A customer dropped off a
CADEX (carbon spoke wheel brand) wheel with carbon spokes for us to look at.
Starting with the rear wheel.
The wheel was purchased at a GIANT store,
and a nearby Wise Road shop
replaced the bearings with Oni bearings (JTEKT ceramic bearings).
The customer asked us to inspect it and verify
that the bearings were pressed in correctly.
Since I'm the one who started this whole thing, I can't back out now.
Of the DBL (dished brake left) designs, we've discontinued the spoke weight DBL,
but we continue to use DBL at the spoke head positions on the hub flanges.
The image above shows the anti-freewheel side,
where the nipple positions of the final crossing spokes
are arranged in a "single flange high-low flange" pattern.
The freewheel side is a bit harder to see, but
you can tell the hub has DBL because
identical-sized nipples protrude more from the flange only on the anti-porcupine side,
and a radial line from the hub center passing through the midpoint between the two nipples
of the final crossing spokes clearly doesn't pass through the final crossing itself.
Apart from this hub DBL design, the CADEX wheel
is actually quite well made with hardly any flaws.
Though the downside might be that it's "a bit too stiff."
There's a slight centering offset,
but there was one spot with a pretty bad wobble,
and if I'd deliberately checked at that exact spot,
I might have been able to show an even larger offset amount.
I trued the wheel and corrected the center.
Before that, I checked the bearing press-fit condition
and found no problems.
Next, the front wheel.
Ah, so that's what it was!
When I press both ends of the hub with my thumbs,
there's lateral play with a clicking sound.
Since the customer wrote in their request
"Please verify the bearing press-fit is correct,"
they probably already noticed this play.
You can feel it with just the wheel in hand,
but when it's mounted in the fork,
you'll definitely feel the lateral play even when gripping the rim,
and it might also show up in disc brake adjustments.
I thought about calling the customer to see if they'd noticed,
but I just fixed it first.
The clicking sound from the hub play is loud enough
to hear clearly over the phone.
↑Like this
The left side has the larger bearing with higher contact pressure around the circumference,
so unless the hub body's tolerance is smaller on the smaller bearing side
or the press-fit is particularly stiff,
the smaller bearing presses in first and fully seats.
When both left and right bearings are fully pressed in,
the spacing between the inner races of the two bearings
and the spacing of the inner race seats on the hub shaft should match.
But since the press-fit isn't complete,
the hub shaft gets lateral play by that amount.
In the diagram above I've exaggerated the gap
of the incomplete press-fit, but—
I laid the wheel on its side and
pushed the left end as far as possible toward the bottom of the image (right side of wheel),
as shown above.
Then I pushed the right end from below and
moved the hub shaft all the way to the top,
as shown here.
Hmm, it's hard to see.
You can barely make out the difference in the step gap
between the edge of the left end cap and the hub flange.
The lateral play is quite substantial,
so if I'd done this more carefully
I might have captured a clearer difference.
I measured the left end dimension with a center gauge.
Naturally, there's no gap.
This wasn't to check the temporary wheel center,
but based on my prediction that the press-fit is insufficient
only on the left side, or mainly on the left,
to record the left end position before the re-pressing work.
Oni bearings are ceramic bearings from JTEKT (Japan Technology Corporation),
a bearing maker, made for high-end sports bikes.
Installation is only permitted at certified shops that have received training,
and the bearings are not sold as individual parts—
they come with installation labor included, no discounts allowed,
with a manufacturer-specified retail price.
But in this case, the idiot Wise Road staff didn't press them in fully,
so I had to do it.
Technically I should have told the customer
"Please have Wise Road look at it again,"
but the hassle of having to inspect the wheel again at our shop
after another visit to Wise Road would be enormous,
so I re-pressed the bearings.
I say "re-pressed," but I didn't remove the bearings—
I just set up the tool and applied pressure to the current state.
It went in more than I expected.
