The other day, I wrote about the naming conventions for Princeton Carbon Works wheels
(→here),
and when I mentioned that Princeton didn't make tubular models,
I received a comment from someone who actually owns
a PEAK4550 with a tubular rim specification.
After investigating, I confirmed that both the PEAK4550 and
ALTA3532 currently offer tubular rim options.
↑This is the specification selection screen for the
WAKE6560 from the manufacturer's direct sales site.
You choose your preferred spec from four categories:
brake type, hub manufacturer,
freebody standard, and rim finish.
↑This is the PEAK4550 screen. Unlike the WAKE6560,
there's an additional "tire bed" category
where you can choose between
"clincher tubeless ready" and
"tubular."
By the way, the last finish category on the PEAK4550
lets you select from rim surface finish and text/marking color:
matte finish / black text
matte finish / white text
gloss finish / gold text
gloss finish / chrome text
While investigating, I came across another question
and dug deeper into it.
It turns out rim brake models have a 16H front wheel specification.
Princeton's jagged rims set the rim holes at the sharp peaks of the waves
(same as with ZIPP wheels, by the way).
You might think they'd design 16-wave rims for 16H wheels,
but to save on tooling costs, the company only manufactures 24-wave rims.
Campagnolo does something similar—the Bora WTO disc brake version
and Bora WTO Ultra (disc brake only)
are both 24H front and rear, sharing the same rim.
Particularly with Bora WTO Ultra, which uses ENVE-style molding
with rim holes already drilled during manufacturing,
changing the hole count requires separate tooling.
The Bora WTO rim brake wheels have
18H front and 21H rear,
but there's no Ultra version because they probably decided
it would be difficult to recoup tooling costs on rim brake wheels.
Hyperion Ultra, which like Bora WTO Ultra
uses "internal nipples driven from the inside,"
has 21H front and 24H rear, and apparently because
they can't share tooling anyway,
the rear rim alone is offset.
Now, if both wheels were 24H,
could they share tooling? Well, if you drill the rim holes afterward, yes.
But with Hyperion Ultra,
the rear wheel uses tangent lacing on both sides, so
trying to have radial lacing on the front only while keeping the same
rim hole orientation and using special internal nipples
seems impossible.
I've never tried it, but offsetting the rim holes and hub relationship
by just one or three holes on Hyperion Ultra's rear wheel,
accepting that the valve hole phase ends up odd,
would probably also be impossible.
So, how did Princeton solve the problem of
wanting to offer a 16H front wheel
while only manufacturing 24-wave rims for cost reasons?
I've drawn 12 waves—half of the 24-wave circumference.
At the peaks of these 12 waves, you can position
8 spokes (the blue lines in the diagram above)
on one side of a normal 16H hub
with even spacing.
Next, assuming a standard 16H hub
with the other flange holes drilled at the midpoint phase,
if I add the spoke paths (the red lines in the diagram),
↑you get this.
The red spokes would land in the wave valleys on the rim side,
making it impossible to build the wheel.
So, I rotate the red spoke flange,
making it nearly pair-spoke arrangement,
positioning the red spokes to land at wave peaks—
that's Princeton's 16H rim brake front wheel.
This isn't simply a matter of eliminating spokes from a 24H wheel.
↑The difference between normal 24H and
24H rim with phase-offset 16H hub
The holes alternate between matching and not matching the original hole positions.
Either way, since it's radial lacing,
the rim holes probably have no front-back directionality, but
if there is left-right hole orientation,
you couldn't add holes to Princeton's 16H rim
to use it as a 24H. Well, maybe if you make the resting phase
match the multi-spoke side holes,
you could create a 2:1-specific 24H rim.
The person in the original comment said they "had" a PEAK4550
in the past tense because they felt
16H lacked sufficient stiffness
and sold it. They also mentioned,
"It would be simpler to just go 24H."
24 has many divisors, but if you're reducing rim holes evenly
or so that the sparse and dense spacing are equal
with equal numbers on both sides (which is pair-spoking),
besides the 1/2 option giving 12H,
the 2/3 option giving around 16H
is really the only practical choice.
