↑This is a Sapim CX Sprint (straight, not bent neck, black not silver) from our shop's stock
at 310mm length, but


The CX Sprint handled by the domestic distributor has
an exceptionally long plain section at the rim end,
and comes in two types: 310mm (cuttable down to 270mm)
and 270mm (cuttable down to 240mm).
These two lengths, combined with our spoke cutter,
allow us to cover 310～240mm.


I measured the length of the 310mm spoke.



Naturally, it's 310mm.
It looks like about 309.5mm, but don't worry about that.
CX-RAY spokes are often 0.2～0.5mm shorter than their nominal length,
and while being short is fine, the variation means
that when temporarily building with spokes aligned
where the thread end just hides inside the nipple,
the initial runout on the temporary wheel is quite large.
By contrast, wheels temporarily built with spokes cut by our spoke cutter
show noticeably smaller initial runout.

The definition of "spoke length" differs between manufacturers—
broadly speaking there are two types—but DT and Sapim are the same,
and that matches my definition as well.
When I measure a spoke that Sapim calls 310mm,
I also get 310mm.


Anyway, at about 255mm down from the neck, the end of the flattened butted section appears.
There's individual variation here; most are around 256mm.

Since this spoke is cuttable down to 270mm,
when cut to 270mm, if the butted end is at 256mm,
the remaining plain section would be 14mm,
but Sapim spoke threads are about 9mm long.
The thread section formed by our spoke cutter
isn't precisely the same as Sapim's, but we can say it's about 9mm.


To make the difference clear by color,
I've lined up a silver CX-RAY generic spoke
with its thread end at 270mm.
The black CX Sprint in the previous image is from a butted-end 256mm specimen—
a different spoke from the one in the image before that.

If we cut to 270mm,
with 9mm of the remaining 14mm used for threads,
the plain section without threads after the butted end
leaves 5mm.
As you can see in the image above,
when a 310mm CX Sprint is cut to 270mm,
the plain section margin is shorter than Sapim's standard length.

If 270mm CX Sprint is needed,
cutting the 270 (～240) mm stock without cutting and just forming threads
produces a 270mm with large specific gravity and a long plain section.
By contrast, cutting a 310 (～270) mm down to 270mm
produces a 270mm with the maximum length of butted section.
I would preferably cut from 310mm,
even down to about 268mm if needed.
When the plain section becomes too short,
the butted portion threatens to enter the nipple,
but with 12mm-long nipples, you can just barely build the wheel.

... That's the story with the CX Sprint we stock.


↑This is a different batch from what we originally had—
after long stock-outs following inventory depletion due to hoarding (※),
this is the newly arrived CX Sprint
310mm black straight.

※The reason for the depletion being hoarding is
　something I cannot definitively determine

The text on the vinyl bag wasn't written by me—
it's the distributor's management in batches of 20, showing
3 bags = 60 spokes in the image.
I'll call what we originally had the "old batch"
and what came after as resupply the "new batch."


This 310mm that supposedly "can be cut down to 270mm,"


has the butted end at around 265mm.


I lined them up with the silver CX-RAY end at 270mm.
Yes, it's absolutely impossible to use at 270mm.
280mm would be the limit, or maybe 278mm if you're desperate.
In other words, the current black CX Sprint straight
is a blank spot where 280～270mm cannot be obtained.
So at our shop, we only cut from the old batch 310mm
when 280mm or less down to 270mm is needed.
The distributor has been notified of this situation.

I don't know why this happened,
but since 310mm to 270mm is minus 40mm
and 270mm to 240mm is minus 30mm,
maybe the production setup for the 270 (～240) mm spoke
accidentally got loaded into the 310mm instead.

As for whether other colors and specs of CX Sprint have the same issue,
we stock them abundantly, so we haven't had time
to investigate—nor have we bothered to.
The distributor will probably look into it eventually.
Update: Since the distributor doesn't seem to be investigating,
we looked into it ourselves (→here)

There will probably be fellow professionals out there who think
"I stock 310mm hoping to get 275mm, but I'm unsure whether that length will actually be available,"
but that's not my problem and it's none of my concern.
With a rim-brake front wheel on a 30mm high rim with radial lacing,
unless it's a hub with a particularly large flange,
you generally end up needing about that length anyway.


↑The three spokes on the left are old batch, those on the right are new batch.


↑The two spokes at the top are both old batch,
representing about the extremes of individual variation in butted-end length.
The one at the bottom is new batch with a notably short butted section,
but it still doesn't even come close to matching the old batch dimensions.