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Fox Transfer Factory Dropper Post

What the checker says9will not fit2048worth knowing

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 5824 verified mountain bike parts in this catalog. 5719 produced no finding of any kind; that is Transfer Factory (31.6). Transfer Factory clears 5566. Each variant produces 3 distinct errors and 0 distinct warnings.

Will not fit

  • Will not fiterror · FrameDropper too big: Frame seat tube is 31.6mm but Dropper is 34.9mm - a bigger post cannot fit a smaller tube. On 153 of the 258 verified frames in this catalog. Applies to 5 of 14 variants.
  • Will not fiterror · FrameDropper too small: Frame seat tube is 31.6mm but Dropper is 30.9mm. A shim or adapter may make other sizes or standards work, but that is a modification, not a fit. On 153 of the 258 verified frames in this catalog. Applies to 4 of 14 variants.
  • Will not fiterror · FrameDropper too big: Frame seat tube is 30.9mm but Dropper is 31.6mm - a bigger post cannot fit a smaller tube. On 58 of the 258 verified frames in this catalog. Applies to 5 of 14 variants.
  • Will not fiterror · FrameDropper too big: Frame seat tube is 30.9mm but Dropper is 34.9mm - a bigger post cannot fit a smaller tube. On 58 of the 258 verified frames in this catalog. Applies to 5 of 14 variants.
  • Will not fiterror · FrameDropper too small: Frame seat tube is 34.9mm but Dropper is 31.6mm. A shim or adapter may make other sizes or standards work, but that is a modification, not a fit. On 41 of the 258 verified frames in this catalog. Applies to 5 of 14 variants.
  • Will not fiterror · FrameDropper too small: Frame seat tube is 34.9mm but Dropper is 30.9mm. A shim or adapter may make other sizes or standards work, but that is a modification, not a fit. On 41 of the 258 verified frames in this catalog. Applies to 4 of 14 variants.

Dropper diameter, Frame. 3 more findings from the same check, on up to 6 of the 258 verified frames each.

Open a variant in the builder to see the ones that apply to your own parts.

Worth knowing

    Dropper insertion, Frame. 2048 more findings from the same check, on up to 2 of the 258 verified frames each.

    Open a variant in the builder to see the ones that apply to your own parts.

    The checker compares the dimensions listed in what we check, and what we don’t. “No conflicts found” means no conflict among those dimensions — not a guarantee that a build works. Errors mean it won’t fit; warnings mean it works but check; infos are notes.

    $329.00 MSRP·520 to 705 g

    What the maker states

    Diameter
    31.6 mm diameter (on 5 of 14 variants); 34.9 mm diameter (on 5 of 14 variants); 30.9 mm diameter (on 4 of 14 variants)
    Drop
    Ranges from 120 mm of drop to 240 mm of drop (5 distinct values, across 14 of 14 variants)

    A value shown as a set or a range differs between this model’s variants and is never one variant’s spec.

    14 verified variants

    VariantDiameterDropPrice (MSRP)WeightSourceLast checkedBuild
    Transfer Factory31.6 mm diameter180 mm of drop$329.00608 gmaker’s page2026-07-16Build with this
    Transfer Factory (34.9)34.9 mm diameter180 mm of drop$329.00625 gmaker’s page2026-07-16Build with this
    Transfer Factory (30.9)30.9 mm diameter180 mm of drop$329.00600 gmaker’s page2026-07-16Build with this
    Transfer Factory (30.9)30.9 mm diameter120 mm of drop$329.00520 gmaker’s page2026-07-16Build with this
    Transfer Factory (30.9)30.9 mm diameter150 mm of drop$329.00560 gmaker’s page2026-07-16Build with this
    Transfer Factory (30.9)30.9 mm diameter210 mm of drop$329.00640 gmaker’s page2026-07-16Build with this
    Transfer Factory (31.6)31.6 mm diameter120 mm of drop$329.00528 gmaker’s page2026-07-16Build with this
    Transfer Factory (31.6)31.6 mm diameter150 mm of drop$329.00568 gmaker’s page2026-07-16Build with this
    Transfer Factory (31.6)31.6 mm diameter210 mm of drop$329.00648 gmaker’s page2026-07-16Build with this
    Transfer Factory (31.6)31.6 mm diameter240 mm of drop$329.00688 gmaker’s page2026-07-16Build with this
    Transfer Factory (34.9)34.9 mm diameter120 mm of drop$329.00545 gmaker’s page2026-07-16Build with this
    Transfer Factory (34.9)34.9 mm diameter150 mm of drop$329.00585 gmaker’s page2026-07-16Build with this
    Transfer Factory (34.9)34.9 mm diameter210 mm of drop$329.00665 gmaker’s page2026-07-16Build with this
    Transfer Factory (34.9)34.9 mm diameter240 mm of drop$329.00705 gmaker’s page2026-07-16Build with this
    The rest of what the maker states1 not published

    1 further field the checker looks for is not published by Fox, so we leave it blank rather than estimate it, and that check stays silent on this dropper post. It is cable pull. Each is recorded as “not stated by the maker (not checked)”.

    Source: each variant links the maker’s own page in the table above. Last checked 2026-07-16.

    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.

    6 of 1858 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.

    Where this sits

    Fox Transfer Factory is the first model on that list.Next: Fox Transfer NeoAll Fox dropper postsOpen a variant in the builder to see the ones that apply to your own parts