I've received numerous comments asking me to write about aluminum spokes,
and I've also been asked about them by customers who've visited the shop.
At the very least, the claim by some clueless person (playing dumb)
that "aluminum spokes are essentially meaningless compared to steel spokes" is clearly wrong.
As evidence, I could just say "if you use Racing Zero for a bit,
it becomes obvious that it's a wheel with a stiffness that can't be achieved with steel spokes,"
and call it a day with a gut-feel argument,
but instead I'll explain how this applies to the wheel philosophy I use at my shop.
"First spoke tension (hereafter First ST)"
"Second spoke tension (hereafter Second ST)"
"Spoke specific gravity"
"Beaker theory"
These are what I'll apply to aluminum spokes, but
the beaker theory discussion (which I've never touched on before) is lengthy and
doesn't directly relate to aluminum spokes, so I'll save that for another day.
First, about First ST.
First ST refers to the numerical value shown on the spoke tension meter,
the "meter reading" itself.
Just to be clear, this is shop terminology.
Second ST is the approximate value of spoke tension when First ST is plugged into a conversion table,
and generally when people say "spoke tension," this is what they mean.
Some would reasonably argue that we don't need such confusing terminology—
First ST is just "meter reading" and Second ST is just "spoke tension"—
but First ST also increases and decreases with nipple tightening and loosening,
it's a type of spoke tension quantified,
and we can't discuss wheel stiffness or drive stiffness using only
spoke tension (i.e., Second ST).
I'll explain why below.
Aluminum spokes use the flat-oval aero design from Racing Zero
(a square aero with uniformly-shaped butted sections), which I call "ribbon-like."
This isn't a deliberately convenient choice to lead to a predetermined result—
it's because aluminum spokes are considered the least prone to observational bias
when expressing my thoughts on pure observational facts.
In that regard, tie-shaped spokes are no good.
I'll write about that later,
but first I'll explain why I don't choose Mavic aluminum spokes.
Mavic aluminum spokes come in at least four types.
There may be more, but I'm just not well-informed enough.
The "H1ST" in the diagram above—ignore that for now.
First, spoke #1 has a shape that's been around since the original Ksyrium SSC,
with ridge-like lines at the edges of the butted section resembling fish fins,
making it the type with the greatest front-to-back width.
Spoke #2 has less front-to-back width than #1 and no ridge at the butted boundary.
Spoke #3 is a round-section spoke.
Spoke #4 resembles #2 but has a different flattening ratio.
From the original Ksyrium through ES, the spline portion where the tool grips uses
a small-diameter nipple,
but R-SYS nipples have larger-diameter splines and use different tools.
Ksyrium after R-SYS onward uses R-SYS-sized nipples,
and in all cases the nipple is encapsulated during spoke manufacture,
so we can't measure spoke weight as individual pieces.
This makes it difficult to obtain accurate spoke specific gravity.
This is why I don't use Mavic spokes when discussing aluminum spokes.
↑ Spoke #1
↑ Spoke #2
↑ Spoke #3
Regarding spoke #4 (→here)
Next, about the relationship between First ST and Second ST.
This overlaps with what I wrote before (→here)(→here), but I'll touch on it lightly.
Regarding Third ST, I won't touch on the heart of the matter,
but I'll write about it when discussing beaker theory.
If it were true that "when First ST doubles, Second ST also doubles, and
when First ST becomes n times, Second ST also becomes n times...,"
then a graph of the First ST to Second ST relationship would be a straight line of proportionality.
But in reality, that's not the case. That's why a conversion table is necessary.
As written in the linked articles,
DT and Park Tool tension meters are calibrated against
conversion tables and are said to have no individual error (Park Tool is somewhat questionable).
Hozan, on the other hand, acknowledges individual meter errors and
supplies a conversion table for each meter.
For example, with my Hozan meter, when First ST shows 130 with a #14 plain spoke,
Second ST is 1000N according to the conversion table.
Second ST should be the same value if each instrument is accurate,
but First ST shows completely different numbers if the tension meter manufacturer differs,
and there are slight errors even between products of the same (supposedly identical) type.
From here on, as shown in the diagram above,
I'll call the First ST measured with a Hozan tension meter H1ST.
For DT it would be D1ST, and for Park Tool it would be P1ST.
When measuring the same spoke, the numerical values of H1ST, D1ST, and P1ST are all over the place,
but when each is plugged into its respective conversion table, the resulting Second ST is the same.
This is the conversion table for my Hozan tension meter.
