A customer brought me a Racing Zero for service.
It's a limited edition model with CULT (Ceramic Ultra Low Torque) bearings.
Now that I think about it, I wrote earlier that:
・Only Campagnolo makes the new small-diameter CULT bearing spec
・You can't use Campagnolo spare parts on Fulcrum wheels (or vice versa)
So the front wheel of a CULT-spec Racing Zero Night was technically a spec that didn't officially exist. But some of the new Fulcrum models coming out soon will be adopting small-diameter CULT bearings, so this restriction has been lifted.
This front wheel uses CULT bearings from before the small-diameter conversion, and it was designed this way from the start as a limited specification.
It's been used for about three years with no maintenance, so the customer wants a complete overhaul. When I gave the hub a quick feel, the front spins smoothly with no play, but the rear has no play yet there's a strange grinding sensation. I thought it might be pitting, but that wasn't it.
Let me run a quick test while I'm at it. The front hub has no play, so it's perfect for this. Also, there's barely any lateral runout. When I hold the center gauge on the right side, there's a gap between the gauge and the left end nut. The wheel center is slightly off. The rim is shifted toward the left side.
There didn't seem to be any real problems, but since the customer wanted an overhaul, I disassembled it.
After cleaning and reassembling, the direction of the center offset didn't change but the amount increased slightly. This happens because the wheel center shifts depending on how much the wedge-type split centering washer bites in. If I had done a center adjustment before disassembling the hub, it would have been double work.
Now for the rear wheel.
The CULT one-piece driver came out of the hub body. The part press-fitted into the hub body is carbon, but it had been slightly worn and spinning freely. I could push it all the way in and pull it back out by hand without using a press tool.
There were also signs of spinning between the axle and the cone. This is a separate piece to allow replacement, but originally the cone is part of the axle, so it shouldn't be spinning relative to it.
In the case of CULT, there's no membrane-coated ring press-fitted inside the driver. That's because CULT bearings don't use grease. However, to prevent the press-fit depth from changing depending on whether the membrane ring is present or not, a membrane-free ring is installed. It's like the frame of a goldfish scooping net (poい) with all the paper torn away.
The looseness of the driver press-fit was only on the freewheel side. I set it with anaerobic adhesive and a press tool, and now it won't budge, so there's no problem. I let it dry overnight, which took up a lot of work time. My apologies (← that's my excuse).
The freewheel pawl spring had no deformation at all, so I didn't replace it.
It's a limited edition model with CULT (Ceramic Ultra Low Torque) bearings.
Now that I think about it, I wrote earlier that:
・Only Campagnolo makes the new small-diameter CULT bearing spec
・You can't use Campagnolo spare parts on Fulcrum wheels (or vice versa)
So the front wheel of a CULT-spec Racing Zero Night was technically a spec that didn't officially exist. But some of the new Fulcrum models coming out soon will be adopting small-diameter CULT bearings, so this restriction has been lifted.
This front wheel uses CULT bearings from before the small-diameter conversion, and it was designed this way from the start as a limited specification.
It's been used for about three years with no maintenance, so the customer wants a complete overhaul. When I gave the hub a quick feel, the front spins smoothly with no play, but the rear has no play yet there's a strange grinding sensation. I thought it might be pitting, but that wasn't it.
Let me run a quick test while I'm at it. The front hub has no play, so it's perfect for this. Also, there's barely any lateral runout. When I hold the center gauge on the right side, there's a gap between the gauge and the left end nut. The wheel center is slightly off. The rim is shifted toward the left side.
There didn't seem to be any real problems, but since the customer wanted an overhaul, I disassembled it.
After cleaning and reassembling, the direction of the center offset didn't change but the amount increased slightly. This happens because the wheel center shifts depending on how much the wedge-type split centering washer bites in. If I had done a center adjustment before disassembling the hub, it would have been double work.
Now for the rear wheel.
The CULT one-piece driver came out of the hub body. The part press-fitted into the hub body is carbon, but it had been slightly worn and spinning freely. I could push it all the way in and pull it back out by hand without using a press tool.
There were also signs of spinning between the axle and the cone. This is a separate piece to allow replacement, but originally the cone is part of the axle, so it shouldn't be spinning relative to it.
In the case of CULT, there's no membrane-coated ring press-fitted inside the driver. That's because CULT bearings don't use grease. However, to prevent the press-fit depth from changing depending on whether the membrane ring is present or not, a membrane-free ring is installed. It's like the frame of a goldfish scooping net (poい) with all the paper torn away.
The looseness of the driver press-fit was only on the freewheel side. I set it with anaerobic adhesive and a press tool, and now it won't budge, so there's no problem. I let it dry overnight, which took up a lot of work time. My apologies (← that's my excuse).
The freewheel pawl spring had no deformation at all, so I didn't replace it.