Configuration checked October 11, 2026: U.S. FX+1 Stepover, Medium, Dark Star, model 5335258. FX+1S and Midstep are separate configurations. Model year stays unavailable: a 2025 service-manual cover and a 2026 file-update name do not establish this retail bicycle’s year.
Why does this record use 520 Wh rather than 540 Wh?
The selected model’s technical Specs pane states 520 Wh. Its linked service manual identifies battery BP-TR23A, part 5329958; the linked Hyena Throttle owner manual, English page 8, lists that battery’s energy as 520 Wh. These specific technical sources corroborate the selected listing.
The general FX+ family editorial page states 540 Wh in its throttle-family section. We retain that competing statement and prefer the model/component-specific evidence; we do not invent a generation change, manufacturer correction or new battery option to explain the difference.
What do the selected specifications actually establish?
| Field | Claim or observation | Scope and limit |
|---|---|---|
| Battery | 520 Wh; BP-TR23A | Selected Specs and linked component manuals; no measured capacity |
| Nominal battery voltage | 48 VDC | Owner manual explicitly labels nominal; Service parts list’s 47.3 V is unclassified |
| Motor | Rear hub; 500 W rated; maximum torque claim 60 Nm | MRC-TR24A owner manual; no peak-power or measured wheel-output claim |
| Assistance | Class 2; 20 mph cap | Selected FX+1 specification, not FX+1S settings or permission on every route |
| Maximum range | Up to 50 miles, maker claim | No tested range, route assumptions or personal guarantee supplied here |
| Wheels and tyres | 27.5-inch geometry; 650 × 50 mm tyre listing | Wheel-inch value is explicitly in geometry, not inferred from tyre notation |
| Listed Medium weight | 22.10 kg / 48.73 lb | Maker’s pre-production-weight caveat; battery/pedal inclusion and final equipment not established |
| Total limit | 300 lb / 136 kg listed gross limit | Includes bicycle, rider and cargo; not a rider-plus-cargo scalar |
For the manuals, open the selected manufacturer page, choose Service, then the FX+1 throttle service manual or Hyena Throttle owner manual. Document titles and the matching BP-TR23A component are part of our provenance. The public record links to the maker’s document index, not copied access parameters or an uploaded private source bundle.
Why aren’t 47.3 V, 48 V and 54.9 V interchangeable?
The selected Service parts entry describes a 520 Wh, 47.3 V integrated battery without classifying that voltage. The matching BP-TR23A owner manual explicitly gives 48 VDC nominal, which is the nominal value retained in this record. The selected charger listing’s 54.9 V output is a different specification, not a replacement battery-voltage label.
The manual also lists 10.66 Ah and 520 Wh. Those manufacturer labels are not an exact measured multiplication at every operating voltage. Do not substitute a battery or charger because one nominal number looks similar. Compatibility, service and installation must follow the exact equipment instructions.
What does the Medium fit guidance mean?
| Measurement | Maker Medium guidance | What to check |
|---|---|---|
| Rider height | 165–175 cm | Starting guidance; check reach and comfortable controls on the actual bike |
| Inseam | 77–83 cm | Use the maker’s measurement method and test the actual configuration |
| Standover | 78.0 cm geometry value | Geometry and inseam numbers are not an automatic clearance guarantee |
Other frame sizes have different guidance and component dimensions. This record does not pool Small, Large or XL measurements into the Medium. Use a test fit and the applicable sizing guidance rather than treating a height boundary as a guaranteed match.
Is 300 lb a rider-and-cargo allowance?
No. Trek defines the limit as bicycle, rider and cargo together. The bicycle and added equipment consume part of that budget. Its Medium listing weight is not our measurement and has a pre-production caveat; the listing does not expressly settle battery or pedal inclusion. We therefore do not calculate a supposedly exact remaining rider allowance from it.
Racks, child seats, tyres, carriers and vehicle equipment can have separate limits and compatibility requirements. A frame’s gross limit cannot approve a passenger setup or a transport carrier. Use the load-limit guide and weigh the actual complete bicycle before using the rack finder.
What must be checked about the rear-bolt recall?
CPSC recall 26-220, dated January 29, 2026, identifies specified 2026 Trek FX+1/FX+1S Stepover/Midstep and Electra Townie Go models sold before October 28, 2025. Trek also links the consumer recall notice from this selected model’s Service pane. The notice describes a free dealer remedy for affected rear-wheel bolts.
For an affected bicycle, stop riding and follow the maker’s remedy. If applicability or completed repair is uncertain, contact an authorized dealer before riding. A current listing, model number, new purchase or this verified specification record is not an individual safety clearance. We do not provide bolt-replacement instructions or infer repair from a photograph.
Dated evidence and boundaries
Checked October 11, 2026. This is a manufacturer-source configuration record, not a hands-on review. Peak power, measured range, routine user-removability and retail model year remain unavailable. The built-in battery’s replacement installation is referred to a dealer in the owner manual; service access does not imply ordinary user removal.
- Trek selected model 5335258: Specs, Sizing and Service.
- Linked FX+1 service and Hyena Throttle owner manuals — battery BP-TR23A and motor MRC-TR24A; owner English pages 6 and 8.
- CPSC rear-wheel-bolt recall 26-220.
- Trek/Hyena consumer recall notice.
Frequently asked questions
Why is the battery recorded as 520 Wh?
The exact Specs pane and matching BP-TR23A owner manual agree on 520 Wh. We prefer this model-specific technical evidence over the general family editorial 540 Wh statement and retain the conflict record.
Is this a 300 lb rider-and-cargo allowance?
No. Trek defines a gross limit including the bicycle, rider and cargo together. Separate component limits still apply; no exact remaining rider allowance is inferred from the pre-production listing weight.
Can I remove the battery like a detachable commuter pack?
Routine user-removability is unavailable in this record. The manual describes a built-in pack and refers replacement installation to a dealer; service access is not an ordinary user-removal instruction.
Does a new listing mean the rear-bolt recall is resolved?
No. Check the particular bicycle against the maker’s notice and dealer remedy. Stop affected use; if applicability or repair is uncertain, seek an authorized dealer’s inspection before riding.