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9point8 Fall Line Dropper Post

What the checker says9will not fit768worth 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 Fall Line R. Fall Line (30.9) clears 5566. Each variant produces 3 distinct errors and 0 distinct warnings.

Will not fit

  • 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 6 of 14 variants.
  • 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 2 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 6 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 2 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 6 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 6 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

  • Worth knowinginfo · FrameLong-drop post: the 9point8 Fall Line (200mm) needs deep seat-tube insertion - check the maker's insertion calculator for your Antidote Carbonjack frame size. On 2 of the 258 verified frames in this catalog. Applies to 1 of 14 variants.
  • Worth knowinginfo · FrameLong-drop post: the 9point8 Fall Line (200mm) needs deep seat-tube insertion - check the maker's insertion calculator for your Transition Spur Carbon frame size. On 2 of the 258 verified frames in this catalog. Applies to 1 of 14 variants.
  • Worth knowinginfo · FrameLong-drop post: the 9point8 Fall Line (30.9) (200mm) needs deep seat-tube insertion - check the maker's insertion calculator for your Antidote Carbonjack frame size. On 2 of the 258 verified frames in this catalog. Applies to 1 of 14 variants.
  • Worth knowinginfo · FrameLong-drop post: the 9point8 Fall Line (30.9) (200mm) needs deep seat-tube insertion - check the maker's insertion calculator for your Transition Spur Carbon frame size. On 2 of the 258 verified frames in this catalog. Applies to 1 of 14 variants.
  • Worth knowinginfo · FrameLong-drop post: the 9point8 Fall Line (34.9) (200mm) needs deep seat-tube insertion - check the maker's insertion calculator for your Antidote Carbonjack frame size. On 2 of the 258 verified frames in this catalog. Applies to 1 of 14 variants.
  • Worth knowinginfo · FrameLong-drop post: the 9point8 Fall Line (34.9) (200mm) needs deep seat-tube insertion - check the maker's insertion calculator for your Transition Spur Carbon frame size. On 2 of the 258 verified frames in this catalog. Applies to 1 of 14 variants.

Dropper insertion, Frame. 762 more findings from the same check, on up to 1 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.

$270.00 to $349.00 MSRP·384 to 732 g

What the maker states

Diameter
30.9 mm diameter (on 6 of 14 variants); 31.6 mm diameter (on 6 of 14 variants); 34.9 mm diameter (on 2 of 14 variants)
Drop
Ranges from 75 mm of drop to 200 mm of drop (6 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
Fall Line31.6 mm diameter175 mm of drop$270.00659 gmaker’s page2026-07-16Build with this
Fall Line R (30.9)30.9 mm diameter150 mm of drop$349.00476 gmaker’s page2026-07-16Build with this
Fall Line R (30.9)30.9 mm diameter75 mm of drop$349.00384 gmaker’s page2026-07-16Build with this
Fall Line R (30.9)30.9 mm diameter100 mm of drop$349.00402 gmaker’s page2026-07-16Build with this
Fall Line R (30.9)30.9 mm diameter125 mm of drop$349.00438 gmaker’s page2026-07-16Build with this
Fall Line R31.6 mm diameter75 mm of drop$349.00398 gmaker’s page2026-07-16Build with this
Fall Line R31.6 mm diameter100 mm of drop$349.00416 gmaker’s page2026-07-16Build with this
Fall Line R31.6 mm diameter125 mm of drop$349.00458 gmaker’s page2026-07-16Build with this
Fall Line R31.6 mm diameter150 mm of drop$349.00498 gmaker’s page2026-07-16Build with this
Fall Line (30.9)30.9 mm diameter175 mm of drop$270.00630 gmaker’s page2026-07-16Build with this
Fall Line (30.9)30.9 mm diameter200 mm of drop$270.00676 gmaker’s page2026-07-16Build with this
Fall Line31.6 mm diameter200 mm of drop$270.00704 gmaker’s page2026-07-16Build with this
Fall Line (34.9)34.9 mm diameter175 mm of drop$290.00683 gmaker’s page2026-07-16Build with this
Fall Line (34.9)34.9 mm diameter200 mm of drop$290.00732 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 9point8, 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

All 9point8 dropper postsOpen a variant in the builder to see the ones that apply to your own parts