Our spoke supplier Sapim (a Belgian spoke manufacturer) has started
carrying CX-RAY Pro, a derivative model of the CX-RAY,
so
I've already stocked some right away.
Where the CX-RAY's butted section has
a thickness of 0.9mm and width of 2.2mm,
the CX-RAY Pro has
a thickness of 1.05mm and width of 2.1mm,
resulting in a slightly more compact cross-section shape.
According to Sapim, it reduces air resistance by 30%
(though it's unclear what that 30% reduction is relative to,
even looking at the original text on the home site)
and is lighter than the CX-RAY.
Sapim lists the nominal spoke weight for
64 spokes at 260mm as
269g, so
(meanwhile the CX-RAY is 272g)
calculating the spoke specific gravity:
269÷64÷260÷0.0257＝
0.629021..., which
comes to 62.9%.
I've stocked the silver 300mm size.
Currently, CX-RAY Pro availability is
limited to silver and black J-bend spokes only,
with the longest length being 300mm
(CX-RAY comes in J-bend 306mm, straight 300mm,
and straight 310mm with a 40mm cut option for repairs).
At the longest length, the proportion of the butted section
relative to the overall spoke length is maximized,
and with silver spokes, there's no additional weight
from the slight paint coating found on black spokes,
so the CX-RAY Pro's silver 300mm should
show the smallest spoke specific gravity.
Plus, with the silver 300mm,
there's a wheel in my near-term plans that I can use it for,
so it works out conveniently
20 spokes at 300mm weighed 93.0g.
93.0÷20÷300÷0.0257＝
0.603112..., so remarkably 60.3%—
as I continue measuring,
I expect the average to come in around 61–62%.
As for CX-RAY Pro, based on the model name alone,
it gives the impression that
"the old CX-RAY was for beginners,"
making it seem like an upgraded or successor model,
but whether it will completely replace the CX-RAY remains unclear.
Since most pre-built wheels have already switched
from CX-RAY to CX-RAY Pro in their specifications,
I have a feeling they won't be very widespread, to the point
where "this wheel is still built with
CX-RAY, how outdated" becomes the prevailing sentiment.
If that happens,
most will likely use straight spokes, so unless
the supplier also starts carrying straight spokes,
replacement spoke availability will be limited to
wheel manufacturers and brands,
making them inconvenient to source and
more expensive.
Sapim has already released spokes that
Japanese suppliers aren't carrying yet, including
the RC-1, a flexible spoke made of PBO
(trademarked as Zylon by Toyo Spinning),
and the CX Carbon, an aero-profile carbon spoke.
The RC-1 requires a
3.8mm flange hole diameter on the hub side
for straight spokes,
with a nominal weight of 122g for 64 spokes at 260mm.
Calculating the spoke specific gravity from that gives roughly 28.5%.
The CX Carbon requires a
3.65mm flange hole diameter on the hub side
for straight spokes,
with a nominal weight of 185g for 64 spokes at 260mm,
which calculates to roughly 43.3% specific gravity.
I've long thought that Kashirium's Duralumin spokes
should have an asymmetrical teardrop cross-section.
The upper half of the wheel moves faster
than the bike's speed, so why not
arrange the spokes with the rounded side cutting through the wind,
mirroring left and right as they hook onto the hub flanges?
That way you wouldn't need
two different spoke types for left and right.
Sapim's CX Carbon actually features
precisely that kind of shape,
with one side of the flattened spoke section rounded
and the other side tapered.
carrying CX-RAY Pro, a derivative model of the CX-RAY,
so
I've already stocked some right away.
Where the CX-RAY's butted section has
a thickness of 0.9mm and width of 2.2mm,
the CX-RAY Pro has
a thickness of 1.05mm and width of 2.1mm,
resulting in a slightly more compact cross-section shape.
According to Sapim, it reduces air resistance by 30%
(though it's unclear what that 30% reduction is relative to,
even looking at the original text on the home site)
and is lighter than the CX-RAY.
Sapim lists the nominal spoke weight for
64 spokes at 260mm as
269g, so
(meanwhile the CX-RAY is 272g)
calculating the spoke specific gravity:
269÷64÷260÷0.0257＝
0.629021..., which
comes to 62.9%.
I've stocked the silver 300mm size.
Currently, CX-RAY Pro availability is
limited to silver and black J-bend spokes only,
with the longest length being 300mm
(CX-RAY comes in J-bend 306mm, straight 300mm,
and straight 310mm with a 40mm cut option for repairs).
At the longest length, the proportion of the butted section
relative to the overall spoke length is maximized,
and with silver spokes, there's no additional weight
from the slight paint coating found on black spokes,
so the CX-RAY Pro's silver 300mm should
show the smallest spoke specific gravity.
there's a wheel in my near-term plans that I can use it for,
so it works out conveniently
20 spokes at 300mm weighed 93.0g.
93.0÷20÷300÷0.0257＝
0.603112..., so remarkably 60.3%—
as I continue measuring,
I expect the average to come in around 61–62%.
As for CX-RAY Pro, based on the model name alone,
it gives the impression that
"the old CX-RAY was for beginners,"
making it seem like an upgraded or successor model,
but whether it will completely replace the CX-RAY remains unclear.
Since most pre-built wheels have already switched
from CX-RAY to CX-RAY Pro in their specifications,
I have a feeling they won't be very widespread, to the point
where "this wheel is still built with
CX-RAY, how outdated" becomes the prevailing sentiment.
If that happens,
most will likely use straight spokes, so unless
the supplier also starts carrying straight spokes,
replacement spoke availability will be limited to
wheel manufacturers and brands,
making them inconvenient to source and
more expensive.
Sapim has already released spokes that
Japanese suppliers aren't carrying yet, including
the RC-1, a flexible spoke made of PBO
(trademarked as Zylon by Toyo Spinning),
and the CX Carbon, an aero-profile carbon spoke.
The RC-1 requires a
3.8mm flange hole diameter on the hub side
for straight spokes,
with a nominal weight of 122g for 64 spokes at 260mm.
Calculating the spoke specific gravity from that gives roughly 28.5%.
The CX Carbon requires a
3.65mm flange hole diameter on the hub side
for straight spokes,
with a nominal weight of 185g for 64 spokes at 260mm,
which calculates to roughly 43.3% specific gravity.
I've long thought that Kashirium's Duralumin spokes
should have an asymmetrical teardrop cross-section.
The upper half of the wheel moves faster
than the bike's speed, so why not
arrange the spokes with the rounded side cutting through the wind,
mirroring left and right as they hook onto the hub flanges?
That way you wouldn't need
two different spoke types for left and right.
Sapim's CX Carbon actually features
precisely that kind of shape,
with one side of the flattened spoke section rounded
and the other side tapered.