high rim,
a valve extender isn't necessary.
So when there's an air valve hole in the outer perimeter
right at the brake zone,
it often actually makes pumping air in more difficult.
I thought maybe the hole was positioned toward the inner circumference
with this situation in mind,
but the reason turned out to be completely different.
The black square visible inside the hole
is tape the customer applied
to prevent the pump head lever (particularly the cam lever on a floor pump)
from scraping and damaging the rim.
This wheel has an interesting construction:
a standard spoked wheel was first built,
then a disc fairing was glued onto the rim.
This disc fairing cannot be removed.
As far as UCI regulations go,
if it were removable, it would be a violation.
Otherwise, things like "aftermarket aero wheel kits"
or "aftermarket disc wheel kits" would flood the market.
Examples of aero wheels with
non-removable carbon fairings glued to low-profile aluminum rims
include Mavic's original Cosmic Carbon through
the truing-capable carbon spoke Cosmic SLR series,
and wheels from HED.
↑Spokes visible through the side hole
↑Vision logo hub visible through the side hole
↑Rim hole on outer side with no truing issues
The reason the customer brought this wheel in
is that the rim is clearly shifted to the left,
and they wanted to know if it could be corrected.
The Hozan centering gauge touches the disc fairing,
so I'm using a Park Tool centering gauge instead.
Just as the customer said, the rim is indeed shifted to the left.
The rim is a wide rim, and the brake cable is anchored
with minimal spacing between the brake shoe and rim,
so the customer says that when they actually swap it
with another rear wheel (perfectly centeredor shifted right),
they need to readjust the brakes.
↑This is the second appearance of this image in the article.
When I touched the inner spokes through the side hole,
from the phase of the valve hole at the side hole,
the spokes at the adjacent rim hole going clockwise
come out from the far hub flange from my perspective,
and going counterclockwise
they come out from the near hub flange.
Therefore, I determined that the inner spoked wheel
is a standard rim.
If the valve hole is ◯, then viewing from the non-freewheel side
in the image above, the spoke positioning is
left◯right
But then something crazy came to light.
This inner wheel uses 2:1 lacing!
In other words, instead of my assumption of
right-left-rightleft◯rightleft-right-left...
it's actually
left-right-rightleft◯rightright-left-right-right...
an XI (11x) pattern.
Counting the holes revealed 21H,
so right-right-left repeats 7 times.
If this had been 24H instead,
I might have taken much longer to realize it wasn't
left-right-left-right×6 but rather right-right-left×8.
The nipples have a 6mm hex internal design with grip flats,
but nylon lock rings are embedded in the outer section.
The spokes are aero straight spokes, and when you turn the nipples,
the spoke twist synchronizes completely
(confirmed in the spoke range visible through the side hole),
so truing and centering adjustment
became impossible.
Technically, I could only adjust the two holes adjacent to the side hole.
Centering requires turning all the nipples on one side,
and to correct a left-shifted rim by tightening,
I would need to adjust all 14 nipples on the right side (the high-spoke side),
but that was totally impossible.
Also, straight spokes are a bad condition too—
if these had been butted spokes,
there would be a limit to how much the spoke could twist,
so adjustment with a "one full turn then half turn back" technique might have
worked somehow... or maybe not, since the nylon lock ring is so strong.
Let's say hypothetically the nipples could rotate without issue.
If a spoke broke at the elbow,
I'd expect serious runout,
but the non-freewheel spokes have a design
where they can be replaced from the outside with the hub axle removed.
The freewheel side... passing the spoke through the hub flange is difficult,
and I'd feel like I'm assembling a ship in a bottle.
Since I couldn't fix this one,
the customer didn't pay me any labor charges,
but I felt the value as article material was high,
so with the customer's permission,
I'm writing this up as public information about
"this is what this kind of wheel is like."
disc wheel from Vision, an FSA (Full Speed Ahead) TT/triathlon parts brand.
I've taken it in for service.
The industry situation these days has gotten confusing, but
this is a "disc-shaped wheel"
and not a "wheel designed for disc brakes."
