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The Powerfly FS+ 4 800Wh Equipped is a robust, full-suspension electric mountain bike engineered for epic backcountry rides and multi-surface alpine terrain.
The Powerfly FS+ 4 800Wh Equipped is a robust, full-suspension electric mountain bike engineered for epic backcountry rides and multi-surface alpine terrain.
Trek

TREK Powerfly FS+ 4 Gen 5 800Wh Electric Full Suspension Mountain Bike in Mercury Dark Web

£4,150.00
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With Pre-Order, you can purchase the latest items added to our store in advance of them arriving with us.

Your Pre-Order is prioritised (at no additional charge); meaning that as soon as the product arrives with us, we can wrap it straight back up; ready for collection via Click & Collect or despatch to you — it often never even hits the stock room shelves!

Pre-Launch

With Pre-Launch, the date when we expect to receive the product ourselves is still a little too hazy to be confident in accepting Pre-Orders.

So, instead, you can submit your email address against the item you are interested in and we will email you as soon as stock arrives on the system.

Estimated Delivery & Collection Dates

Estimated Delivery & Collection Dates are given on Pre-Order and Pre-Launch products. They are for indication purposes only and can change at any time without notice.

The dates we provide are based on indications given by our suppliers. Whenever we get updated information from our suppliers we will endeavour to update the Estimated Delivery & Collection Dates provided on product pages.

We estimate this will be ready for despatch to you or collection via Click & Collect on Undetermined
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When you purchase this item, you will earn of rewards points to spend on your next purchase from us. You can spend your Rewards balance in-store & online.

Online Returns Policy

If you are not happy with any items purchased via our website, under Consumer Contracts Regulations you have the right to return any unused products for a refund or exchange within 30 days.

When the customer sends an item back to the company (or, when the company arranges for collecting from the customer), the company will process the returned item then notify the customer via email of the refund. The refund will be issued within 3 - 5 working days of the product being received by us, it may then take an additional 3 - 5 working days for the refund to be paid into the customers account.


If you’d like to return an item within the standard 30-day period and it’s in a suitable condition for resale, you have two simple options:

  1. Use Your Own Postage – Arrange your own return shipping back to us.

  2. Use Our Easy In-House Returns System

    • £10 for parts, accessories, and clothing

    • £50 for bikes

To start your return, please contact us at [email protected] and we’ll send you a returns label.

Please Note: Returns will only be accepted if they arrive back to us in original new condition, with all original packaging and tags still attached.

Return Address:

Team Cycles LTD
Studio 11B
Second Avenue
Team Valley Trading Estate
Gateshead
NE11 0NF

For items returned within the cooling off period...

  • By law, customers have the right to withdraw from the purchase of an item within 14 working days of the date on which the item is delivered.
  • Where you are withdrawing from your purchase within the cooling-off period, and there has been no error on our part, we will refund the cost of the item.
  • The company will not refund the cost of delivery or other services provided to the customer in connection with the purchase.
  • The cost of delivery back to the company is the responsibility of the customer.
  • Where we collect an item from you, we reserve the right to recover the costs of collection from you.
TERMS AND CONDITIONS
  • Returned goods should be unused, in a saleable condition and in their original packaging with all labels still attached. Team Cycles is entitled to refuse the return or deduct from a refund as a result of the product not being in the above condition.
  • We are only able to exchange like for like products. If you require a different item, you will need to opt for a refund and place a new order. All returns must have a completed returns form.
  • We will refund you to your original payment method.
  • Customised items cannot be returned. *
  • Please do not send your purchase back to the manufacturer unless you have been advised to.
  • Team Cycles customers have 30 days from date of delivery to return their orders.
  • Once we have received the returned goods we will refund you, by the method you used to pay for your order. This may take 5-7 working days to appear as cleared funds.

*Faulty customised goods (or goods that have been altered in any way) will need to be returned for inspection as customisation may void your warranty and therefore faults may not be covered.

WARRANTY

All products ordered from Team Cycles come with a full warranty which covers manufacturing faults and defects in workmanship. If you feel that your purchase has developed a fault, please contact our store for an assessment. To do this you will need proof of purchase.

