The Tern GSD S10 (2025) is a cargo e-bike — representative silhouette: Cargo longtail. We have read 1 specification sheet (Tern Bicycles) and recorded 16 fit facts from it. 10 of the 16 measurements a cargo e-bike needs to answer fit questions are on file; 0 are confirmed by two independent sources. Where a measurement is missing, we say so below — we do not guess.
| Bottom bracket shell | Mid-drive motor (no conventional shell) |
|---|---|
| Front derailleur mount | No front derailleur mount (1x only) |
| Rear axle spacing | Thru-axle, 148 × 12 mm (Boost) |
| Rear thru-axle thread | M12 × 1.0 |
| Seatpost diameter | 34.9 mm |
| Seatpost shape | Round |
| Wheel size (ISO bead seat) | 20" / BMX (ISO 406) |
| Steerer tube | Tapered 1-1/8" to 1-1/2" |
| Front axle spacing | Thru-axle, 110 × 15 mm (Boost) |
| Brake actuation | Hydraulic disc |
| Brake pad shape (fitted calipers) | Magura MT 4-piston (MT5 / MT7 / MT Trail front) |
| Freehub body | Shimano HG, 8/9/10-speed body (also 11/12-speed MTB HG cassettes) |
| Rear speeds | 10 speeds |
| Shift actuation | Mechanical (cable) |
| Chain standard | 10-speed (6.0 mm) |
| Rim internal width | 36 mm |
Confidence: every fact above comes from a single cited source — "derived" on our lattice; none is verified by a second independent publisher yet. A verdict that rests on a safety-critical fact therefore stops at "unknown" rather than "fits".
Not on file (required for a cargo e-bike): Derailleur hanger · Maximum tyre width (frame) · Brake mount, front · Brake mount, rear · Rotor interface (hubs) · Pedal thread. The sheet we read does not state them; until a source does, every fit question that needs one of these reads "unknown" — or "unknown — safety-critical" where a guess could hurt you.
- Why do so many verdicts on this bike read "unknown"?
- Because a verdict needs the bike's measurement for every dimension a part requires, and 6 of the 16 required measurements are not on file. "Unknown" means we could not check — not that it fits, and not that it does not.
- Will the verdicts change?
- Yes. When a second independent source confirms a measurement — or a first one states a missing one — the verdicts are recomputed from the new facts. Nothing on this page is typed by hand.