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.
Save up to 47% with any one of our 11 Cycle to Work partners, and get the health benefits of a new bike in exchange for tax free salary sacrifice. To find out more about our various partners and how to apply click here.
Choose between Free Bike Delivery - to your home or place of work - or our new Premier Bike Delivery Service £99.99 and have your bike delivered "ready to ride" and set up to your measurements with seatpost and pedals adjusted on arrival by a qualified bike mechanic. Either way, our Customer Care team will be in touch to arrange a delivery date to suit you.
We've partnered with Laka to offer you 30 days free bike Insurance on your new bike purchase over £400. Click here for more info and find out how to claim.
Trek Powerfly 4 Womens Electric Mountain Bike 2020
Trek’s Powerfly 4 Womens Electric Mountain Bike uses Bosch’s latest 250W Performance CX motor and 500Wh battery to provide extra assistance when required, making short work of steep hills and tricky trails. With four assistance modes for when riding and a Walk mode, the powertrain can be adjusted on the fly via the handlebar controller so that help is always to hand. The battery is easy to remove without recourse to tools, making recharging it away from the bike simpler.
An aluminium frame with Motor Armor, internal cabling and rack bosses and a 120mm travel SR Suntour XCM 34 suspension fork forms the chassis for the bike, with modern ebike specific geometry ensuring both comfort and predictable handling off-road. The two smaller sizes benefit from 27.5” wheels and the larger options use 29” wheels so that the handling remains consistent, and the 2.35” wide Bontrager XR3 Team Issue tyres provide great grip in both sizes. Shimano 9-speed Acera/Altus components are both highly reliable and easy to operate, giving quick access to the range of gears available whilst Tektro’s HD-M275 hydraulic disc brakes offer great stopping power from just a light touch of the lever.
Highlights
- Trek Alpha Platinum Aluminium frame with RIB
- SR Suntour XCM 34 fork with 120mm of travel
- Shimano Altus 9-speed groupset
- Tektro HD-M275 hydraulic disc brakes
- Size-specific Bontrager wheels with 2.35” wide tyres
- Bosch Performance CX 250W motor and 500Wh removable battery
Technical Specification
| FRAME | Trek Alpha Platinum Aluminium, Removable Integrated Battery (RIB), tapered head tube, Control Freak internal routing, Motor Armor, Boost148 |
| FORK | SR Suntour XCM 34, coil spring, preload, lockout, tapered steerer, 44mm offset, Boost110, 15mm thru-axle, 120mm travel |
| STEM | Bontrager alloy, 31.8mm, 7 degree |
| HANDLEBAR | Bontrager alloy, 31.8mm, 15mm rise |
| FRONT BRAKE | Tektro HD-M275 hydraulic disc |
| REAR BRAKE | Tektro HD-M275 hydraulic disc |
| BRAKE LEVERS | Tektro HD-M275 hydraulic disc |
| FRONT DERAILLEUR | N/A |
| REAR DERAILLEUR | Shimano Acera M3000, Shadow design, long cage |
| SHIFT LEVERS | Shimano Altus M2010, 9-speed |
| CASSETTE | Shimano HG200, 11-36, 9-speed |
| CRANKSET | FSA 310, 15t with chain guard, |
| FRONT WHEEL | Formula DC-511, 6-bolt, Boost110, 15mm thru-axle hub with Bontrager Connection, double-wall, 32 hole, 20mm width, Presta valve rim |
| REAR WHEEL | Bontrager alloy, sealed bearing, alloy axle, 6-bolt, Shimano 8/9/10 freehub, Boost148, 12mm thru-axle hub with Bontrager Connection, double-wall, 32 hole, 20mm width, Presta valve rim |
| FRONT TYRE | Bontrager XR3 Team Issue, Tubeless Ready, Inner Strength sidewall, aramid bead, 120 tpi, 2.35 clincher (27.5” XS, S / 29” M, L) |
| REAR TYRE | Bontrager XR3 Team Issue, Tubeless Ready, Inner Strength sidewall, aramid bead, 120 tpi, 2.35 clincher (27.5” XS, S / 29” M, L) |
| SADDLE | Bontrager Ajna 1 |
| SEATPOST | Bontrager alloy 31.6mm |
| BATTERY | Bosch PowerTube, 500Wh |
| CONTROLLER | Bosch Purion |
| MOTOR | Bosch Performance CX, 250W, 75Nm, 25kph max assist |
| WEIGHT LIMIT | 136kg (bike, rider and cargo) |
| MANUFACTURER CLAIMED WEIGHT | 23.8kg size small |
| Electric assisted speed limit | 15.5 mph / 25 km/h |
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. 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.
Unable to display Reviews due to Privacy Settings.
Adjust your Cookie Preferences to Opt-in "YES" to "Functional Cookies".
Unable to display Q&A due to Privacy Settings.
Adjust your Cookie Preferences to Opt-in "YES" to "Functional Cookies".