Fuel EXe (Light E-MTB)

e-mtb

Origin

Launched July 2022 (for 2023 model year) as Trek's entry into the lightweight/low-power eMTB segment. Trek partnered with German robotics company TQ Systems to develop the HPR50 motor specifically for this application. It was a direct response to the Specialized Levo SL and Orbea Rise.

Specifications

Frame: OCLV Mountain Carbon (9.x) or Alpha Platinum Aluminum (5/8, from 2024). Lightweight e-MTB chassis, internal frame storage.
Weight: kg
Drivetrain: 1×12 — SRAM X0 Eagle AXS T-Type electronic (flagship) to Shimano Deore mechanical (entry).
Brakes: 4-piston hydraulic disc — SRAM Maven Silver 200 mm (flagship) / Shimano MT4100 (entry).
Wheels: 29" (27.5" rear mullet compatible); Bontrager Line Pro 30 OCLV carbon (flagship), tubeless-ready.
Lineup: Light e-MTB / Trail e-MTB (50Nm assist category)

Signature technologies

TQ HPR50 Harmonic Pin Ring motor — gearless concentric design, nearly silent
Total drive system weight only 3.9 kg — among lightest eMTB systems ever produced
Near-zero pedal drag above 25 kph — rides like an analog bike when motor cuts off
Seamless top-tube integrated LED display with Bluetooth and ANT+
Range extender battery (160Wh) fits in water bottle cage

The verdict

+Strengths

Nearly silent motor — TQ HPR50 is among quietest eMTB motors available
Natural ride feel — minimal drag, feels like an analog bike above cutoff
Lightweight for an eMTB — under 19 kg in top spec
Stealth appearance — does not look like a typical e-MTB
Great suspension performance and trail geometry

−Weaknesses

Limited power (50Nm) compared to full-power eMTBs (75-90Nm) — struggles on very steep climbs
Limited battery range (360Wh) — shorter ride time than Bosch 750/800Wh systems
High price for the amount of motor assist provided
Bontrager stock tyres receive criticism (Gen 2/Fuel+ specifically)

Who it’s for

Fit trail rider wanting subtle assist without losing the 'analog bike' feelRider who wants to keep up with e-MTB groups but prefers lightweight handlingPurist who is skeptical of eMTBs — the EXe's stealth and natural ride may convert themRider doing mixed rides — motor-off segments feel natural due to near-zero drag

Buyer’s notes

№ 01

Understand what 50Nm means: this is NOT a full-power eMTB. If you want maximum climbing assist, look at Rail+ or Powerfly+. Fuel EXe is for riders who want subtle, natural assist.

№ 02

The 360Wh battery gives approximately 2-3 hours of moderate trail riding. Budget for the 160Wh range extender (approx €400-500) if you do longer rides.

№ 03

Alloy models (5 and 8) use the same TQ motor system as carbon — the ride quality difference is primarily in weight and component spec, not motor performance.

№ 04

Gen 1 models (2023-2024) being sold at significant discounts as Fuel+ Gen 2 launches. Excellent value if 50Nm/360Wh meets your needs.

№ 05

Check motor area torque specs early — creaking around the crank/motor mount is the most commonly reported issue and is usually a simple fix.

№ 06

Lithuania riders: helmet is now MANDATORY for all e-vehicle users (including pedelecs) since January 1, 2026.

Generations

2023-2024 (carryover into 2025 at reduced prices)
Fuel EXe
- First Trek light eMTB; launched new category
Travel
140mm rear / 150mm front
Frame
Carbon only (2023), Carbon + Aluminum (2024+)
2025/2026
Fuel+
- Renamed Fuel+; adjustable chassis (travel & wheel size), bigger battery, more powerful motor
Travel
Adjustable travel and wheelsize chassis
Frame
Carbon and Aluminum

Law & registration

All three Baltic states follow EU Regulation 168/2013. Pedelec ≤250W continuous with assist up to 25 km/h = bicycle. Above limits = moped/L1e category.