A Lower/Shorter Crown Race?

Discuss light weight issues concerning road bikes & parts.
Post Reply
User avatar
prendrefeu
Posts: 8591
Joined: Wed Oct 31, 2007 10:32 pm
Location: Los Feliz, Los Angeles, California
Contact:

by prendrefeu

I suppose this question could have easily ended up in any of our subforums (road, cx, mtb) but I'll ask it here:

Has anyone managed to modify a crown race so it places the lower headset bearing closer to the crown on a traditional (non-integrated) fork?
Or does anyone know of a modification that was done in a way to have the same result?

The angled portion of the crown race would stay the same - that's the only part that really engages with the bearing. The portion below the angled bit would be decreased in thickness substantially, thereby brining the bearing much closer to the fork's crown.

Thoughts welcome.
Exp001 || Other projects in the works.

by Weenie


eric
Posts: 2196
Joined: Tue Nov 11, 2003 9:47 pm
Location: Santa Cruz, California, USA
Contact:

by eric

All the crown races I have seen have been very short, with no room to make them shorter. Admittedly it's been a while since I looked at an external headset.
But it seems like it'd be easier to find a shorter one with the appropriate bearing seat dimensions than to get a tall one machined down.

User avatar
prendrefeu
Posts: 8591
Joined: Wed Oct 31, 2007 10:32 pm
Location: Los Feliz, Los Angeles, California
Contact:

by prendrefeu

Thanks, I'll do some searching for matches.

I wasn't thinking about machining per se, but that is an option. I was thinking I can just re-build one with a shorter height and have it printed up. A little costly, but at least it will be pure aluminum (or titanium if I want)
Exp001 || Other projects in the works.

Valbrona
Posts: 1482
Joined: Fri Oct 28, 2011 3:25 am
Location: United Kingdom of Great Britain and Northern Ireland

by Valbrona

To what end? You could cut the fork crown instead, depending on what the crown is like.

em3
Posts: 883
Joined: Tue Dec 23, 2008 2:57 pm
Location: NYC

by em3

prendrefeu wrote:... thereby brining the bearing much closer to the fork's crown.
.



To what end? What is ur objective and why? EM3
______________

User avatar
prendrefeu
Posts: 8591
Joined: Wed Oct 31, 2007 10:32 pm
Location: Los Feliz, Los Angeles, California
Contact:

by prendrefeu

The objective is aesthetics.
Exp001 || Other projects in the works.

eric
Posts: 2196
Joined: Tue Nov 11, 2003 9:47 pm
Location: Santa Cruz, California, USA
Contact:

by eric

A good machinist (not me) could shorten it on a lathe, but might need to make some tooling to hold it first.

thisisatest
Shop Owner
Posts: 1980
Joined: Sat Jun 13, 2009 4:02 am
Location: NoVA/DC

by thisisatest

Traditional fork, is the headset and frame traditional as well? Or is it an IS headset?

User avatar
prendrefeu
Posts: 8591
Joined: Wed Oct 31, 2007 10:32 pm
Location: Los Feliz, Los Angeles, California
Contact:

by prendrefeu

Traditional frame/headtube (external type headset) (aka 'ahead')
Fork designed for internal headset: the diameter of the crown is longer than traditional.

That (the diameter difference) is a separate issue: I may end up having to make my own lower cup to match things aesthetically.
However I've noticed that traditional headset/fork interfaces were designed to be o.k. with the space created by the crown race.
On integrated/internal, it seems that the headtube somewhat masks the space a bit, making it very slim (1mm gap or less between headtube and fork, much more aesthetically pleasing).

:noidea: Maybe I should look into other headsets.
Exp001 || Other projects in the works.

by Weenie


thisisatest
Shop Owner
Posts: 1980
Joined: Sat Jun 13, 2009 4:02 am
Location: NoVA/DC

by thisisatest

If you're using a campy-fit crown on an IS-spec bearing (even if that bearing is in external cups), the for Lo will sit tall. I doubt this is the case but it's worth looking into. If the crown were to, say, be pressed upside-down, it may fit in a lathe that way and have access to the bottom of the race to cut it away. Then all you need is the lathe.

Post Reply
  • Similar Topics
    Replies
    Views
    Last post