As I mentioned before, for Hozan, H1ST is considered to vary
by the number of meters they've made.
This is a graph of First ST and Second ST.
The horizontal and vertical axes are opposite to what I drew, so the curve's bending is reversed, but
when I hold this one up to the light and look through it from behind, it becomes the same.
Since DT's conversion table is this way (horizontal axis: Second ST, vertical axis: First ST),
I've gotten into the habit of drawing it that way.
It's unrelated to today's discussion, but the curve shape resembles
a stress-strain curve, so it's easier to visualize various things when viewed that way.
Specific First ST numerical values look like this.
The Hozan tension meter only has markings for First ST on
#13, #14, and #15 plain spokes—
I don't know the values for butted spokes.
So I can't measure Competition or CX-RAY with this.
This is DT's graph (Champion #14 plain).
There's also a numerical table.
The first thing I did was create a comparison table between D1ST and H1ST.
To be specific, suppose a certain Competition (#14 size)
shows D1ST of 2.00.
According to DT's conversion table, when D1ST is 1.96, Second ST is 1200N,
and at 2.04 it's 1300N,
so this Competition's Second ST would be around 1250N,
but when viewed on H1ST it shows 134.
According to Hozan's conversion table, a #14 plain at 1300N Second ST shows 138,
and a #15 plain shows 126, so it roughly matches reality.
I've created such detailed conversion tables for butted spokes
and a "H1ST table for butted spokes" from my regular spoke checks,
so I can measure butted spokes with the Hozan tension meter.
For Sapim spokes, I assume they're identical to DT spokes with the same cross-sectional dimensions,
and I derive H1ST from DT's conversion table.
Plain spoke Leader and Champion are basically the same,
but I also treat CX-RAY and Aerolite, Race and Competition as equivalent.
Actually, Race has a clearly longer 1.8mm round butted section than Competition,
to the point where it affects the decimal places in spoke specific gravity,
but I judge there's no problem in wheel building even if we treat Race's D1ST or H1ST the same as Competition's.
For Laser and Revolution, I don't use them regularly, so
when building wheels with these spokes, I use the DT tension meter.
Finding H1ST is extremely tedious, so besides that use,
I don't use the DT meter except to check H1ST.
One important thing.
The D1ST in DT's conversion table is the numerical value measured with the probe applied from the left-right direction of the spoke.
(Pseudo-Aerolite) CX-RAY measured just under 0.38.
Aerolite is 1000N at 0.37 and 1050N at 0.41, so
this CX-RAY's Second ST is just over 1000N.
When I measured from the front-to-back direction, the value jumped to 2.19.
This isn't a value used in the conversion table, but
"When Aerolite's D1ST from left-right direction is 0.38, from front-to-back it's 2.19"—
I'm actually collecting such detailed numerical values.
The reason—which I'll explain later—is that H1ST basically uses front-to-back direction measurements.
By the way, the "front-to-back" H1ST for this spoke is 130.
Unless otherwise noted, H1ST values from here on are measured in the front-to-back direction.
Also remember this for later: "When you measure a flattened spoke on the side with the larger radius
versus the side with the smaller radius, you get a larger value."
I've compiled H1ST and D1ST for #13, #14, and #15 plain spokes
when Second ST is 1000N.
Round spokes show the same First ST regardless of measurement direction.
The magnitude of First ST appears to numerically quantify
the felt stiffness of a wheel and how well it feels under pedaling.
Since it quantifies the resistance to deformation in front-to-back and left-right directions respectively,
for example, expressing 1000N of #14 plain in D1ST terms would be
left-right deformation resistance 2.19, front-to-back deformation resistance 2.19,
and Aerolite at just over 1000N would be
left-right deformation resistance 0.38, front-to-back deformation resistance 2.19—
I think it can be expressed this way.
As the simplest wheel, considering a radial-spoked front wheel,
a front wheel with #13 plain at H1ST 155 and
a front wheel with #15 plain at H1ST 116 have
the same spoke tension (Second ST),
yet there's no doubt that the front one feels stiffer and deflects less when ridden or flexed.
If it were true that "as long as Second ST is the same regardless of First ST,
wheel stiffness would be identical,"
then spokes would need only be as light as possible within a range that doesn't cause plastic deformation under tension—
To take an extreme example, suppose there was an ultra-thin plain spoke with
H1ST of around 50 but achievable Second ST of 1000N;
if we could still maintain 1000N of tension,
that would supposedly give the same stiffness as #13 at H1ST 155.