The center gauge reading stayed the same of course,
and while the front wheel didn't have as much runout as the rear,
I've adjusted the rim phase to be nearly the same for center gauge contact.
The lateral play in the hub shaft is now gone.
↑This is after re-pressing,
but I should have taken a close-up of the bearing position before re-pressing
after wiping off the grease.
Both front and rear hubs had grease slathered
between the end cap and bearing seal,
whether that's a quirk of the Wise Road staff
or something specified by Oni bearings, I don't know.
I cleared the saved measurement from the center gauge
and checked the temporary center again.
The rim is offset to the left.
This should be the same state as before the bearing swap.
Based on the direction of the offset,
it's possible that Wise Road did the truing and centering
with insufficient bearing press-fit,
but that doesn't explain why the front wheel had
lateral wobble—something that would be obvious on a truing stand—
so all Wise Road really did was a half-hearted bearing press job.
Incidentally, the amount the bearing moved during re-pressing
is slightly less than the existing centering offset.
I did very minor truing and centering adjustments.
According to the customer, when GIANT store took this wheel out of the box,
they said "It's new so it's fine,"
which is technically not wrong, just imprecise.
"It's new and has passed the manufacturer's quality check so it's fine,
and since we lack both the willingness and the technical ability
to improve it beyond factory condition,
all we can do is hand it over as-is from one side to the other.
Don't ask stupid questions, you fool."
—they were just being a bit terse in how they put it.
Earlier I mentioned that Oni bearings come with a manufacturer-set price including labor,
but there's actually a distributor between JTEKT and the retailers,
and it's the distributor who handles shop certification
and sets the prices.
How can I be sure of this? Because
someone from JTEKT visited our shop and I asked them.
At that time, they asked if we had any bikes
actually equipped with Oni bearings on both wheels and BBs—
not just a drivetrain sample unit—
and if so, they'd like to see one.
In return, I said I had something I'd like to show them too,
but it still hasn't happened.
Maybe they had a bad feeling about it.
...They've got good instincts.
CADEX (carbon spoke wheel brand) wheel with carbon spokes for us to look at.
Starting with the rear wheel.
The wheel was purchased at a GIANT store,
and a nearby Wise Road shop
replaced the bearings with Oni bearings (JTEKT ceramic bearings).
The customer asked us to inspect it and verify
that the bearings were pressed in correctly.
Since I'm the one who started this whole thing, I can't back out now.
Of the DBL (dished brake left) designs, we've discontinued the spoke weight DBL,
but we continue to use DBL at the spoke head positions on the hub flanges.
The image above shows the anti-freewheel side,
where the nipple positions of the final crossing spokes
are arranged in a "single flange high-low flange" pattern.
The freewheel side is a bit harder to see, but
you can tell the hub has DBL because
identical-sized nipples protrude more from the flange only on the anti-porcupine side,
and a radial line from the hub center passing through the midpoint between the two nipples
of the final crossing spokes clearly doesn't pass through the final crossing itself.
Apart from this hub DBL design, the CADEX wheel
is actually quite well made with hardly any flaws.
Though the downside might be that it's "a bit too stiff."
There's a slight centering offset,
but there was one spot with a pretty bad wobble,
and if I'd deliberately checked at that exact spot,
I might have been able to show an even larger offset amount.
I trued the wheel and corrected the center.
Before that, I checked the bearing press-fit condition
and found no problems.
Next, the front wheel.
Ah, so that's what it was!
When I press both ends of the hub with my thumbs,
there's lateral play with a clicking sound.
Since the customer wrote in their request
"Please verify the bearing press-fit is correct,"
they probably already noticed this play.
You can feel it with just the wheel in hand,
but when it's mounted in the fork,
you'll definitely feel the lateral play even when gripping the rim,
and it might also show up in disc brake adjustments.
I thought about calling the customer to see if they'd noticed,
but I just fixed it first.
The clicking sound from the hub play is loud enough
to hear clearly over the phone.
