I received a customer's CADEX front and rear wheels on deposit.
The image above is the rear wheel.
I forgot to take an overall shot of the front wheel.
Both front and rear wheel hubs have gotten quite rough when rotating,
so the customer wants the bearings replaced.
We'll be using Japanese-made bearings with non-contact seals,
which the customer approved.
I didn't photograph it in the clearest way possible,
but the hub's DBL (double bearing lateral) setup
somehow remains—once you start something you can't easily back out of it, I guess.
Apart from that, it's an excellent wheel.
Some people might say it's unnecessarily stiff,
but there are countless wheels priced higher than this one
that don't perform as well.
↑The left side of the rear wheel hub body.
Shimano's 10-speed sprocket 1mm low spacers
fit perfectly onto single freewheel threads,
so they can be repurposed when you want to move the freewheel outward.
Boss freewheel thread diameter matches
BSC bottom bracket thread diameter,
so they work as spacers for BSC bottom brackets too.
What I'm getting at is this:
the outer diameter of the high points on Shimano's freebody spline
is matched to the threads of older boss freewheels.
Shimano, which developed the HG freebody system,
doesn't use cartridge bearings in their freebody
(except for 7800 series Dura-Ace rear hubs),
but when third-party manufacturers
make cartridge bearing rear hubs,
it's unthinkable to commission custom bearings
to match the freebody.
So from standard bearing sizes, they chose one that fits:
a 6000 bearing with 10mm inner diameter to match a 10mm steel shaft,
26mm outer diameter, and 8mm width.
Later, when 15mm aluminum shafts became the standard
for cartridge bearing rear hub axles,
6902 bearings came into use—
15mm inner diameter, 28mm outer diameter, 7mm width.
Since this 28mm outer diameter is just slightly smaller
than Shimano's HG freebody lockring thread diameter, it fits the freebody,
but the dimensional clearance between the bearing outer diameter
and the outer diameter of the freebody spline valleys is so tight
that a non-standard 15267 bearing was created—
same 2mm smaller outer diameter as 6000 but from 6902—
to meet demand from the sports cycling industry.
This is just a number expressed by listing the dimensions:
15mm inner diameter, 26mm outer diameter, 7mm width.
Following that convention, 6902 would be 15287.
I said earlier it's unthinkable to commission custom bearings for the freebody,
but because demand was so massive,
the 15267 bearing was born.
Aluminum hub axles usually have 15mm outer diameter,
but because the 6802 standard bearing existed—
15245, a smaller 15mm inner diameter option—
it sometimes gets used instead of 15267 or 15287 (6902)
as a somewhat stingy weight-saving measure.
Though you probably can't see them anymore,
the bearings in the image above are like that too.
Compared to 6902, the 6802 has the same inner diameter but 4mm smaller outer diameter,
so the steel balls inside are smaller, and durability is clearly lower.
Roval's front wheel also uses 6802 bearings on both sides,
and they're usually fixed to Specialized forks,
but Specialized's through-axle X-12 standard
is particularly tight-fitting,
so bearing damage from over-tightening the through-axle
is extremely common.
The bearing on the outside of the freebody
with the same diameter lockring threads.
This one is also 6802, and rust has set in.
The hub body side after removing the freebody.
The pawl ratchet is single-acting with the spring only on the freebody side,
so when rust sets in on the hub body side pawl ratchet part,
it often becomes difficult to remove.
Only the hub body right side has a 6902 bearing,
and of the six total bearings across both wheels,
that one seemed like it could continue being used,
but since there was no complete absence of wear,
I replaced all the bearings.
The freebody side pawl ratchet has a spring,
so it gets pushed out by the freebody,
but that movement was sluggish due to rust.
If rust becomes so bad the spring can't lift it,
there's a non-zero chance the freebody would freewheel in the forward direction.
Both of the freebody bearings are 6802,
with a tall spacer sandwiched between them to support the bearing inner races,
but the bearings aren't both press-fit from the outside—
the inner bearing is press-fit from the inside instead.
With this type of freebody, if the hub axle and right end
have a threaded relationship,
the inner bearing can fall out,
but the right end is just a press-fit cap with no play
in the freebody side-to-side, so maybe that was judged as fine.
I removed the hub body side pawl ratchet part.
The hub body right side is a 6902 bearing.
By the way, the front wheel left side—
the centerlock rotor mounting side bearing—was also 6902.
So 6902 does fit after all.
After cleaning all the parts and replacing the bearings, I reassembled and applied
dedicated grease to the pawl ratchets.
I applied oil between the freebody side pawl ratchet part and the freebody
to lighten the spring action.
Both wheels are nearly true
and centered perfectly,
but I noticed several nipples on the rear wheel with traces of having been touched,
so I asked the customer
and they mentioned there was a history of spoke replacements.
