I still have more unfinished nupoke stories to cover, so I'll take it bit by bit.
Today's topic is about spoke routing when doing radial lacing.
First, let me explain since it's been a while.
On this blog, we call spokes that thread from inside the hub flange to outside
"nupoke,"
and spokes that thread from outside the hub flange to inside
"anti-nupoke."
↑In tangential lacing, the spokes threaded through the flange alternate between nupoke and anti-nupoke,
but in radial lacing they consist of only one type or the other.
↑This is a Shimano WH-R501, laced radially with anti-nupoke spokes.
Nearly all complete wheelsets using butted spokes in radial lacing are built with "anti-nupoke radial" lacing,
with only very rare exceptions.
The Tni wheel I mentioned yesterday (thanks for all the inquiries) was also
built as anti-nupoke radial, keeping it understated since it's a stock wheel.
Though I said "keeping it understated," I sometimes build wheels in "nupoke radial" lacing.
This isn't a common lacing method, but compared to anti-nupoke radial,
it has both advantages and disadvantages. After weighing these,
I choose nupoke radial when it seems more beneficial.
Whether nupoke or anti-nupoke, I base lateral stiffness calculations on the root of the spoke,
in other words where the spoke emerges from the hub flange.
Anti-nupoke has a narrower base, so it has inferior lateral stiffness
compared to nupoke (in my assessment).
This is the structural stiffness characteristic of anti-nupoke radial lacing, but
let's also consider the aerodynamic side.
Though the rim-side portion of the spoke is hidden by the rim and tire,
anti-nupoke radial has a smaller frontal projection area,
making it aerodynamically advantageous.
In nupoke radial lacing, compared to anti-nupoke radial,
more of the spoke is exposed beyond the rim or tire.
Aerodynamically at a disadvantage. However, since the spoke's deflection starting point
is a wider span, it's advantageous in lateral stiffness.
Additionally, with anti-nupoke, the spoke neck opens outward as it leaves the flange.
With nupoke, by contrast, it bends inward, and
nupoke spokes are less prone to spoke breakage at the neck.
This is the biggest reason I build wheels with nupoke radial lacing.
Some complete wheelsets with butted spokes have extremely thick flanges
and use custom-length spokes fitted to match, reducing spoke breakage risk
in anti-nupoke radial lacing.
Rolf Prima is an example of this.
They use custom White Industries hubs (with custom phase angles for paired spokes)
paired with custom-dimension Sapim spokes—quite thorough.
The (likely main) reason manufacturers avoid nupoke radial lacing is the risk of spoke-to-hub-flange interference,
depending on flange shape (especially height). The kind of contact shown above
never occurs with anti-nupoke radial lacing.
The severity of this problem varies with rim height.
With low rims, nupoké spokes angle steeply toward the rim,
making flange contact less likely, but
as the rim gets taller, spoke angle flattens, causing flange contact problems.
Even when I want nupoke radial, if the rim is tall I often give up
and go with anti-nupoke radial instead.
Same rim height, but the 45mm from the Edge era and the 45mm from Envé.
I'm building these at this rim height with nupoke radial lacing.
↑My mysterious Cosmic Carbon wheel also has the non-drive-side radial laced as nupoke.
A wheel being temporarily built with nupoke radial lacing
has spokes that bulge outward.
Unrelated note, but the hub is a Suntour Superior Pro.
Before building
After building
On a different topic,
I'm often asked about the stiffness feel of Tni AL300 rim wheels.
I don't know.
So I built a front wheel for myself.
This is also nupoke radial lacing.
The hub is a White Industries H-2,
and the spokes are Sapim CX-RAY.
The top of the image is the direction of travel.
The hub lettering ends up backward, but that's intentional. I'll explain why later.
Of course it's also possible to build yesterday's Nomu Lab wheel with CX-RAY spokes,
at an upcharge of ¥5,000 per wheel (for 20H).
For 24H it's ¥6,000 upcharge.
I chose this hub for a reason:
the hub flange isn't perfectly straight.
↑Exaggerated a lot, it's something like this.
I chose it because it doesn't seem prone to flange contact problems.
Unrelated to nupoke, but...
This time I built the wheel with the image top being the direction of travel.
This makes the lettering read backward.
I think the correct orientation is having the hub adjustment grub screw hole
on the left side facing forward, but doing so makes the lettering backward.
Still, I believe this is the correct way.
On rear hubs, this grub screw hole is on the left side.
(The right has the freewheel body, so that's impossible.)
Thinking "adjustment mechanism on the left for both front and rear,"
it should be this way. There's another hub from a different manufacturer
that supports this theory.
↑This is a rear hub from a manufacturer called Extralite.
The adjustment mechanism is naturally on the left side.
A file-marked dial-like feature is attached to the left side of the hub body.
And this is a front hub, which has the same file-marked dial
on the right side (when looking from the direction text reads).