If taking your product in store is not an option then please email our team on [email protected]. Please include photographs of your product (please keep below 20mb), your web order number (or copy of receipt) so we can immediately start to assess the issue.

PLEASE NOTE:

In some cases, the manufacturer/supplier may require to see the item(s) before repair or replacement can take place. If this is the case, we will inform you and arrange how to do this. All used items being returned to us must be cleaned for hygiene purposes.

On receipt of your goods we will carry out a full inspection and contact you within three working days of receipt.

Finance

Team Cycles (North East) Limited acts as a broker and not the lender and offers finance from Secure Trust Bank PLC T/A V12 Retail Finance. Team Cycles (North East) Limited is authorised and regulated by the Financial Conduct Authority, Registration Number 623982. Not all products offered by Secure Trust Bank T/A V12 Retail Finance are regulated by the FCA. Subject to age, status and affordability, minimum spend applies.

TREK Powerfly FS+ 4 Gen 5 800Wh Electric Full Suspension Mountain Bike in Mercury Dark Web

Season:2026

Brand:Trek

Code:57351GRY

The Powerfly FS+ 4 800Wh Equipped is a robust, full-suspension electric mountain bike engineered for epic backcountry rides and multi-surface alpine terrain. Built with a powerful Bosch Performance Line CX motor and a long-range 800 Wh battery, it delivers smooth assistance and incredible range so you can ride farther and climb higher without compromise.

With quality RockShox suspension (130 mm front / 120 mm rear), the FS+ 4 handles roots, rocks, and rough trail features with ease, while the Shimano CUES 10-speed drivetrain offers consistent, durable performance on demanding climbs and descents. Integrated accessories like mudguards, lights, rack, and kickstand make this e-MTB ready for bikepacking, daily commuting, or backcountry exploration straight out of the box.


Key Features

  • Bosch Performance Line CX Motor (85 Nm): Delivers smooth, responsive power for conquering steep climbs and technical trails with ease.

  • 800 Wh Bosch PowerTube Battery: Massive capacity for longer rides, bigger adventures, and extended range on full boost.

  • RockShox Suspension Package: 130 mm front travel (Recon Silver RL) and 120 mm rear travel (Deluxe Select+) for confident handling on rough terrain.

  • Shimano CUES 10-Speed Drivetrain: Durable and smooth shifting under load, optimized for e-bike torque.

  • Integrated Accessories: Equipped with front and rear mudguards, powerful built-in lighting system, MIK-compatible rear rack, and kickstand.

  • Smart Wheel Size: Sizes S and M feature 27.5" wheels for better agility; sizes L and XL come with 29" wheels for rollover performance and stability.

  • Dropper Post: Ride more dynamically and descend with confidence using the fitted dropper seatpost.

  • Removable Integrated Battery (RIB): Clean design with tool-free battery removal for easy charging on or off the bike.

  • Adjustable Geometry: Tuned for stability and confidence across varied terrain and riding positions.


Specifications Overview

  • Frame: Alpha Platinum Aluminium, full-suspension e-MTB frame with internal battery storage

  • Fork: RockShox Recon Silver RL, 130 mm travel

  • Shock: RockShox Deluxe Select+, 120 mm travel

  • Motor: Bosch Performance Line CX, 85 Nm torque

  • Battery: Bosch PowerTube 800 Wh, removable integrated design

  • Display: Bosch LED Remote with smart system compatibility

  • Drivetrain: Shimano CUES U6000, 10-speed

  • Brakes: Shimano hydraulic disc brakes

  • Wheels: Tubeless-ready rims with mixed or matched wheel sizing (dependent on frame size)

  • Tyres: All-terrain, wide-volume tyres for grip and comfort

  • Weight: Approx. 25–27 kg depending on frame size and configuration


Who It's For

The Powerfly FS+ 4 800Wh is ideal for riders who want a full-power e-MTB capable of all-day trail riding, mountain adventuring, and mixed-surface touring. Whether you're exploring remote fire roads, technical singletrack, or commuting over varied terrain, this bike offers the comfort, power, and range to do it all—fully equipped and ready to ride.

