Industry Nine iRiX Headset
What the checker says1958will not fit
Run variant by variant through the mountain 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 6104 verified mountain bike parts in this catalog. 5957 produced no finding of any kind; that is iRiX ZS44/ZS56 (Both/Solid). iRiX EC34/EC44 clears 5866. Each variant produces 178 to 407 distinct errors and 0 distinct warnings.
Will not fit
Headset upper, Frame. 885 more findings from the same check, on up to 2 of the 258 verified frames each.
Headset lower, Frame. 707 more findings from the same check, on up to 2 of the 258 verified frames each.
Headset steerer, Fork. 366 more findings from the same check, on up to 1 of the 490 verified forks each.
Open a variant in the builder to see the ones that apply to your own parts.
$165.00 to $195.00 MSRP·100 to 110 g
What the maker states
- Upper
- Assembly EC34/28.6 (S.H.I.S.) (on 2 of 6 variants); Assembly IS41/28.6 (S.H.I.S.) (on 1 of 6 variants); Assembly IS42/28.6 (S.H.I.S.) (on 1 of 6 variants); Assembly ZS44/28.6 (S.H.I.S.) (on 1 of 6 variants); and 1 further value across 1 of 6 variants
- Lower
- Assembly IS52/40 (S.H.I.S.) (on 2 of 6 variants); Assembly ZS56/40 (S.H.I.S.) (on 2 of 6 variants); Assembly EC44/40 (S.H.I.S.) (on 1 of 6 variants); Assembly EC49/40 (S.H.I.S.) (on 1 of 6 variants)
- Steerer
- Tapered (1.5-1.125)
A value shown as a set or a range differs between this model’s variants and is never one variant’s spec.
6 verified variants
| Variant | Upper | Lower | Price (MSRP) | Weight | Source | Last checked | Build |
|---|---|---|---|---|---|---|---|
| iRiX ZS44/ZS56 (Both/Solid) | assembly ZS44/28.6 (S.H.I.S.) | assembly ZS56/40 (S.H.I.S.) | $195.00 | 110 g | maker’s page | 2026-07-23 | Build with this |
| iRiX IS41/IS52 | assembly IS41/28.6 (S.H.I.S.) | assembly IS52/40 (S.H.I.S.) | $165.00 | 100 g | maker’s page | 2026-08-27 | Build with this |
| iRiX IS42/IS52 | assembly IS42/28.6 (S.H.I.S.) | assembly IS52/40 (S.H.I.S.) | $165.00 | not stated | maker’s page | 2026-09-04 | Build with this |
| iRiX ZS56/ZS56 | assembly ZS56/28.6 (S.H.I.S.) | assembly ZS56/40 (S.H.I.S.) | $195.00 | not stated | maker’s page | 2026-09-04 | Build with this |
| iRiX EC34/EC44 | assembly EC34/28.6 (S.H.I.S.) | assembly EC44/40 (S.H.I.S.) | $195.00 | not stated | maker’s page | 2026-09-04 | Build with this |
| iRiX EC34/EC49 | assembly EC34/28.6 (S.H.I.S.) | assembly EC49/40 (S.H.I.S.) | $195.00 | not stated | maker’s page | 2026-09-04 | Build with this |
Source
Source: each variant links the maker’s own page in the table above. Last checked 2026-07-23 to 2026-09-04.
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.
- 5DEV R-SPEC Trail/Enduro Cranks (Crankset) No conflicts found
- 9point8 Fall Line (Dropper Post) No conflicts found
- 9point8 Stout (31.8, 30mm) (Stem) No conflicts found
- ACID SLX 30 front (Front Wheel) No conflicts found
- ACID SLX 30 rear (Rear Wheel) No conflicts found
- Airdrop Edit MX (Frame) Will not fit
6 of 1881 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.