Of course, nowadays there are also
"disc wheels for disc brakes" from various manufacturers.
This disc wheel is for tubular tires, but
nowadays tubular tire valves are
just slightly long enough that with a 25mm-high rim,
a valve extender isn't necessary.
So when there's an air valve hole in the outer perimeter
right at the brake zone,
it often actually makes pumping air in more difficult.
I thought maybe the hole was positioned toward the inner circumference
with this situation in mind,
but the reason turned out to be completely different.
The black square visible inside the hole
is tape the customer applied
to prevent the pump head lever (particularly the cam lever on a floor pump)
from scraping and damaging the rim.
This wheel has an interesting construction:
a standard spoked wheel was first built,
then a disc fairing was glued onto the rim.
This disc fairing cannot be removed.
As far as UCI regulations go,
if it were removable, it would be a violation.
Otherwise, things like "aftermarket aero wheel kits"
or "aftermarket disc wheel kits" would flood the market.
Examples of aero wheels with
non-removable carbon fairings glued to low-profile aluminum rims
include Mavic's original Cosmic Carbon through
the truing-capable carbon spoke Cosmic SLR series,
and wheels from HED.
↑Spokes visible through the side hole
↑Vision logo hub visible through the side hole
↑Rim hole on outer side with no truing issues
The reason the customer brought this wheel in
is that the rim is clearly shifted to the left,
and they wanted to know if it could be corrected.
The Hozan centering gauge touches the disc fairing,
so I'm using a Park Tool centering gauge instead.
Just as the customer said, the rim is indeed shifted to the left.
The rim is a wide rim, and the brake cable is anchored
with minimal spacing between the brake shoe and rim,
so the customer says that when they actually swap it
with another rear wheel (perfectly centered
they need to readjust the brakes.
↑This is the second appearance of this image in the article.
When I touched the inner spokes through the side hole,
from the phase of the valve hole at the side hole,
the spokes at the adjacent rim hole going clockwise
come out from the far hub flange from my perspective,
and going counterclockwise
they come out from the near hub flange.
Therefore, I determined that the inner spoked wheel
is a standard rim.
If the valve hole is ◯, then viewing from the non-freewheel side
in the image above, the spoke positioning is
left◯right
But then something crazy came to light.
This inner wheel uses 2:1 lacing!
In other words, instead of my assumption of
right-left-rightleft◯rightleft-right-left...
it's actually
left-right-rightleft◯rightright-left-right-right...
an XI (11x) pattern.
Counting the holes revealed 21H,
so right-right-left repeats 7 times.
If this had been 24H instead,
I might have taken much longer to realize it wasn't
left-right-left-right×6 but rather right-right-left×8.
The nipples have a 6mm hex internal design with grip flats,
but nylon lock rings are embedded in the outer section.
The spokes are aero straight spokes, and when you turn the nipples,
the spoke twist synchronizes completely
(confirmed in the spoke range visible through the side hole),
so truing and centering adjustment
became impossible.
Technically, I could only adjust the two holes adjacent to the side hole.
Centering requires turning all the nipples on one side,
and to correct a left-shifted rim by tightening,
I would need to adjust all 14 nipples on the right side (the high-spoke side),
but that was totally impossible.
Also, straight spokes are a bad condition too—
if these had been butted spokes,
there would be a limit to how much the spoke could twist,
so adjustment with a "one full turn then half turn back" technique might have
worked somehow... or maybe not, since the nylon lock ring is so strong.
Let's say hypothetically the nipples could rotate without issue.
If a spoke broke at the elbow,
I'd expect serious runout,
but the non-freewheel spokes have a design
where they can be replaced from the outside with the hub axle removed.
The freewheel side... passing the spoke through the hub flange is difficult,
and I'd feel like I'm assembling a ship in a bottle.
Since I couldn't fix this one,
the customer didn't pay me any labor charges,
but I felt the value as article material was high,
so with the customer's permission,
I'm writing this up as public information about
"this is what this kind of wheel is like."