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Discussion Starter · #1 ·
So I'm installing a C record bottom bracket on my bike. The adjusting cup has 9 mm of exposed threads with everything snug so the non drive side sticks out 9mm more than the drive side. Does this make sense?

Thanks
 

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Since you can't have any threads sticking out on the drive side I guess it is what it is as long as the bearings are adjusted properly.
 

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Discussion Starter · #4 ·
After thinking about it maybe it does make sense. The chainring side of the crank must be thicker so the arm is a certain distance from center. The 9 mm evens it out. We'll see once I get the crank.
 

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Why wouldn't you just use a cartridge? Sure wouldn't want to deal with at fixed cup, if I didn't have to.
 

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So I'm installing a C record bottom bracket on my bike. The adjusting cup has 9 mm of exposed threads with everything snug so the non drive side sticks out 9mm more than the drive side. Does this make sense?
is the spindle asymmetrical? ensure you have the spindle installed properly.

the adjustable cups on my record bb's show more like 5mm of exposed threads for the lockring to secure to. will you use a lockring as well?

Why wouldn't you just use a cartridge?
because cup and cone bb's work great, especially campy ones​.
 

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Discussion Starter · #8 ·
Yes my spindle length is 111 mm, 70 SP. Everything appears correct as sizing goes so it must be to make up for th crank. As I say. I'll have to wait until I get a crank and fit it and see.
 

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Discussion Starter · #10 ·
Here's what it looks like. I'm going to take it apart tomorrow and really look at it.
Blue Green Bicycle wheel rim Bicycle accessory Bicycle part
I'll take a bunch of measurements.
 

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Something isn't right based on that photo. Normally, the lock ring ends up pretty close to the outer face of the NDS cup. It looks like the BB is too long for the BB. It will certainly work, but your feet won't be centered over the frame. What is the width of the BB shell?
 

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Something isn't right based on that photo. Normally, the lock ring ends up pretty close to the outer face of the NDS cup. It looks like the BB is too long for the BB. It will certainly work, but your feet won't be centered over the frame. What is the width of the BB shell?
Wrong. The width of the bearing surfaces on all sizes of axles will be the same, because all bottom bracket shells are the same width...Italian is @ 70.0mm, BSA is 68.0mm. Since this frame is Italian thread it should have the widest bearing seat dimension. A 107, 111, 113...whatever...they'll all have the same dimension for the part of the axle that's actually inside the frame. Only the outer part w/ the flats is longer. It does look like something is messed up here, but I'd have to see the frame & bottom bracket to figure it out.

ETA:

As overall length 'D' changes it's because 'A' & 'C' get longer, 'B' always remains the same.

Text White Line Rectangle Parallel
 

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Discussion Starter · #15 ·
Yes the RD cable passes through the chain stay.
I'm beginning to question the bearings. I'm going out right now to take some measurements.
 

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Are the bearings in cages? Do you possibly have the cages in reversed?
this. Maybe chase the threads too. The cup should be further in.

There is no other lockring. WYSIWYG.
 

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Discussion Starter · #19 ·
The bearings were installed correctly. It really looks like the bearings are the wrong size for this application. They are larger, thus not allowing everything to seat correctly causing the offset.
 

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The bearings were installed correctly. It really looks like the bearings are the wrong size for this application. They are larger, thus not allowing everything to seat correctly causing the offset.
Larger? Campy BB bearings are 1/4". How big are your bearings such that you have displaced the adjustable cup by that much?

The crank axle should be marked as follows: 70-SS-120 with a total length of 113 mm. There exists a 74-SS-120 axle with a total length of 117 mm. It seems most likely that you got one of the axles for a 74mm BB.
 
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