However, the hub body has "LeftSide>>" explicitly noted, so
they're saying to build it in this orientation.
The rear hub logo reads forward with travel direction, while the front hub reads backward.
I determined the White H-2 hub follows the same logic,
so I built it the way that looks backward at first glance.
My 4820g Akamatsu aluminum bike has a front wheel built with
an Akamatsu Systema hub.
While there are lighter hubs available, I chose this one because I wanted it,
prioritizing my preference over weight.
It's a truly excellent hub. Alright, I'll say it.
This is just shameless promotion of the Systema hub.
...Sorry. Please ignore that.
The flange width is narrow, so lateral stiffness is structurally limited,
but you don't notice it unless you're standing on the pedals hard.
Since the flange is already narrow, rather than trying to boost lateral stiffness
with nupoke radial, I'm aiming for ultimate minimal spoke frontal projection area
with anti-nupoke radial.
Narrow! Aerodynamically it's a pretty tasty front wheel.
With the White H-2 hub it looks like this.
Since the H-2 has quite wide flanges, these two wheels
represent the opposite extremes of radial lacing.
The reason the Systema hub has a narrow flange is
because it's also designed for use on small-wheeled bikes.
When calculated, a 700C rim with the same inner diameter as a 20-inch (HE) small-wheel rim
would be approximately 90mm in rim height.
If you build that rim with nupoke radial lacing, spoke angle becomes quite steep,
making flange contact problems more likely.
Or even with tangential lacing, half the spokes are nupoke.
With tangential lacing plus woven spoke intersections, the angle at which
nupoke emerges from the flange becomes steeper than radial lacing.
Now consider a 700C rim with the same height as a 20-inch rim.
If you build this rim with nupoke radial lacing,
the spoke becomes the red dashed line in the diagram above.
If you want the spoke angle the spokes form (the blue angle in the diagram above)
to be roughly the same when building the 20-inch rim,
you'd need to move the hub flange inward.
This is why the Systema hub suits small-wheeled bikes.
Building a 700C rim with anti-nupoke from that configuration
creates the best front wheel aerodynamically (as a spoked wheel),
frontal projection area-wise. That's what I was aiming for with my front wheel.
You're welcome to order Tni AL300 rims laced nupoke radial,
but for various reasons I wouldn't recommend it.
(It's not impossible.)
If you ask why I built the Envé 45 with nupoke then,
well, there are reasons I can't write about here, so that's awkward...
Today's story was "radial lacing comes in two types."
Today's topic is about spoke routing when doing radial lacing.
First, let me explain since it's been a while.
On this blog, we call spokes that thread from inside the hub flange to outside
"nupoke,"
and spokes that thread from outside the hub flange to inside
"anti-nupoke."
↑In tangential lacing, the spokes threaded through the flange alternate between nupoke and anti-nupoke,
but in radial lacing they consist of only one type or the other.
↑This is a Shimano WH-R501, laced radially with anti-nupoke spokes.
Nearly all complete wheelsets using butted spokes in radial lacing are built with "anti-nupoke radial" lacing,
with only very rare exceptions.
The Tni wheel I mentioned yesterday (thanks for all the inquiries) was also
built as anti-nupoke radial, keeping it understated since it's a stock wheel.
Though I said "keeping it understated," I sometimes build wheels in "nupoke radial" lacing.
This isn't a common lacing method, but compared to anti-nupoke radial,
it has both advantages and disadvantages. After weighing these,
I choose nupoke radial when it seems more beneficial.
Whether nupoke or anti-nupoke, I base lateral stiffness calculations on the root of the spoke,
in other words where the spoke emerges from the hub flange.
Anti-nupoke has a narrower base, so it has inferior lateral stiffness
compared to nupoke (in my assessment).
This is the structural stiffness characteristic of anti-nupoke radial lacing, but
let's also consider the aerodynamic side.
Though the rim-side portion of the spoke is hidden by the rim and tire,
anti-nupoke radial has a smaller frontal projection area,
making it aerodynamically advantageous.
In nupoke radial lacing, compared to anti-nupoke radial,
more of the spoke is exposed beyond the rim or tire.
Aerodynamically at a disadvantage. However, since the spoke's deflection starting point
is a wider span, it's advantageous in lateral stiffness.
Additionally, with anti-nupoke, the spoke neck opens outward as it leaves the flange.
With nupoke, by contrast, it bends inward, and
nupoke spokes are less prone to spoke breakage at the neck.
This is the biggest reason I build wheels with nupoke radial lacing.
Some complete wheelsets with butted spokes have extremely thick flanges
and use custom-length spokes fitted to match, reducing spoke breakage risk
in anti-nupoke radial lacing.
Rolf Prima is an example of this.
They use custom White Industries hubs (with custom phase angles for paired spokes)
paired with custom-dimension Sapim spokes—quite thorough.