Of course, that's nonsense.
Even when spoke tension (Second ST) is the same,
different First ST means different wheel stiffness.
Of course, spokes with greater First ST relative to Second ST
have larger spoke specific gravity,
which is a drawback for weight reduction.
By the way, the ratio between H1ST and D1ST is not the same. Not even close.
This is an extremely troubling issue for me,
and I'll explain it when discussing beaker theory.
Sapim's CX and CX-RAY are both
elliptical-section flattened (elliptic aero) spokes,
with spoke specific gravities of 100% and 65% respectively.
From the manufacturer's published values, rough estimates are 98.9% and 63.6%,
but my measurements show them about 1% heavier.
Anyway, let's just go with 100% and 65%.
When these spokes are tensioned to the maximum
(the point where nipples can't be tightened further),
H1ST is around 190 for CX and around 150 for CX-RAY.
That black CX-RAY earlier at H1ST 130 is
the front wheel of my shop's wheel #5,
but I wouldn't dream of tensioning it to 150 (and couldn't anyway).
You see H1ST of 150 on CX-RAY when it's a 24-spoke front wheel
with a four-cross lacing pattern on the free side tensioned to the max
(otherwise the non-free side becomes slack),
and even then, only certain rims can handle it.
Specifically, something like Mechanico's complete wheel rear.
I've graphed the relationship between First ST and spoke specific gravity for CX and CX-RAY.
To avoid appearing biased, I've taken care to draw this
with the same numerical ratio as shown in the square to the right,
following the grid on the whiteboard.
Now imagine if we laid out elliptic aero spokes
with spoke specific gravity changed in 1% increments from CX to CX-RAY—
what kind of point grouping would that create?
CX and CX-RAY differ in their flattening ratio.
CX is slightly more compact.
Flattening ratio is 1 for round spokes, so the further from that, the flatter it is.
If I reduce spoke specific gravity to 65% while maintaining CX's flattening ratio,
I thought about the point grouping.
In reality there would be a bit more scatter, but
you can see that "it probably draws a pretty straight line through here,"
and that drawn line is the blue dashed line.
Since CX-RAY's actual flattening ratio isn't 2.15 but 2.44,
a spoke with flattening ratio 2.15 and spoke specific gravity 65% should
receive an upward correction to First ST
(because the difference between D1ST left-right and front-to-back is the basis for this).
If flattening ratio changes gradually from CX to CX-RAY,
the blue dashed line would rise into a blue solid line,
looking something like this.
Well, whether it's a bit curved or more linear
doesn't really matter for the discussion going forward.
I'm sure someone's thinking "Get to the aluminum spokes already,"
but all this setup was necessary.
And here we are.
Fulcrum's ribbon-like aluminum spokes.
H1ST was 268.
This is a somewhat exceptional value.
It's because I'm tensioning the pre-brass-nipple Racing 1 even further.
On a current aluminum-nipple Racing Zero front or rear right,
H1ST is around 235.
Below 220, the ride feel obviously becomes mushy.
Recently, I re-tensioned a Racing Zero 2WAY-FIT from a shop that did a rim swap,
because it was obviously mushy (→here).
The minimum H1ST was 205 and maximum 220 there.
I've tensioned it from there up to a minimum of 230 and average of 235.
I did communicate these numbers to the customer.
Not with the intention of "maintain H1ST of 235 on some other Hozan in the future,"
but to show "this matches the other Racing Zero models at our shop."
Next, let me measure spoke specific gravity.
But first.
There's the question of how to define spoke length for this aluminum spoke.
Is it the total length (diagram A above),
or do I measure the length below the head (B in same diagram)?
The nominal length of this spoke is 279.2mm,
and when I checked what that measurement covered,
it matched exactly total length A, so I'll use that.
From a spoke-specific-gravity perspective, it's slightly disadvantageous, but.
I'm using a scale that can measure from 0.1g so I can calculate with fewer samples.
I don't think anodize color causes weight differences, but
let me measure them separately just in case.
↑ Black, 24 pieces
↑ Silver, 5 pieces
↑ Red, 7 pieces
↑ 36 pieces total
Per spoke seems to be just over 5g.
So this spoke's specific gravity came out to 69.8%.
Since I rounded Sapim values too, let's call this 70%.
When I added this to the earlier diagram.
You can see it's way off the charts, right?
Where exactly is "basically the same as steel spokes"?
