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Thomson Elite X4 stem, 31.8 mm bar / 1-1/8" steerer

Thomson stem. Needs from your bike: Handlebar clamp diameter (fitted bar) and Steerer clamp (stem). Provides: Stem bar-clamp diameter (fitted stem).

The Thomson Elite X4 stem, 31.8 mm bar / 1-1/8" steerer is a stem (component). It requires 2 things of a bike — Handlebar clamp diameter (fitted bar) and Steerer clamp (stem) — read from Thomson. It provides Stem bar-clamp diameter (fitted stem) to the parts that mount on it. On every bike page its verdict is computed from those requirements against the bike's cited facts: when a fact is missing the answer is "unknown", never a guess.

Requires — Handlebar clamp diameter (fitted bar)31.8 mm
Requires — Steerer clamp (stem)1-1/8" (28.6 mm)
Provides — Stem bar-clamp diameter (fitted stem)31.8 mm

Handlebar clamp diameter (fitted bar) and Steerer clamp (stem) are safety-critical: a wrong answer could hurt you, so we say "fits" only when the bike's fact is confirmed by two independent sources. With one source the honest answer is "unknown"; with none it is "unknown — safety-critical".

Does this part fit my bike?
Find your bike under "Fits these bikes" below, or open your bike's "Cockpit" region page. The verdict there is computed from this part's requirements against the bike's cited facts — with its confidence and sources.
What does "does not fit" mean here?
That a fact on file for the bike contradicts a requirement of this part — a confident no, with both values shown.

Standards

  • 31.8 mm
  • 1-1/8" (28.6 mm)

Needs from your bike: Handlebar clamp diameter (fitted bar): 31.8 mm · Steerer clamp (stem): 1-1/8" (28.6 mm)

Provides: Stem bar-clamp diameter (fitted stem): 31.8 mm

Stem

Find this part

Choose the right variant and check the fit for your bike.

Fits these bikes

Brompton C Line 12-speed (2025)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike nothing on file · part 31.8 mm — not on file
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file

Sources:

Canyon Grail CF SL 7 (2025)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike nothing on file · part 31.8 mm — not on file
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file

Sources:

Giant Defy Advanced 2 (2025)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike nothing on file · part 31.8 mm — not on file
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file

Sources:

Giant Escape 3 (2024)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike 25.4 mm (single-source) · part 31.8 mm — mismatch
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file

Sources:

Giant Fathom 29 2 (2022)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike 35 mm (single-source) · part 31.8 mm — mismatch
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file

Sources:

Giant Glory Advanced (2025)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike 35 mm (single-source) · part 31.8 mm — mismatch
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file
Giant Propel Advanced 2 (2027)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike nothing on file · part 31.8 mm — not on file
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file

Sources:

Giant Reign 29 2 (2021)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike 35 mm (single-source) · part 31.8 mm — mismatch
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file

Sources:

Giant Revolt Advanced 2 (2025)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike 31.8 mm (single-source) · part 31.8 mm — match
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file
Giant Roam 2 Disc (2021)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike 31.8 mm (single-source) · part 31.8 mm — match
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file

Sources:

Giant Talon 2 (2025)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike 31.8 mm (single-source) · part 31.8 mm — match
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file

Sources:

Giant Talon E+ (2026)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike 31.8 mm (single-source) · part 31.8 mm — match
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file

Sources:

Giant TCX Advanced Pro 2 (2023)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike nothing on file · part 31.8 mm — not on file
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file

Sources:

Giant Trance X 29 2 (2022)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike 35 mm (single-source) · part 31.8 mm — mismatch
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file
Giant XTC Jr 24 (2015)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike 25.4 mm (single-source) · part 31.8 mm — mismatch
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file

Sources:

Kona Sutra (2025)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike nothing on file · part 31.8 mm — not on file
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file

Sources:

Liv Flourish 2 (2017)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike 25.4 mm (single-source) · part 31.8 mm — mismatch
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file

Sources:

State Bicycle Co. Core-Line (2024)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike nothing on file · part 31.8 mm — not on file
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file

Sources:

Surly Disc Trucker 700c (2024)unknown · confidence: single-source
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike 31.8 mm (single-source) · part 31.8 mm — match
  • Steerer clamp (stem) (safety-critical): bike 1-1/8" (28.6 mm) (single-source) · part 1-1/8" (28.6 mm) — match

Downgraded to "unknown": every fact matches, but a safety-critical one is confirmed by a single source only — we say "fits" on a safety dimension only with two independent sources

Tern GSD S10 (2025)unknown — safety-critical · confidence: single-source We can't answer this yet, and this is one where a guess could hurt you.
Why? The facts we compared (2 dimensions compared)
  • Handlebar clamp diameter (fitted bar) (safety-critical): bike nothing on file · part 31.8 mm — not on file
  • Steerer clamp (stem) (safety-critical): bike nothing on file · part 1-1/8" (28.6 mm) — not on file

Sources:

See all 23 bikes

Sources

The spec sheets we read. Every fact above cites one of them.

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