Why buy your bike from Sigma Sports?
Don't hesitate to reach out to us. It's our goal to answer all of your questions and offer the best advice from our experts. We’ll be happy to answer any questions you may have. Contact us now or visit us in-store.
All our bikes are fully built by our Cytech qualified mechanics. To find out more, see the Built, Checked, Tuned and Tested section below to see how we'll deliver your bike.
We offer FREE DELIVERY of your bike to your home or place of work. Once you've placed your order, our Customer Care team will be in contact to offer a convenient delivery date of your choice.
We've partnered with Pedalsure to offer you 30-DAYS FREE bike insurance on new bikes over £400. Visit our Cycle Insurance page to learn more and claim.
Trek Powerfly Sport 4 Equipped Gen 3 Electric Mountain Bike
Trek's best-value electric mountain bike, the Powerfly Sport 4 Equipped Gen 3 brings a powerful boost to more riders. Not only capable on the trails, but it also makes a great, rugged commuter, and lets you arrive to work without breaking a sweat. A durable aluminium frame is paired with an SR Suntour fork that has frame-size-specific, bump-absorbing travel, which can be locked out for speed across smoother terrain.
The frame houses a 500Wh battery and Bosch Performance CX motor system that provides assistance up to 15.5mph/25kph, and the long range means you can enjoy bigger adventures before a recharge is required. A Bluetooth-connected LED remote is included and it's easy to customise the system using the eBike Flow app. There are a number of modes to choose from depending on how much assistance you need, including a Walk Assist that makes pushing the bike easier, and an intelligent e-MTB mode that delivers power based on terrain so you can focus fully on the ride.
A Shimano Deore 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, and the XS and S have curved top tubes to lower the standover height.
Browse our range of Trek electric mountain bikes today.
- Trek Alpha Platinum Aluminium frame
- SR Suntour XCM 34 coil spring fork with 80/120mm travel and lockout
- Maximum compatible fork travel - 120mm (526mm axle-to-crown) (M-XL); 100mm (492mm axle-to-crown) (XS, S)
- Bosch's new smart system gives you all the same power and responsiveness with a new Bluetooth-connected LED remote and eBike Flow app that puts even more control and customisation at your fingertips
- The controller has Walk Assist and an intelligent e-MTB mode that automatically delivers the right amount of power based on your terrain
- Trek's Removable Integrated Battery (RIB) system looks great and is super user-friendly - it fully hides the battery in the frame for protection, makes it easy to remove the battery without tools and lets you mount a water bottle cage
- The bigger battery means you can adventure for longer between charges
- Shimano Deore drivetrain is precise and offers a wide gear range
- Tektro hydraulic disc brakes for all-condition stopping power
- Bontrager wheels and Bontrager LT4 Expert tyres - 27.5" on the XS and S, 29" on the M - XL sizes
- Battery Weight: 3kg (approximate)
- Battery Power: 500Wh
- Charge Time: 4.5 hours
|Frame||Trek Alpha Platinum Aluminium, Removable Integrated Battery (RIB), tapered head tube, Control Freak internal routing, Motor Armour, Boost148, 12mm thru-axle (curved top tube - size XS/S)|
|Fork||SR Suntour XCM 34, coil spring, preload, lockout, tapered steerer, 44mm offset, Boost110, 15mm thru-axle, 80mm travel (XS) / 120mm travel (S-XL)|
|Stem||Bontrager Comp, 31.8 mm, Blendr compatible, 7°, 50mm length (XS) / 60mm length (S,M) / 70mm length (L) / 80mm length (XL)|
|Handlebar||Bontrager alloy, 31.8mm, 15mm rise, 720mm width|
|Grips||Bontrager XR Endurance Comp, 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|
|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 - Bontrager Connection, double-wall, 32-hole, 20mm width, Presta valve / hub - Formula DC-511, 6-bolt, Boost110, 15mm thru-axle|
|Rear Wheel||Rim - Bontrager Connection, double-wall, 32-hole, 20mm width, Presta valve / hub - Bontrager alloy, sealed bearing, alloy axle, 6-bolt, Shimano 8/9/10 freehub, Boost148, 12mm thru-axle|
|Front Tyre||Bontrager LT4 Expert, reflective strip, wire bead, 60 tpi, 27.5x2.40" (XS,S), 29x2.40" (M-XL), clincher|
|Rear Tyre||Bontrager LT4 Expert, reflective strip, wire bead, 60 tpi, 27.5x2.40", (XS,S), 29x2.40" (M-XL), clincher|
|Saddle||Bontrager Commuter Comp|
|Seatpost||Bontrager alloy, 31.6mm, 12mm offset, 330mm length (XS, S) / 360mm length (M) / 400mm length (L-XL)|
|Pedals||Available to be purchased separately|
|Motor||Bosch Performance CX, smart system, magnesium motor body, 85Nm, 250w|
|Battery||Bosch PowerTube 500Wh, smart system|
|Charger||Bosch standard 4A, 230V, smart system|
|Electric Assisted Speed Limit||15.5mph / 25km/h|
|Maximum Weight||136kg / 300lb (combined weight of bicycle, rider and cargo)|
|Accessories||AXA Blueline tail light / integrated front light / Pletscher Comp Flex 18 kickstand / Trek Powerfly mudguards|
Built, Checked, Tuned and Tested
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.
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.