The image above is the rear wheel.
I forgot to take an overall shot of the front wheel.
Both front and rear wheel hubs have gotten quite rough when rotating,
so the customer wants the bearings replaced.
We'll be using Japanese-made bearings with non-contact seals,
which the customer approved.
I didn't photograph it in the clearest way possible,
but the hub's DBL (double bearing lateral) setup
somehow remains—once you start something you can't easily back out of it, I guess.
Apart from that, it's an excellent wheel.
Some people might say it's unnecessarily stiff,
but there are countless wheels priced higher than this one
that don't perform as well.
↑The left side of the rear wheel hub body.
Shimano's 10-speed sprocket 1mm low spacers
fit perfectly onto single freewheel threads,
so they can be repurposed when you want to move the freewheel outward.
Boss freewheel thread diameter matches
BSC bottom bracket thread diameter,
so they work as spacers for BSC bottom brackets too.
What I'm getting at is this:
the outer diameter of the high points on Shimano's freebody spline
is matched to the threads of older boss freewheels.
Shimano, which developed the HG freebody system,
doesn't use cartridge bearings in their freebody
(except for 7800 series Dura-Ace rear hubs),
but when third-party manufacturers
make cartridge bearing rear hubs,
it's unthinkable to commission custom bearings
to match the freebody.
So from standard bearing sizes, they chose one that fits:
a 6000 bearing with 10mm inner diameter to match a 10mm steel shaft,
26mm outer diameter, and 8mm width.
Later, when 15mm aluminum shafts became the standard
for cartridge bearing rear hub axles,
6902 bearings came into use—
15mm inner diameter, 28mm outer diameter, 7mm width.
Since this 28mm outer diameter is just slightly smaller
than Shimano's HG freebody lockring thread diameter, it fits the freebody,
but the dimensional clearance between the bearing outer diameter
and the outer diameter of the freebody spline valleys is so tight
that a non-standard 15267 bearing was created—
same 2mm smaller outer diameter as 6000 but from 6902—
to meet demand from the sports cycling industry.
This is just a number expressed by listing the dimensions:
15mm inner diameter, 26mm outer diameter, 7mm width.
Following that convention, 6902 would be 15287.
I said earlier it's unthinkable to commission custom bearings for the freebody,
but because demand was so massive,
the 15267 bearing was born.
Aluminum hub axles usually have 15mm outer diameter,
but because the 6802 standard bearing existed—
15245, a smaller 15mm inner diameter option—
it sometimes gets used instead of 15267 or 15287 (6902)
as a somewhat stingy weight-saving measure.
Though you probably can't see them anymore,
the bearings in the image above are like that too.
Compared to 6902, the 6802 has the same inner diameter but 4mm smaller outer diameter,
so the steel balls inside are smaller, and durability is clearly lower.
Roval's front wheel also uses 6802 bearings on both sides,
and they're usually fixed to Specialized forks,
but Specialized's through-axle X-12 standard
is particularly tight-fitting,
so bearing damage from over-tightening the through-axle
is extremely common.
The bearing on the outside of the freebody
with the same diameter lockring threads.
This one is also 6802, and rust has set in.
The hub body side after removing the freebody.
The pawl ratchet is single-acting with the spring only on the freebody side,
so when rust sets in on the hub body side pawl ratchet part,
it often becomes difficult to remove.
Only the hub body right side has a 6902 bearing,
and of the six total bearings across both wheels,
that one seemed like it could continue being used,
but since there was no complete absence of wear,
I replaced all the bearings.
The freebody side pawl ratchet has a spring,
so it gets pushed out by the freebody,
but that movement was sluggish due to rust.
If rust becomes so bad the spring can't lift it,
there's a non-zero chance the freebody would freewheel in the forward direction.
Both of the freebody bearings are 6802,
with a tall spacer sandwiched between them to support the bearing inner races,
but the bearings aren't both press-fit from the outside—
the inner bearing is press-fit from the inside instead.
With this type of freebody, if the hub axle and right end
have a threaded relationship,
the inner bearing can fall out,
but the right end is just a press-fit cap with no play
in the freebody side-to-side, so maybe that was judged as fine.
I removed the hub body side pawl ratchet part.
The hub body right side is a 6902 bearing.
By the way, the front wheel left side—
the centerlock rotor mounting side bearing—was also 6902.
So 6902 does fit after all.
After cleaning all the parts and replacing the bearings, I reassembled and applied
dedicated grease to the pawl ratchets.
I applied oil between the freebody side pawl ratchet part and the freebody
to lighten the spring action.
Both wheels are nearly true
and centered perfectly,
but I noticed several nipples on the rear wheel with traces of having been touched,
so I asked the customer
and they mentioned there was a history of spoke replacements.