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PRO Tharsis Dropper Post

What the checker says12will 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 Tharsis 160 (31.6). Tharsis 200 (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 2 of 7 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 7 variants.
  • Will not fiterror · FrameDropper too small: Frame seat tube is 31.6mm but Dropper is 27.2mm. 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 1 of 7 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 2 of 7 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 7 variants.
  • Will not fiterror · FrameDropper too small: Frame seat tube is 30.9mm but Dropper is 27.2mm. A shim or adapter may make other sizes or standards work, but that is a modification, not a fit. On 58 of the 258 verified frames in this catalog. Applies to 1 of 7 variants.

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

Dropper diameter small, Frame. 3 more findings from the same check, on up to 41 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 PRO Tharsis 200 (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 7 variants.
  • Worth knowinginfo · FrameLong-drop post: the PRO Tharsis 200 (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 7 variants.
  • Worth knowinginfo · FrameLong-drop post: the PRO Tharsis 200 (31.6) (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 7 variants.
  • Worth knowinginfo · FrameLong-drop post: the PRO Tharsis 200 (31.6) (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 7 variants.
  • Worth knowinginfo · FrameLong-drop post: the PRO Tharsis 200 (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 7 variants.
  • Worth knowinginfo · FrameLong-drop post: the PRO Tharsis 200 (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 7 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.

$240.00 to $280.00 MSRP·417 to 545 g

What the maker states

Diameter
30.9 mm diameter (on 2 of 7 variants); 31.6 mm diameter (on 2 of 7 variants); 34.9 mm diameter (on 2 of 7 variants); 27.2 mm diameter (on 1 of 7 variants)
Drop
160 mm of drop (on 3 of 7 variants); 200 mm of drop (on 3 of 7 variants); 100 mm of drop (on 1 of 7 variants)

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

7 verified variants

VariantDiameterDropPrice (MSRP)WeightSourceLast checkedBuild
Tharsis 10027.2 mm diameter100 mm of drop$240.00417 gmaker’s page2026-09-08Build with this
Tharsis 160 (30.9)30.9 mm diameter160 mm of drop$260.00485 gmaker’s page2026-09-08Build with this
Tharsis 160 (31.6)31.6 mm diameter160 mm of drop$260.00485 gmaker’s page2026-09-08Build with this
Tharsis 160 (34.9)34.9 mm diameter160 mm of drop$260.00485 gmaker’s page2026-09-08Build with this
Tharsis 200 (30.9)30.9 mm diameter200 mm of drop$280.00545 gmaker’s page2026-09-08Build with this
Tharsis 200 (31.6)31.6 mm diameter200 mm of drop$280.00545 gmaker’s page2026-09-08Build with this
Tharsis 200 (34.9)34.9 mm diameter200 mm of drop$280.00545 gmaker’s page2026-09-08Build with this
The rest of what the maker states1 not published

1 further field the checker looks for is not published by PRO, 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 2026-09-08.

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

Previous: PRO LT 150PRO Tharsis is the last model on that list.All PRO dropper postsOpen a variant in the builder to see the ones that apply to your own parts