Bottom steerer bearing help

Discuss light weight issues concerning road bikes & parts.
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by RocketRacing

Hi folks.

As a warning, i am about to brutalize termanology, so bear(no pun intended) with me.

So i have a 2015 felt f2 with a hidden/integrated bearing at the bottom of the tapered steerer (see photo to compensate for incorrect termanology).

I upgraded my top and bottom steerer/headset bearing to cane creek aer. Sadly, my bike is not in their website bearing calculator system.

Looking at felt specs for inner and outer bearing diameter, i ordered what i thought should fit. When i got it, the measurements were correct for inner and outer diameter.

When i installed it on the fork, if appeared fully pressed in, but the fork would not sit flush with the top of the fork. There was a good 0.5-1cm gap.

Feeling a bit silly, i noted that i did not consider bearing depth. The original fsa bearing was the metal bearing only, with not bottom seal. The aer was a metal bearing with an aluminum/rubber seal below... presumably for traditional non hidden interfaces. However, when removing the seal, the aer bearing was shorter than the original.

So now it will fit, but i worry the aer bearing is too short. Or will the tapering of the headtube solve that by compressing it in place?

Thanks for any help

by Weenie

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by wheelsONfire

Hm, perhaps that has to do with the crown race depth?
Shouldn't bearings have a standard, it would seems resonable.

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by mattr

No such thing as a standard in cycling.
Just an ever changing range of designs.

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by RocketRacing

To again butcher termanology, the bearings shared internal and external diameters, and were of different thickness. I removed the race/seal from the aer bearing (fsa did not have that). This made the aer bearing thinner vs the fsa

However, the angles of the circumferential taper were the same, thus the coned part of the fork would seem to fit in a similar fasion.

I am trying to visualize what supports the vertical force of a fork/bearing, and from what i can gather it is the coned part of the bottom of the tapered steerer tube pressing against the bottom hedset bearing. I will see what i can come up with online to make sure i understand. I don’t want to damage my fork.

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by RocketRacing

Here are the headset specs felt provided me. Time to study, as i assumed there was more standardization, and ordered internal and external sizes to match, with no consideration to tapering and thickness.

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