The other day, I had to replace the freebody on the rear wheel hub made in-house by Schmolke with a SRAM XDR freebody.
↑Removed the Shimano 11-speed version.
↑This is the SRAM XDR version.
The freebody has a warning: "Do not use in combinations lighter than a 1:1 gear ratio."
It's unclear whether that means "less than" or "equal to or less than,"
but if it's the latter, then a 34T front chainring × 34T low gear would be forbidden.
The manufacturer is concerned about pedaling torque,
so the issue is that the chain's driving torque gets transmitted to the large-radius gear
mounted deep inside the freebody.
If we had a 24T × 24T combination front and rear, would it really be a problem?
Or if it's 39T × 34T, that's over 1:1 ratio but might be risky?
I can't really think of clear counterexamples,
but this freebody is from Cyber (a road-focused brand),
so that first combination is ruled out anyway.
Anyway, about this freebody—
for some reason, it's missing three things: two pawls, a pawl-return spring (an O-ring), and a waterproof O-ring that goes over the green anodized section.
And on top of that, a mysterious part labeled "60 P.O.E." was included.
I thought, what the heck is this? After investigating, I found out
it was a manufacturer packaging error.
↑This is an image from the manufacturer's site,
showing the freebody of a hub called Hyper (designed for MTB).
The Hyper's ratchet section doesn't use a pawl spring like the Cyber does;
instead it uses a face ratchet like DT's star ratchet,
and P.O.E. is an acronym for "Points of Engagement,"
referring to the number of teeth on the face ratchet.
So what happened was that the Cyber freebody (with missing parts) received
hub-side parts from the Hyper instead—a manufacturer error.
Looking at the manufacturer's site, the Hyper doesn't have an XDR freebody,
only XD for MTB use.
Conversely, until recently the Cyber didn't have an XDR freebody either,
so XD-format freebodies only existed for the Hyper.
It's likely that someone at the manufacturer's hand
instinctively remembered the routine of "when packing an XD-format freebody, include the face ratchet ring too"
and made this mistake.
The bag says it's for Cyber,
so having Hyper parts in there is definitely wrong.
↑60-point face ratchet
↑The job that DT's star ratchet accomplishes with a "bamboo shoot spring"
is being done here by three wimpy little coil springs.
And whereas the old star ratchet had two bamboo shoot springs
on the left and right sides of the ratchet,
this one is single-action (no spring on the freebody side),
so it's quite an aggressive design.
Crazy, right?
↑I wrote the same thing last time when the pawl-return spring was a rubber O-ring,
but just to be clear, that's meant as praise.
Mavic's FTS-L freebody also has coil springs this size for its two-pawl return on the hub body side,
but those springs feel surprisingly strong for their size.
These three springs, though, have weak, mushy rebound from compression.
As for the Hyper freebody, the manufacturer's site currently lists five versions:
36-point XD, 60-point XD, 60-point Shimano 11-speed, 60-point Shimano 12-speed, and 45-point Shimano 11-speed road.
The 60-point Shimano 12-speed version uses microspline, but
the lockring that comes with it is an Extralight product
and must be tightened to only 12 Nm—
they specify not to use Shimano's genuine lockring.
For reference, the specified torque for Shimano's genuine microspline hub with
Shimano's genuine lockring is 30–50 Nm.
The only road version that exists is the 45-point,
and it's limited to use only with 142mm through-axles;
it's not to be used with 135mm or other widths
(they say it won't fit, though it's unclear if that's literally true).
Extralight's hubs have quite aggressive specs in terms of structure, materials, and dimensions,
but they also carefully document all the restrictions and warnings.
Anyway, regarding this situation,
the customer reported it to the distributor rather than the maker,
but since we couldn't wait for a replacement to arrive,
we ended up transferring the three missing parts from the Shimano freebody.
So, about the groove where this O-ring goes...
The inner lip seems way too thin.
Well, whatever.
↑Removed the Shimano 11-speed version.
↑This is the SRAM XDR version.
The freebody has a warning: "Do not use in combinations lighter than a 1:1 gear ratio."
It's unclear whether that means "less than" or "equal to or less than,"
but if it's the latter, then a 34T front chainring × 34T low gear would be forbidden.
The manufacturer is concerned about pedaling torque,
so the issue is that the chain's driving torque gets transmitted to the large-radius gear
mounted deep inside the freebody.
If we had a 24T × 24T combination front and rear, would it really be a problem?
Or if it's 39T × 34T, that's over 1:1 ratio but might be risky?
I can't really think of clear counterexamples,
but this freebody is from Cyber (a road-focused brand),
so that first combination is ruled out anyway.
Anyway, about this freebody—
for some reason, it's missing three things: two pawls, a pawl-return spring (an O-ring), and a waterproof O-ring that goes over the green anodized section.
And on top of that, a mysterious part labeled "60 P.O.E." was included.
I thought, what the heck is this? After investigating, I found out
it was a manufacturer packaging error.
↑This is an image from the manufacturer's site,
showing the freebody of a hub called Hyper (designed for MTB).
The Hyper's ratchet section doesn't use a pawl spring like the Cyber does;
instead it uses a face ratchet like DT's star ratchet,
and P.O.E. is an acronym for "Points of Engagement,"
referring to the number of teeth on the face ratchet.
So what happened was that the Cyber freebody (with missing parts) received
hub-side parts from the Hyper instead—a manufacturer error.
Looking at the manufacturer's site, the Hyper doesn't have an XDR freebody,
only XD for MTB use.
Conversely, until recently the Cyber didn't have an XDR freebody either,
so XD-format freebodies only existed for the Hyper.
It's likely that someone at the manufacturer's hand
instinctively remembered the routine of "when packing an XD-format freebody, include the face ratchet ring too"
and made this mistake.
The bag says it's for Cyber,
so having Hyper parts in there is definitely wrong.
↑60-point face ratchet
↑The job that DT's star ratchet accomplishes with a "bamboo shoot spring"
is being done here by three wimpy little coil springs.
And whereas the old star ratchet had two bamboo shoot springs
on the left and right sides of the ratchet,
this one is single-action (no spring on the freebody side),
so it's quite an aggressive design.
Crazy, right?
↑I wrote the same thing last time when the pawl-return spring was a rubber O-ring,
but just to be clear, that's meant as praise.
Mavic's FTS-L freebody also has coil springs this size for its two-pawl return on the hub body side,
but those springs feel surprisingly strong for their size.
These three springs, though, have weak, mushy rebound from compression.
As for the Hyper freebody, the manufacturer's site currently lists five versions:
36-point XD, 60-point XD, 60-point Shimano 11-speed, 60-point Shimano 12-speed, and 45-point Shimano 11-speed road.
The 60-point Shimano 12-speed version uses microspline, but
the lockring that comes with it is an Extralight product
and must be tightened to only 12 Nm—
they specify not to use Shimano's genuine lockring.
For reference, the specified torque for Shimano's genuine microspline hub with
Shimano's genuine lockring is 30–50 Nm.
The only road version that exists is the 45-point,
and it's limited to use only with 142mm through-axles;
it's not to be used with 135mm or other widths
(they say it won't fit, though it's unclear if that's literally true).
Extralight's hubs have quite aggressive specs in terms of structure, materials, and dimensions,
but they also carefully document all the restrictions and warnings.
Anyway, regarding this situation,
the customer reported it to the distributor rather than the maker,
but since we couldn't wait for a replacement to arrive,
we ended up transferring the three missing parts from the Shimano freebody.
So, about the groove where this O-ring goes...
The inner lip seems way too thin.
Well, whatever.