Are they going to insist that "First ST is unrelated to drive stiffness!"
even after seeing this?
and I've also been asked about them by customers who've visited the shop.
At the very least, the claim by some clueless person (playing dumb)
that "aluminum spokes are essentially meaningless compared to steel spokes" is clearly wrong.
As evidence, I could just say "if you use Racing Zero for a bit,
it becomes obvious that it's a wheel with a stiffness that can't be achieved with steel spokes,"
and call it a day with a gut-feel argument,
but instead I'll explain how this applies to the wheel philosophy I use at my shop.
"First spoke tension (hereafter First ST)"
"Second spoke tension (hereafter Second ST)"
"Spoke specific gravity"
"Beaker theory"
These are what I'll apply to aluminum spokes, but
the beaker theory discussion (which I've never touched on before) is lengthy and
doesn't directly relate to aluminum spokes, so I'll save that for another day.
First, about First ST.
First ST refers to the numerical value shown on the spoke tension meter,
the "meter reading" itself.
Just to be clear, this is shop terminology.
Second ST is the approximate value of spoke tension when First ST is plugged into a conversion table,
and generally when people say "spoke tension," this is what they mean.
Some would reasonably argue that we don't need such confusing terminology—
First ST is just "meter reading" and Second ST is just "spoke tension"—
but First ST also increases and decreases with nipple tightening and loosening,
it's a type of spoke tension quantified,
and we can't discuss wheel stiffness or drive stiffness using only
spoke tension (i.e., Second ST).
I'll explain why below.
Aluminum spokes use the flat-oval aero design from Racing Zero
(a square aero with uniformly-shaped butted sections), which I call "ribbon-like."
This isn't a deliberately convenient choice to lead to a predetermined result—
it's because aluminum spokes are considered the least prone to observational bias
when expressing my thoughts on pure observational facts.
In that regard, tie-shaped spokes are no good.
I'll write about that later,
but first I'll explain why I don't choose Mavic aluminum spokes.
Mavic aluminum spokes come in at least four types.
There may be more, but I'm just not well-informed enough.
The "H1ST" in the diagram above—ignore that for now.
First, spoke #1 has a shape that's been around since the original Ksyrium SSC,
with ridge-like lines at the edges of the butted section resembling fish fins,
making it the type with the greatest front-to-back width.
Spoke #2 has less front-to-back width than #1 and no ridge at the butted boundary.
Spoke #3 is a round-section spoke.
Spoke #4 resembles #2 but has a different flattening ratio.
From the original Ksyrium through ES, the spline portion where the tool grips uses
a small-diameter nipple,
but R-SYS nipples have larger-diameter splines and use different tools.
Ksyrium after R-SYS onward uses R-SYS-sized nipples,
and in all cases the nipple is encapsulated during spoke manufacture,
so we can't measure spoke weight as individual pieces.
This makes it difficult to obtain accurate spoke specific gravity.
This is why I don't use Mavic spokes when discussing aluminum spokes.
↑ Spoke #1
↑ Spoke #2
↑ Spoke #3
Regarding spoke #4 (→here)
Next, about the relationship between First ST and Second ST.
This overlaps with what I wrote before (→here)(→here), but I'll touch on it lightly.
Regarding Third ST, I won't touch on the heart of the matter,
but I'll write about it when discussing beaker theory.
If it were true that "when First ST doubles, Second ST also doubles, and
when First ST becomes n times, Second ST also becomes n times...,"
then a graph of the First ST to Second ST relationship would be a straight line of proportionality.
But in reality, that's not the case. That's why a conversion table is necessary.
As written in the linked articles,
DT and Park Tool tension meters are calibrated against
conversion tables and are said to have no individual error (Park Tool is somewhat questionable).
Hozan, on the other hand, acknowledges individual meter errors and
supplies a conversion table for each meter.
For example, with my Hozan meter, when First ST shows 130 with a #14 plain spoke,
Second ST is 1000N according to the conversion table.
Second ST should be the same value if each instrument is accurate,
but First ST shows completely different numbers if the tension meter manufacturer differs,
and there are slight errors even between products of the same (supposedly identical) type.
From here on, as shown in the diagram above,
I'll call the First ST measured with a Hozan tension meter H1ST.
For DT it would be D1ST, and for Park Tool it would be P1ST.
When measuring the same spoke, the numerical values of H1ST, D1ST, and P1ST are all over the place,
but when each is plugged into its respective conversion table, the resulting Second ST is the same.
This is the conversion table for my Hozan tension meter.
