I received a Racing Zero rear wheel from a customer.
The hub rotation was grinding, and there's corrosion, so they want me to fix it even if it means replacing parts.
When I received it, the parts around the hub axle were already removed.
↑The cone on the right side
↑The cone on the left side
The left side looked like it might not need replacement.
But in the end, I replaced it anyway.
These are the parts around the hub axle.
It's USB bearing spec, and I'm not sure if the original left and right cage bearings are preserved,
but since the right cone has bitten into the hub axle, it seems definite that the left and right of the cones are original.
Both cones were no good.
This hub is USB bearing spec.
At our shop, we sell parts like cones and cup nuts that normally come as 4-piece sets individually or use them for repairs, but
the list price including tax for ball bearings or a USB bearing kit with 2 cones and 2 cup nuts is ¥13,306.
Based on my assessment, the ceramic bearings don't seem to need replacement, so
I'd like to go with this parts replacement, replacing the left cone which was in better condition as well, but
a complete wheel parts kit with 2 each of cones, cup nuts, cage bearings, and seals is ¥11,694 for ball bearing spec and ¥18,108 for USB spec.
Since it's cheaper to buy a hub kit even if it means wasting ball bearings
rather than buying individual cones and cup nuts,
I decided to first try "steel ball hub kit + reusing ceramic bearings," and if the rotation feels rough
(meaning the ceramic bearing balls were also damaged), I'll swap in the bearing balls from the hub kit
and sell the USB spec version instead.
I extracted the cones from the hub body and cleaned the interior.
After this I pressed in the new cones.
The freewheel body bearings were bad, so I replaced both.
↑The timeline jumps here, but this is the after shot
Looking at the scratches on the hub axle and rust migration, the rear bearing looks worse,
but actually the front bearing was more damaged.
The cage lift spring had no deformation, so I reused it as-is.
↑This is a bearing from before seals were added to the surface facing the freewheel body interior.
The grease inside was also dirty.
I also removed the rear bearing and cleaned it.
Current bearings on complete wheels are installed with a blue seal on the side facing outward from the freewheel body
and a black seal on the side facing inward, so I'm following that standard.
I only reused the ceramic ball cage bearing.
Since the rotation had no grinding, I went ahead with the plan I mentioned earlier to
sell using the ball bearing hub kit,
but to make that determination I needed to fill the bearing area with grease,
and that grease is Kluber (high-cost specialty ceramic bearing grease),
so I was relieved that it didn't go to waste.
The rim was offset to the right.
If it was centered perfectly when hung and then used over the years, it could look like this,
but I didn't check the original hub assembly or see a temporary center reference,
and since I extracted cones from the hub body and pressed in new ones and other variables are at play,
I can't definitively say what caused this result.
There was considerable lateral wobble, and as I trued the wheel focusing heavily on tightening the non-freewheel side nipples,
the center came out naturally by the time I finished truing.
It's fixed.
The hub rotation has no grinding.
There's that new-product "unbroken-in" feel where the bearing balls don't have clean wear marks on the races yet,
but that will only go away with riding time.
↑The removed right cone
I'm returning the original parts to the customer as-is since the hub kit price includes ball bearings.
Since I used new seals, the only new part in the image above is the steel ball cage bearing.
The hub rotation was grinding, and there's corrosion, so they want me to fix it even if it means replacing parts.
When I received it, the parts around the hub axle were already removed.
↑The cone on the right side
↑The cone on the left side
The left side looked like it might not need replacement.
But in the end, I replaced it anyway.
These are the parts around the hub axle.
It's USB bearing spec, and I'm not sure if the original left and right cage bearings are preserved,
but since the right cone has bitten into the hub axle, it seems definite that the left and right of the cones are original.
Both cones were no good.
This hub is USB bearing spec.
At our shop, we sell parts like cones and cup nuts that normally come as 4-piece sets individually or use them for repairs, but
the list price including tax for ball bearings or a USB bearing kit with 2 cones and 2 cup nuts is ¥13,306.
Based on my assessment, the ceramic bearings don't seem to need replacement, so
I'd like to go with this parts replacement, replacing the left cone which was in better condition as well, but
a complete wheel parts kit with 2 each of cones, cup nuts, cage bearings, and seals is ¥11,694 for ball bearing spec and ¥18,108 for USB spec.
Since it's cheaper to buy a hub kit even if it means wasting ball bearings
rather than buying individual cones and cup nuts,
I decided to first try "steel ball hub kit + reusing ceramic bearings," and if the rotation feels rough
(meaning the ceramic bearing balls were also damaged), I'll swap in the bearing balls from the hub kit
and sell the USB spec version instead.
I extracted the cones from the hub body and cleaned the interior.
After this I pressed in the new cones.
The freewheel body bearings were bad, so I replaced both.
↑The timeline jumps here, but this is the after shot
Looking at the scratches on the hub axle and rust migration, the rear bearing looks worse,
but actually the front bearing was more damaged.
The cage lift spring had no deformation, so I reused it as-is.
↑This is a bearing from before seals were added to the surface facing the freewheel body interior.
The grease inside was also dirty.
I also removed the rear bearing and cleaned it.
Current bearings on complete wheels are installed with a blue seal on the side facing outward from the freewheel body
and a black seal on the side facing inward, so I'm following that standard.
I only reused the ceramic ball cage bearing.
Since the rotation had no grinding, I went ahead with the plan I mentioned earlier to
sell using the ball bearing hub kit,
but to make that determination I needed to fill the bearing area with grease,
and that grease is Kluber (high-cost specialty ceramic bearing grease),
so I was relieved that it didn't go to waste.
The rim was offset to the right.
If it was centered perfectly when hung and then used over the years, it could look like this,
but I didn't check the original hub assembly or see a temporary center reference,
and since I extracted cones from the hub body and pressed in new ones and other variables are at play,
I can't definitively say what caused this result.
There was considerable lateral wobble, and as I trued the wheel focusing heavily on tightening the non-freewheel side nipples,
the center came out naturally by the time I finished truing.
It's fixed.
The hub rotation has no grinding.
There's that new-product "unbroken-in" feel where the bearing balls don't have clean wear marks on the races yet,
but that will only go away with riding time.
↑The removed right cone
I'm returning the original parts to the customer as-is since the hub kit price includes ball bearings.
Since I used new seals, the only new part in the image above is the steel ball cage bearing.