The (likely main) reason manufacturers avoid nupoke radial lacing is the risk of spoke-to-hub-flange interference,
depending on flange shape (especially height). The kind of contact shown above
never occurs with anti-nupoke radial lacing.
The severity of this problem varies with rim height.
With low rims, nupoké spokes angle steeply toward the rim,
making flange contact less likely, but
as the rim gets taller, spoke angle flattens, causing flange contact problems.
Even when I want nupoke radial, if the rim is tall I often give up
and go with anti-nupoke radial instead.
Same rim height, but the 45mm from the Edge era and the 45mm from Envé.
I'm building these at this rim height with nupoke radial lacing.
↑My mysterious Cosmic Carbon wheel also has the non-drive-side radial laced as nupoke.
A wheel being temporarily built with nupoke radial lacing
has spokes that bulge outward.
Unrelated note, but the hub is a Suntour Superior Pro.
Before building
After building
On a different topic,
I'm often asked about the stiffness feel of Tni AL300 rim wheels.
I don't know.
So I built a front wheel for myself.
This is also nupoke radial lacing.
The hub is a White Industries H-2,
and the spokes are Sapim CX-RAY.
The top of the image is the direction of travel.
The hub lettering ends up backward, but that's intentional. I'll explain why later.
Of course it's also possible to build yesterday's Nomu Lab wheel with CX-RAY spokes,
at an upcharge of ¥5,000 per wheel (for 20H).
For 24H it's ¥6,000 upcharge.
I chose this hub for a reason:
the hub flange isn't perfectly straight.
↑Exaggerated a lot, it's something like this.
I chose it because it doesn't seem prone to flange contact problems.
Unrelated to nupoke, but...
This time I built the wheel with the image top being the direction of travel.
This makes the lettering read backward.
I think the correct orientation is having the hub adjustment grub screw hole
on the left side facing forward, but doing so makes the lettering backward.
Still, I believe this is the correct way.
On rear hubs, this grub screw hole is on the left side.
(The right has the freewheel body, so that's impossible.)
Thinking "adjustment mechanism on the left for both front and rear,"
it should be this way. There's another hub from a different manufacturer
that supports this theory.
↑This is a rear hub from a manufacturer called Extralite.
The adjustment mechanism is naturally on the left side.
A file-marked dial-like feature is attached to the left side of the hub body.
And this is a front hub, which has the same file-marked dial
on the right side (when looking from the direction text reads).
However, the hub body has "LeftSide>>" explicitly noted, so
they're saying to build it in this orientation.
The rear hub logo reads forward with travel direction, while the front hub reads backward.
I determined the White H-2 hub follows the same logic,
so I built it the way that looks backward at first glance.
My 4820g Akamatsu aluminum bike has a front wheel built with
an Akamatsu Systema hub.
While there are lighter hubs available, I chose this one because I wanted it,
prioritizing my preference over weight.
It's a truly excellent hub. Alright, I'll say it.
This is just shameless promotion of the Systema hub.
...Sorry. Please ignore that.
The flange width is narrow, so lateral stiffness is structurally limited,
but you don't notice it unless you're standing on the pedals hard.
Since the flange is already narrow, rather than trying to boost lateral stiffness
with nupoke radial, I'm aiming for ultimate minimal spoke frontal projection area
with anti-nupoke radial.
Narrow! Aerodynamically it's a pretty tasty front wheel.
With the White H-2 hub it looks like this.
Since the H-2 has quite wide flanges, these two wheels
represent the opposite extremes of radial lacing.
The reason the Systema hub has a narrow flange is
because it's also designed for use on small-wheeled bikes.
When calculated, a 700C rim with the same inner diameter as a 20-inch (HE) small-wheel rim
would be approximately 90mm in rim height.
If you build that rim with nupoke radial lacing, spoke angle becomes quite steep,
making flange contact problems more likely.
Or even with tangential lacing, half the spokes are nupoke.
With tangential lacing plus woven spoke intersections, the angle at which
nupoke emerges from the flange becomes steeper than radial lacing.
Now consider a 700C rim with the same height as a 20-inch rim.
If you build this rim with nupoke radial lacing,
the spoke becomes the red dashed line in the diagram above.
If you want the spoke angle the spokes form (the blue angle in the diagram above)
to be roughly the same when building the 20-inch rim,
you'd need to move the hub flange inward.
This is why the Systema hub suits small-wheeled bikes.
Building a 700C rim with anti-nupoke from that configuration
creates the best front wheel aerodynamically (as a spoked wheel),
frontal projection area-wise. That's what I was aiming for with my front wheel.
You're welcome to order Tni AL300 rims laced nupoke radial,
but for various reasons I wouldn't recommend it.
(It's not impossible.)
If you ask why I built the Envé 45 with nupoke then,
well, there are reasons I can't write about here, so that's awkward...
Today's story was "radial lacing comes in two types."