Ritchey External Cup EC Threadless Headset Headset
What the checker says14will not fit
Run variant by variant through the road bike builder’s own engine. Every sentence below is the checker’s, unedited. Nothing here says this part fits your bike; it says what it does and does not fit among the parts we hold.
Checked against 1030 verified road bike parts in this catalog. 1016 produced no finding of any kind.
Will not fit
Rg headset steerer, Fork. 14 more findings from the same check, on up to 1 of the 17 verified forks each.
Open a variant in the builder to see the ones that apply to your own parts.
$22.95 MSRP·156 g
What the maker states
- Upper
- Assembly EC34/28.6 (S.H.I.S.)
- Lower
- Assembly EC34/30 (S.H.I.S.)
- Steerer
- Straight-1-1-8
Source
Source: the maker’s page. Last checked 2026-08-25.
Checked against
The checker ran this model against every verified part below that it has a slot for, the same way it checks a build in the builder. What follows is the verdict it actually produced for that specific pairing — not a recommendation, and not a guarantee any of these parts fits your own bike.
- 3T Aeroflux Integrale (Handlebar) No conflicts found
- 3T Apto Stealth Stem (Stem) No conflicts found
- 3T Superergo LTD (standard, non-INTEGRALE) (Handlebar) No conflicts found
- All-City Zig Zag Frameset (Frame) No conflicts found
- Argon 18 SUM D-Shape Seatpost (Seatpost) No conflicts found
- Argon 18 Sum Frameset (Frame) No conflicts found
6 of 702 counterparts with a page of their own that the checker actually probed this model against, in alphabetical order by brand and model — never by price, popularity or the verdict itself.