Anyway, thanks for the comment.
(→here),
and when I mentioned that Princeton didn't make tubular models,
I received a comment from someone who actually owns
a PEAK4550 with a tubular rim specification.
After investigating, I confirmed that both the PEAK4550 and
ALTA3532 currently offer tubular rim options.
↑This is the specification selection screen for the
WAKE6560 from the manufacturer's direct sales site.
You choose your preferred spec from four categories:
brake type, hub manufacturer,
freebody standard, and rim finish.
↑This is the PEAK4550 screen. Unlike the WAKE6560,
there's an additional "tire bed" category
where you can choose between
"clincher tubeless ready" and
"tubular."
By the way, the last finish category on the PEAK4550
lets you select from rim surface finish and text/marking color:
matte finish / black text
matte finish / white text
gloss finish / gold text
gloss finish / chrome text
While investigating, I came across another question
and dug deeper into it.
It turns out rim brake models have a 16H front wheel specification.
Princeton's jagged rims set the rim holes at the sharp peaks of the waves
(same as with ZIPP wheels, by the way).
You might think they'd design 16-wave rims for 16H wheels,
but to save on tooling costs, the company only manufactures 24-wave rims.
Campagnolo does something similar—the Bora WTO disc brake version
and Bora WTO Ultra (disc brake only)
are both 24H front and rear, sharing the same rim.
Particularly with Bora WTO Ultra, which uses ENVE-style molding
with rim holes already drilled during manufacturing,
changing the hole count requires separate tooling.
The Bora WTO rim brake wheels have
18H front and 21H rear,
but there's no Ultra version because they probably decided
it would be difficult to recoup tooling costs on rim brake wheels.
Hyperion Ultra, which like Bora WTO Ultra
uses "internal nipples driven from the inside,"
has 21H front and 24H rear, and apparently because
they can't share tooling anyway,
the rear rim alone is offset.
Now, if both wheels were 24H,
could they share tooling? Well, if you drill the rim holes afterward, yes.
But with Hyperion Ultra,
the rear wheel uses tangent lacing on both sides, so
trying to have radial lacing on the front only while keeping the same
rim hole orientation and using special internal nipples
seems impossible.
I've never tried it, but offsetting the rim holes and hub relationship
by just one or three holes on Hyperion Ultra's rear wheel,
accepting that the valve hole phase ends up odd,
would probably also be impossible.
So, how did Princeton solve the problem of
wanting to offer a 16H front wheel
while only manufacturing 24-wave rims for cost reasons?
I've drawn 12 waves—half of the 24-wave circumference.
At the peaks of these 12 waves, you can position
8 spokes (the blue lines in the diagram above)
on one side of a normal 16H hub
with even spacing.
Next, assuming a standard 16H hub
with the other flange holes drilled at the midpoint phase,
if I add the spoke paths (the red lines in the diagram),
↑you get this.
The red spokes would land in the wave valleys on the rim side,
making it impossible to build the wheel.
So, I rotate the red spoke flange,
making it nearly pair-spoke arrangement,
positioning the red spokes to land at wave peaks—
that's Princeton's 16H rim brake front wheel.
This isn't simply a matter of eliminating spokes from a 24H wheel.
↑The difference between normal 24H and
24H rim with phase-offset 16H hub
The holes alternate between matching and not matching the original hole positions.
Either way, since it's radial lacing,
the rim holes probably have no front-back directionality, but
if there is left-right hole orientation,
you couldn't add holes to Princeton's 16H rim
to use it as a 24H. Well, maybe if you make the resting phase
match the multi-spoke side holes,
you could create a 2:1-specific 24H rim.
The person in the original comment said they "had" a PEAK4550
in the past tense because they felt
16H lacked sufficient stiffness
and sold it. They also mentioned,
"It would be simpler to just go 24H."
24 has many divisors, but if you're reducing rim holes evenly
or so that the sparse and dense spacing are equal
with equal numbers on both sides (which is pair-spoking),
besides the 1/2 option giving 12H,
the 2/3 option giving around 16H
is really the only practical choice.
Anyway, thanks for the comment.