Another day working on wheels (and so on).
I received a rear wheel from a customer—it's a Cosmic Pro Carbon.
This is the rear wheel, but along with it
the front wheel spokes are heavily rusted,
so the customer wants both wheels rebuilt.
This wheel calls itself "Cosmic" but actually uses
Isopulse lacing, which was originally adopted only
on the Ksyrium lineup.
Isopulse isn't just about radial lacing on the freewheel side—
it also includes making the spoke path on the non-freewheel side
as tangential as possible. Depending on rim depth and flange diameter,
this effect is maximized at 20 holes.
This rear wheel is a rim brake model with quick-release hub, but
the Instant Drive 360 hub was chosen somewhat arbitrarily
because 12mm thru-axles won't fit through the FTS-L freewheel body
(though it does make economic sense).
The disc version of this hub just has a centerlock rotor mount attached
and the dropouts converted to thru-axle type.
For disc brake rear wheels, 20 holes is considered risky,
so they use 24 holes instead. The rim brake rear hub
is otherwise identical in design to the disc hub—
the only differences are the disc rotor mount and the dropout specifications.
The original Ksyrium SSC came out in 1999, but
it wasn't "let's just aluminum-spoke an existing wheel!"
Instead, they didn't simply aluminum-spoke an existing
steel-spoked Isopulse rear wheel.
Rather, they debuted Isopulse and aluminum spokes simultaneously,
so aluminum spokes were the "means" considered necessary at the time
to achieve the "goal" of Isopulse.
Later, the Ksyrium Elite came out—
a 20-hole steel-spoked Isopulse rear wheel—
but the non-freewheel side wasn't nearly as slack as this.
What I'm getting at is that rim brake rear wheels should use Isopulse at 20 holes,
but the hub design is "just made as an afterthought to the disc brake version."
Twenty-hole wheels are few in number, but Mavic isn't as foolish as Shimano,
so they don't make 20-hole rear wheels with spokes as thin as CX-RAY.
Instead, they use wide aero spokes with greater spoke cross-sectional area.
The spokes are hooked on both sides, so
when I release some spoke tension,
I can remove the hub.
Since the aero spoke width is smaller than the rim hole diameter on the inside,
I can pull the spokes with nipples straight out from the outside,
which makes the job easier.
The two punch-mark-like holes on either side of the rim hole
next to the valve hole indicate that this is a rear rim.
↑This is a Ksyrium Pro I have in for another job, and since it's a front rim,
there's only one dot.
I collected all the washers seated under the neck of the external nipples.
I have a habit of grouping them in fours to easily see if all 24 are there,
but even with a 2:1 lacing of 7 pairs (21 holes), I end up sorting them as
4×5 + 1 rather than 3×7.
Out of just 24 pieces, 4 had stamping defects,
so I won't reuse the original nipples and washers.
↑Going back in time, this is what the original nipples looked like.
The rim holes are designed for standard nipples,
so I'll use 12mm aluminum nipples.
I actually built it with black nipples,
but the image above shows silver aluminum nipples threaded in
to check the protrusion length.
I rebuilt the wheel reusing just the rim.
24-hole, all-black CX Sprint 44 JIS lacing,
with the hub having a fixed gear sprocket mount on one side
and a freewheel sprocket mount on the other side
—it's a Novatech fixed gear hub.
I received a rear wheel from a customer—it's a Cosmic Pro Carbon.
This is the rear wheel, but along with it
the front wheel spokes are heavily rusted,
so the customer wants both wheels rebuilt.
This wheel calls itself "Cosmic" but actually uses
Isopulse lacing, which was originally adopted only
on the Ksyrium lineup.
Isopulse isn't just about radial lacing on the freewheel side—
it also includes making the spoke path on the non-freewheel side
as tangential as possible. Depending on rim depth and flange diameter,
this effect is maximized at 20 holes.
This rear wheel is a rim brake model with quick-release hub, but
the Instant Drive 360 hub was chosen somewhat arbitrarily
because 12mm thru-axles won't fit through the FTS-L freewheel body
(though it does make economic sense).
The disc version of this hub just has a centerlock rotor mount attached
and the dropouts converted to thru-axle type.
For disc brake rear wheels, 20 holes is considered risky,
so they use 24 holes instead. The rim brake rear hub
is otherwise identical in design to the disc hub—
the only differences are the disc rotor mount and the dropout specifications.
The original Ksyrium SSC came out in 1999, but
it wasn't "let's just aluminum-spoke an existing wheel!"
Instead, they didn't simply aluminum-spoke an existing
steel-spoked Isopulse rear wheel.
Rather, they debuted Isopulse and aluminum spokes simultaneously,
so aluminum spokes were the "means" considered necessary at the time
to achieve the "goal" of Isopulse.
Later, the Ksyrium Elite came out—
a 20-hole steel-spoked Isopulse rear wheel—
but the non-freewheel side wasn't nearly as slack as this.
What I'm getting at is that rim brake rear wheels should use Isopulse at 20 holes,
but the hub design is "just made as an afterthought to the disc brake version."
Twenty-hole wheels are few in number, but Mavic isn't as foolish as Shimano,
so they don't make 20-hole rear wheels with spokes as thin as CX-RAY.
Instead, they use wide aero spokes with greater spoke cross-sectional area.
The spokes are hooked on both sides, so
when I release some spoke tension,
I can remove the hub.
Since the aero spoke width is smaller than the rim hole diameter on the inside,
I can pull the spokes with nipples straight out from the outside,
which makes the job easier.
The two punch-mark-like holes on either side of the rim hole
next to the valve hole indicate that this is a rear rim.
↑This is a Ksyrium Pro I have in for another job, and since it's a front rim,
there's only one dot.
I collected all the washers seated under the neck of the external nipples.
I have a habit of grouping them in fours to easily see if all 24 are there,
but even with a 2:1 lacing of 7 pairs (21 holes), I end up sorting them as
4×5 + 1 rather than 3×7.
Out of just 24 pieces, 4 had stamping defects,
so I won't reuse the original nipples and washers.
↑Going back in time, this is what the original nipples looked like.
The rim holes are designed for standard nipples,
so I'll use 12mm aluminum nipples.
I actually built it with black nipples,
but the image above shows silver aluminum nipples threaded in
to check the protrusion length.
I rebuilt the wheel reusing just the rim.
24-hole, all-black CX Sprint 44 JIS lacing,
with the hub having a fixed gear sprocket mount on one side
and a freewheel sprocket mount on the other side
—it's a Novatech fixed gear hub.