As I mentioned before, for Hozan, H1ST is considered to vary
by the number of meters they've made.
This is a graph of First ST and Second ST.
The horizontal and vertical axes are opposite to what I drew, so the curve's bending is reversed, but
when I hold this one up to the light and look through it from behind, it becomes the same.
Since DT's conversion table is this way (horizontal axis: Second ST, vertical axis: First ST),
I've gotten into the habit of drawing it that way.
It's unrelated to today's discussion, but the curve shape resembles
a stress-strain curve, so it's easier to visualize various things when viewed that way.
Specific First ST numerical values look like this.
The Hozan tension meter only has markings for First ST on
#13, #14, and #15 plain spokes—
I don't know the values for butted spokes.
So I can't measure Competition or CX-RAY with this.
This is DT's graph (Champion #14 plain).
There's also a numerical table.
The first thing I did was create a comparison table between D1ST and H1ST.
To be specific, suppose a certain Competition (#14 size)
shows D1ST of 2.00.
According to DT's conversion table, when D1ST is 1.96, Second ST is 1200N,
and at 2.04 it's 1300N,
so this Competition's Second ST would be around 1250N,
but when viewed on H1ST it shows 134.
According to Hozan's conversion table, a #14 plain at 1300N Second ST shows 138,
and a #15 plain shows 126, so it roughly matches reality.
I've created such detailed conversion tables for butted spokes
and a "H1ST table for butted spokes" from my regular spoke checks,
so I can measure butted spokes with the Hozan tension meter.
For Sapim spokes, I assume they're identical to DT spokes with the same cross-sectional dimensions,
and I derive H1ST from DT's conversion table.
Plain spoke Leader and Champion are basically the same,
but I also treat CX-RAY and Aerolite, Race and Competition as equivalent.
Actually, Race has a clearly longer 1.8mm round butted section than Competition,
to the point where it affects the decimal places in spoke specific gravity,
but I judge there's no problem in wheel building even if we treat Race's D1ST or H1ST the same as Competition's.
For Laser and Revolution, I don't use them regularly, so
when building wheels with these spokes, I use the DT tension meter.
Finding H1ST is extremely tedious, so besides that use,
I don't use the DT meter except to check H1ST.
One important thing.
The D1ST in DT's conversion table is the numerical value measured with the probe applied from the left-right direction of the spoke.
(Pseudo-Aerolite) CX-RAY measured just under 0.38.
Aerolite is 1000N at 0.37 and 1050N at 0.41, so
this CX-RAY's Second ST is just over 1000N.
When I measured from the front-to-back direction, the value jumped to 2.19.
This isn't a value used in the conversion table, but
"When Aerolite's D1ST from left-right direction is 0.38, from front-to-back it's 2.19"—
I'm actually collecting such detailed numerical values.
The reason—which I'll explain later—is that H1ST basically uses front-to-back direction measurements.
By the way, the "front-to-back" H1ST for this spoke is 130.
Unless otherwise noted, H1ST values from here on are measured in the front-to-back direction.
Also remember this for later: "When you measure a flattened spoke on the side with the larger radius
versus the side with the smaller radius, you get a larger value."
I've compiled H1ST and D1ST for #13, #14, and #15 plain spokes
when Second ST is 1000N.
Round spokes show the same First ST regardless of measurement direction.
The magnitude of First ST appears to numerically quantify
the felt stiffness of a wheel and how well it feels under pedaling.
Since it quantifies the resistance to deformation in front-to-back and left-right directions respectively,
for example, expressing 1000N of #14 plain in D1ST terms would be
left-right deformation resistance 2.19, front-to-back deformation resistance 2.19,
and Aerolite at just over 1000N would be
left-right deformation resistance 0.38, front-to-back deformation resistance 2.19—
I think it can be expressed this way.
As the simplest wheel, considering a radial-spoked front wheel,
a front wheel with #13 plain at H1ST 155 and
a front wheel with #15 plain at H1ST 116 have
the same spoke tension (Second ST),
yet there's no doubt that the front one feels stiffer and deflects less when ridden or flexed.
If it were true that "as long as Second ST is the same regardless of First ST,
wheel stiffness would be identical,"
then spokes would need only be as light as possible within a range that doesn't cause plastic deformation under tension—
To take an extreme example, suppose there was an ultra-thin plain spoke with
H1ST of around 50 but achievable Second ST of 1000N;
if we could still maintain 1000N of tension,
that would supposedly give the same stiffness as #13 at H1ST 155.