Technical Information

*Please note – spec applies to all sizes unless listed separately

Frameset
FrameAlpha Platinum Aluminium, Removable Integrated Battery (RIB 2.0), tapered headtube, guided internal routing, Motor Armor, angle-adjust headset, Mino Link adjustable geometry, adjustable leverage rate, 34.9 mm seat tube, ABP, UDH, rack and mudguard mounts, Boost 148, 120 mm travel
ForkRockShox Recon Silver, Solo Air spring, Motion Control damper, lockout, tapered steerer, 42mm offset, Boost110, Maxle Stealth, mudguard mounts, 130mm travel
ShockRockShox Deluxe Select R, 210x50 mm
Max compatible fork travelSee service manual
Wheels
Hub frontShimano TC500 alloy, CentreLock, 110x15 mm thru axle
Hub rearShimano TC500 alloy, CentreLock, 148x12 mm thru axle
Skewer rearBontrager Switch thru-axle, removable lever
*RimSize:S , M , L , XL
Bontrager Line TLR 30, Tubeless-Ready, 28-hole, Presta valve
Size:S , M , L , XL
Bontrager Line TLR 30, Tubeless-Ready, 32-hole, Presta valve
Spokes14 g stainless steel, black
*TyreSize:S
Bontrager Gunnison Pro XR, Tubeless-Ready, wire bead, 60 tpi, 27.5x2.40"
Size:M , L , XL
Bontrager Gunnison Pro XR, Tubeless Ready, dual compound, aramid bead, 60 tpi, 29x2.40"
Tyre partBontrager TLR sealant, 180 ml/6 oz
Rim stripBontrager TLR
Max tyre sizeFrame: 29x2.50" (S: 27.5x2.50"), Fork: see manufacturer
E-system
BatteryBosch PowerTube 800 Wh, smart system
ChargerBosch standard 2A, 230V, smart system
ComputerBosch Purion 200
MotorBosch Performance Line CX, 20 mph / 32 km/h max assist (25 km/h max assist in EU and APAC)
Drivetrain
ShifterShimano U6000, 10-speed
Rear derailleurShimano CUES U6000 GS
CrankFSA Bosch CK-220, 36T ring, 165 mm length
ChainringFSA, 36T, steel
CassetteShimano CUES LG300, LINKGLIDE, 11-48, 10-speed
ChainShimano LG500, 9/10/11-speed
PedalVP-536 nylon platform
Max. chainring size1x: 38T
Components
SaddleBontrager Verse P3, steel rails
*SeatpostSize:S
Bontrager Line Dropper, 100mm travel, MaxFlow, internal routing, 31.6 mm, 310 mm length
Size:M , L , XL
Bontrager Line Dropper, 170 mm travel, MaxFlow, internal routing, 31.6 mm, 450 mm length
HandlebarBontrager Comp, alloy, 31.8 mm, 40mm rise, 780 mm width
*GripsSize:S , M , L , XL
Bontrager XR Trail Comp, nylon lock-on
Size:S , M , L , XL
Trek Line Comp, nylon lock-on
StemBontrager Comp, 31.8 mm, Blendr compatible, 7-degree, 50 mm length
Head setFSA IS-2, 1-1/8" top, 1.5" bottom
BrakeTektro Gemini SL 4 piston hydraulic brake
Brake rotorTektro, CentreLock, 203 mm
Rotor sizeMax brake rotor sizes – Frame: 220 mm, min 180 mm, Fork: see fork manufacturer
Accessories
Weight
Weight limitThis bike has a maximum total weight limit (combined weight of bicycle, rider and cargo) of 136 kg (300 lb).

We reserve the right to make changes to the product information contained on this site at any time without notice, including with respect to equipment, specifications, models, colours, materials and pricing. Due to supply chain issues, compatible parts may be substituted at any time without notice.

Bike and frame weights are based on pre-production painted frames at time of publication. Weights may vary in final production.

Sizing Information
SizeRider HeightInseam
S

155 - 165 cm

5'1" - 5'5"

74 - 78 cm

29" - 31"

M

165 - 176 cm

5'5" - 5'9"

79 - 83 cm

31" - 33"

L

177 - 188 cm

5'10" - 6'2"

84 - 89 cm

33" - 35"

XL

188 - 195 cm

6'2" - 6'5"

89 - 91 cm

35" - 36"

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