↑Like this
The left side has the larger bearing with higher contact pressure around the circumference,
so unless the hub body's tolerance is smaller on the smaller bearing side
or the press-fit is particularly stiff,
the smaller bearing presses in first and fully seats.
When both left and right bearings are fully pressed in,
the spacing between the inner races of the two bearings
and the spacing of the inner race seats on the hub shaft should match.
But since the press-fit isn't complete,
the hub shaft gets lateral play by that amount.
In the diagram above I've exaggerated the gap
of the incomplete press-fit, but—
I laid the wheel on its side and
pushed the left end as far as possible toward the bottom of the image (right side of wheel),
as shown above.
Then I pushed the right end from below and
moved the hub shaft all the way to the top,
as shown here.
Hmm, it's hard to see.
You can barely make out the difference in the step gap
between the edge of the left end cap and the hub flange.
The lateral play is quite substantial,
so if I'd done this more carefully
I might have captured a clearer difference.
I measured the left end dimension with a center gauge.
Naturally, there's no gap.
This wasn't to check the temporary wheel center,
but based on my prediction that the press-fit is insufficient
only on the left side, or mainly on the left,
to record the left end position before the re-pressing work.
Oni bearings are ceramic bearings from JTEKT (Japan Technology Corporation),
a bearing maker, made for high-end sports bikes.
Installation is only permitted at certified shops that have received training,
and the bearings are not sold as individual parts—
they come with installation labor included, no discounts allowed,
with a manufacturer-specified retail price.
But in this case, the idiot Wise Road staff didn't press them in fully,
so I had to do it.
Technically I should have told the customer
"Please have Wise Road look at it again,"
but the hassle of having to inspect the wheel again at our shop
after another visit to Wise Road would be enormous,
so I re-pressed the bearings.
I say "re-pressed," but I didn't remove the bearings—
I just set up the tool and applied pressure to the current state.
It went in more than I expected.
The center gauge reading stayed the same of course,
and while the front wheel didn't have as much runout as the rear,
I've adjusted the rim phase to be nearly the same for center gauge contact.
The lateral play in the hub shaft is now gone.
↑This is after re-pressing,
but I should have taken a close-up of the bearing position before re-pressing
after wiping off the grease.
Both front and rear hubs had grease slathered
between the end cap and bearing seal,
whether that's a quirk of the Wise Road staff
or something specified by Oni bearings, I don't know.
I cleared the saved measurement from the center gauge
and checked the temporary center again.
The rim is offset to the left.
This should be the same state as before the bearing swap.
Based on the direction of the offset,
it's possible that Wise Road did the truing and centering
with insufficient bearing press-fit,
but that doesn't explain why the front wheel had
lateral wobble—something that would be obvious on a truing stand—
so all Wise Road really did was a half-hearted bearing press job.
Incidentally, the amount the bearing moved during re-pressing
is slightly less than the existing centering offset.
I did very minor truing and centering adjustments.
According to the customer, when GIANT store took this wheel out of the box,
they said "It's new so it's fine,"
which is technically not wrong, just imprecise.
"It's new and has passed the manufacturer's quality check so it's fine,
and since we lack both the willingness and the technical ability
to improve it beyond factory condition,
all we can do is hand it over as-is from one side to the other.
Don't ask stupid questions, you fool."
—they were just being a bit terse in how they put it.
Earlier I mentioned that Oni bearings come with a manufacturer-set price including labor,
but there's actually a distributor between JTEKT and the retailers,
and it's the distributor who handles shop certification
and sets the prices.
How can I be sure of this? Because
someone from JTEKT visited our shop and I asked them.
At that time, they asked if we had any bikes
actually equipped with Oni bearings on both wheels and BBs—
not just a drivetrain sample unit—
and if so, they'd like to see one.
In return, I said I had something I'd like to show them too,
but it still hasn't happened.
Maybe they had a bad feeling about it.
...They've got good instincts.