Of course, that's nonsense.
Even when spoke tension (Second ST) is the same,
different First ST means different wheel stiffness.
Of course, spokes with greater First ST relative to Second ST
have larger spoke specific gravity,
which is a drawback for weight reduction.
By the way, the ratio between H1ST and D1ST is not the same. Not even close.
This is an extremely troubling issue for me,
and I'll explain it when discussing beaker theory.
Sapim's CX and CX-RAY are both
elliptical-section flattened (elliptic aero) spokes,
with spoke specific gravities of 100% and 65% respectively.
From the manufacturer's published values, rough estimates are 98.9% and 63.6%,
but my measurements show them about 1% heavier.
Anyway, let's just go with 100% and 65%.
When these spokes are tensioned to the maximum
(the point where nipples can't be tightened further),
H1ST is around 190 for CX and around 150 for CX-RAY.
That black CX-RAY earlier at H1ST 130 is
the front wheel of my shop's wheel #5,
but I wouldn't dream of tensioning it to 150 (and couldn't anyway).
You see H1ST of 150 on CX-RAY when it's a 24-spoke front wheel
with a four-cross lacing pattern on the free side tensioned to the max
(otherwise the non-free side becomes slack),
and even then, only certain rims can handle it.
Specifically, something like Mechanico's complete wheel rear.
I've graphed the relationship between First ST and spoke specific gravity for CX and CX-RAY.
To avoid appearing biased, I've taken care to draw this
with the same numerical ratio as shown in the square to the right,
following the grid on the whiteboard.
Now imagine if we laid out elliptic aero spokes
with spoke specific gravity changed in 1% increments from CX to CX-RAY—
what kind of point grouping would that create?
CX and CX-RAY differ in their flattening ratio.
CX is slightly more compact.
Flattening ratio is 1 for round spokes, so the further from that, the flatter it is.
If I reduce spoke specific gravity to 65% while maintaining CX's flattening ratio,
I thought about the point grouping.
In reality there would be a bit more scatter, but
you can see that "it probably draws a pretty straight line through here,"
and that drawn line is the blue dashed line.
Since CX-RAY's actual flattening ratio isn't 2.15 but 2.44,
a spoke with flattening ratio 2.15 and spoke specific gravity 65% should
receive an upward correction to First ST
(because the difference between D1ST left-right and front-to-back is the basis for this).
If flattening ratio changes gradually from CX to CX-RAY,
the blue dashed line would rise into a blue solid line,
looking something like this.
Well, whether it's a bit curved or more linear
doesn't really matter for the discussion going forward.
I'm sure someone's thinking "Get to the aluminum spokes already,"
but all this setup was necessary.
And here we are.
Fulcrum's ribbon-like aluminum spokes.
H1ST was 268.
This is a somewhat exceptional value.
It's because I'm tensioning the pre-brass-nipple Racing 1 even further.
On a current aluminum-nipple Racing Zero front or rear right,
H1ST is around 235.
Below 220, the ride feel obviously becomes mushy.
Recently, I re-tensioned a Racing Zero 2WAY-FIT from a shop that did a rim swap,
because it was obviously mushy (→here).
The minimum H1ST was 205 and maximum 220 there.
I've tensioned it from there up to a minimum of 230 and average of 235.
I did communicate these numbers to the customer.
Not with the intention of "maintain H1ST of 235 on some other Hozan in the future,"
but to show "this matches the other Racing Zero models at our shop."
Next, let me measure spoke specific gravity.
But first.
There's the question of how to define spoke length for this aluminum spoke.
Is it the total length (diagram A above),
or do I measure the length below the head (B in same diagram)?
The nominal length of this spoke is 279.2mm,
and when I checked what that measurement covered,
it matched exactly total length A, so I'll use that.
From a spoke-specific-gravity perspective, it's slightly disadvantageous, but.
I'm using a scale that can measure from 0.1g so I can calculate with fewer samples.
I don't think anodize color causes weight differences, but
let me measure them separately just in case.
↑ Black, 24 pieces
↑ Silver, 5 pieces
↑ Red, 7 pieces
↑ 36 pieces total
Per spoke seems to be just over 5g.
So this spoke's specific gravity came out to 69.8%.
Since I rounded Sapim values too, let's call this 70%.
When I added this to the earlier diagram.
You can see it's way off the charts, right?
Where exactly is "basically the same as steel spokes"?
Are they going to insist that "First ST is unrelated to drive stiffness!"
even after seeing this?
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