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Description
Trek's Powerfly FS 4 Gen 3 is a full-suspension electric mountain bike that's highly capable on the trails. The durable aluminium frame and SR Suntour fork incorporate plush suspension, providing 100/120mm of bump-absorbing travel up front and 100mm to the back. With a Bosch electric drive system, you can make the most of the descents, with pedalling assistance up to 15.5mph/25kph helping you back up to the top of the trails each time. The battery and motor are neatly integrated into the frame, while the Bluetooth LED remote and Kiox display can be paired with the eBike Flow app, for activity tracking, navigation and customisation.
A Shimano Deore 10-speed drivetrain and Tektro hydraulic brakes with big rotors bring smooth shifting and powerful braking in all conditions. The wheels are specific to the frame size; 27.5" on the smaller sizes and 29" on the bigger bikes, creating a similar ride feel across the range. A 100mm travel dropper post allows you to move the saddle out of the way as and when required, for more control on steep drops and descents.
Browse our range of Trek electric mountain bikes today.
Frame | Trek Alpha Platinum Aluminium, Removable Integrated Battery (RIB), tapered head tube, internal routing, Motor Armour, rocker link, rack and mudguard mount, ABP, Boost148, 100mm travel |
Fork | SR Suntour XCR 34, air spring, LO R damper, hydraulic lockout, tapered steerer, 44mm offset, oversized crown for eMTB, Boost110, 15mm bolt-on thru-axle, 100mm travel (XS,S) / 120mm travel (S-XL) |
Shock | SR Suntour Edge R, 190mm x 45 mm |
Stem | Bontrager Comp, 31.8mm, Blendr compatible, 7-degree, 60mm length (XS,S) / 70mm length (M-XL) |
Handlebar | Bontrager alloy, 31.8mm, 15mm rise, 720mm width |
Grips | Bontrager XR Trail Comp, nylon lock-on |
Front Brake | Tektro HD-M275 hydraulic disc / Tektro, 6-bolt, 203mm rotor |
Rear Brake | Tektro HD-M275 hydraulic disc / Tektro, 6-bolt, 203mm rotor |
Brake Levers | Tektro |
Rear Derailleur | Shimano Deore M5120, long cage, 10-speed |
Shift Levers | Shimano Deore M4100, 10-speed |
Chain | KMC X10, 10-speed |
Cassette | Shimano Deore M4100, 11-46, 10-speed |
Crankset | FSA Bosch CK-220, 36T ring, 165mm length |
Front Wheel | Rim - Alex MD35, tubeless compatible, 32-hole, 35mm width, Presta valve / hub - Bontrager sealed bearing, alloy axle, 6-bolt, Boost110, 15mm thru-axle |
Rear Wheel | Rim - Alex MD35, tubeless compatible, 32-hole, 35mm width, Presta valve / hub - Bontrager alloy, sealed bearing, alloy axle, 6-bolt, Shimano 8/9/10 freehub, Boost148, 12mm thru-axle |
Front Tyre | Bontrager XR3 Comp, wire bead, 30 tpi, 27.5x2.35" (XS,S), 29x2.30" (M-XL), clincher |
Rear Tyre | Bontrager XR3 Comp, wire bead, 30 tpi, 27.5x2.35" (XS,S), 29x2.30" (M-XL), clincher |
Seatpost | TranzX JD-YSP18, 100mm travel, internal routing, 31.6mm, 361mm length (XS-M) / 425mm length (L-XL) |
Pedals | Available to be purchased separately |
Motor | Bosch Performance Line CX, smart system, magnesium motor body, 85Nm, 250w |
Remote | Bosch LED Remote, smart system |
Display | Bosch Kiox 300, smart system |
Battery | Bosch PowerTube 625Wh, smart system |
Charger | Bosch standard 2A, 230V, smart system |
Electric Assisted Speed Limit | 15.5mph / 25km/h |
Maximum Weight | 136kg / 300lb (combined weight of bicycle, rider and cargo) |
Manufacturer Claimed Weight | 21.65kg / 47.74lbs (excluding battery) (size medium) |
All our bikes are fully built, checked, tuned and tested by our Cytech qualified mechanics and then securely packaged, ready for delivery. All you have to do is add the pedals (if included), attach the handlebars to the stem and tighten them following the included detailed instructions or by watching our video and using the provided FREE tools. Visit our Bike Assembly page to see how you assemble your new bike once you receive it.
All bikes collected from our shop, are built, tested and ready to ride. For hassle-free home delivery and bike set-up from a qualified mechanic use our Premier Delivery Service.
Please note, occasionally, manufacturers may change the specification without notice. Bicycles do not come with pedals unless otherwise specified. Bikes ordered for delivery will not arrive with the pedals installed, please refer to the owners manual and pedal installation guides provided for guidance. We do not install accessories to bikes, including mudguards. Bikes ordered for delivery that have tubeless compatible tyres and rims will arrive with inner tubes installed or with tubeless valves installed, this will be brand dependent. Sealant is available to be purchased separately.
If you require any assistance please contact our Customer Care team.
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Important Update for Our US Customers
We regret to inform you that due to ongoing challenges related to current US tariffs, shopping on Sigma Sports is temporarily unavailable for customers based in the United States.
We understand how disappointing this may be and sincerely apologize for any inconvenience caused. Please rest assured that we are actively exploring solutions to resume service and find the best way to support our US community.
We appreciate your patience and understanding during this time, and we look forward to welcoming you back as soon as possible.
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— The Sigma Sports Team