I ended up in a situation in which my new fork with an integrated crown race imposes lower headset bearing (1.5" 45deg) stack restriction, i.e. I need an additional 1.5mm of bearing height so the fork doesn't rub lower headset cup (bonded to CF tube, by the way).
I see two ways to alleviate the issue:
- Grind a bit of headset lower cup so the fork clears. It's aluminium and hanging part that rubs the fork serves no structural purpose, at least that's what I think.
- Use a shim between lower cup and a bearing. See the CAD drawing for details. I reckon the support of cup from top (45deg surface) and outside (54mm inner diameter) should be enough, after all it's the same mechanism that keeps the bearing in place. But to my surprise, I failed to find such a product!
So, the question(s): is the shim approach a viable solution? If no, why exactly? If yes, can I buy one?
Update: in perfect scenario, I want to use the shim with another, less tall but lighter bearing I already own. I do not want to purchase a taller bearing.