Trek Powerfly FS 4 Crimson/Lithium Grey

Powerfly FS 4 is a full suspension electric mountain bike built to tackle rugged trail adventures. The plush suspension setup soaks up rough terrain, and the powerful Bosch electric drive system boosts your capacity to crush climbs and mile after mile of singletrack.

You want to get out and explore more trails. You're looking for an e-MTB with trail-smoothing full suspension and the reliable, leg-boosting power of an electric drive system made specifically for the demands of off-road riding.

A durable aluminum frame that fully encases a long-range 500Wh battery, a powerful Bosch Performance CX (250Wh, 85 Nm) motor that helps you sustain speeds of up to 20 mph or 32 km/h, and an ergonomic Purion controller. Plus, a 120mm suspension fork, 100mm of rear travel, a 10-speed Shimano drivetrain, and a dropper post.

This full suspension e-MTB is comfortable, efficient, and fast on rough terrain. The powerful Bosch electric drive system makes it possible to tackle any climb you encounter and adventure farther than ever.

For e-MTB, full suspension is a game-changer: it soaks up rugged terrain so you can ride the Bosch pedal-assist system to its full potential
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—even on full suspension e-MTBs
The dropper post lets you lower your saddle on the fly so it's out of the way on descents
The Purion controller has Walk Assist and an intelligent eMTB mode that automatically delivers the right amount of power based on your terrain
Powerfly FS frames feature a curved top tube that makes standing over the bike easier. Plus, Smart Wheel Sizing means you'll get the fastest wheel that fits—29˝ wheels on larger frames, 27.5˝ wheels on smaller frames

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, colors, and materials.

*spec applies to all sizes unless otherwise noted

Frameset

Frame	Alpha Platinum Aluminium, Removable Integrated Battery (RIB), tapered head tube, internal routing, Motor Armour, magnesium rocker link, rack and mudguard mount, ABP, Boost148, 100 mm travel
*Fork	Size: XS , S SR Suntour XCR 34, air spring, LO R damper, hydraulic lockout, tapered steerer, 44 mm offset, oversized crown for eMTB, Boost110, 15 mm bolt-on thru axle, 100 mm travel
*Fork	Size: M , L , XL SR Suntour XCR 34, air spring, LO R damper, hydraulic lockout, tapered steerer, 44 mm offset, oversized crown for eMTB, Boost110, 15 mm bolt-on thru axle, 120 mm travel
Shock	SR Suntour Edge R, 190 mm x 45 mm
Max compatible fork travel	120mm (XS & S: 520mm axle-to-crown, M & up: 545mm axle-to-crown)

Wheels

Hub front	Bontrager sealed bearing, alloy axle, 6-bolt, Boost110, 15mm thru axle
Hub rear	Bontrager alloy, sealed bearing, alloy axle, 6-bolt, Shimano 8/9/10 freehub, Boost148, 12 mm thru axle
Skewer rear	Bontrager Switch thru-axle, removable lever
Rim	Alex MD35, tubeless compatible, 32-hole, 35mm width, presta valve
Spokes	14 g stainless steel
*Tire	Size: XS , S Bontrager XR3 Comp, wire bead, 30 tpi, 27.5x2.35"
*Tire	Size: M , XL Bontrager XR3 Comp, wire bead, 30 tpi, 29x2.30"
Rim strip	Bontrager TLR
Max tire size	Frame: 29x2.40" (XS & S: 27.5x2.60") Fork: See manufacturer

Drivetrain

Shifter	Shimano Deore M4100, 10 speed
Rear derailleur	Shimano Deore M5120, long cage
Crank	FSA Bosch CK-220, 36T ring, 165 mm length
Cassette	Shimano Deore M4100, 11-46, 10 speed
Chain	KMC X10, 10 speed
Pedal	VP-536 nylon platform
Max chainring size	Max: 46T, Min 34T

Components

Saddle	Bontrager Arvada, steel rails, 138 mm width
*Seatpost	Size: XS , S , M TranzX JD-YSP18, 100 mm travel, internal routing, 31.6 mm, 361 mm length
*Seatpost	Size: L , XL TranzX JD-YSP18, 130mm travel, internal routing, 31.6 mm, 425 mm length
Handlebar	Bontrager alloy, 31.8mm, 15mm rise, 720mm width
Grips	Bontrager XR Trail Comp, nylon lock-on
*Stem	Size: XS , S Bontrager alloy, 31.8mm, Blendr compatible, 7 degree, 60mm length
*Stem	Size: M , L , XL Bontrager alloy, 31.8mm, Blendr compatible, 7 degree, 70mm length
Brake rotor	Tektro, 6-bolt, 203 mm

Accessories

Battery	Bosch PowerTube 500
Charger	Bosch compact 2A, 100-240V, smart system
Controller	Bosch Purion
Motor	Bosch Performance CX, magnesium motor body, 250 watt, 85 Nm, 20mph or 32km/h max assist

Weight

Weight	M - 24.83 kg / 54.75 lbs
Weight limit	This bike has a maximum total weight limit (combined weight of bicycle, rider, and cargo) of 300 pounds (136 kg).