Powerfly 4 is our most affordable electric mountain bike. It's built with parts that hold up, like a smooth-shifting Shimano drive train, and a powerful Bosch motor. Plus, it features our user-friendly Removable Integrated Battery (RIB) system that's fully encased in the frame yet doesn't require tools for removal. This bike expands your boundaries and lets you travel to destinations that you never thought you'd reach on a mountain bike.

You're sold on the e-bike revolution and want the capability and versatility of a mountain bike at a price that doesn't resemble the car you're trying to use less. You want bigger, better off-road adventures, and know that an e-MTB with the latest user-friendly tech is the best way to get them.

A tough yet refined aluminium frame that fully encases a long-range 500 Wh battery for sleek looks, a Bosch Performance CX (250 W, 85 Nm) motor that assists up to 25 km/h, a Bosch Purion controller, a 1x10 Shimano drivetrain and a suspension fork with lockout. Plus, Smart Wheel Sizing means riders of every size get a great fit - 29? wheels on larger frames, 27.5? wheels on smaller frames.

Our most affordable electric mountain bike comes with the same powerful Bosch motor and intuitive controller as our most expensive e-bikes, with a smaller battery and parts chosen to give you great value.
- 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 remove the battery without tools and lets you mount a water bottle cage
- This bike expands boundaries: the top-notch Bosch system is equally suited to commuting, recreation and a ridiculously fun time on the trails
- The Purion controller has Walk Assist and an intelligent eMTB mode that automatically delivers the right amount of power based on your terrain
- It's equipped with an external charging port for easy charging on or off the bike
- You can boost your Powerfly's utility by adding a rack and mudguards, plus built-in wiring lets you easily install lights powered by the motor

Will my bike have a curved top tube?
Smaller frames (S) have a top tube that dips down as it approaches the seat tube. This design makes for a lower standover height, which is good for shorter riders because it allows them to straddle their bike more easily. The larger frames (M and ML) have a straight top tube because taller riders with longer legs typically don't have the same issues with standover height.

Bosch Performance Line CX motor
The Bosch Performance Line CX sets the standard for eMTB performance with up to 85 Nm of torque and an intelligent eMTB mode with Extended Boost that automatically adjusts the amount of assist based on the terrain.

Removable Integrated Battery
RIB is a one-piece battery and cover with a built-in handle that can easily be removed and re-installed in the frame with no tools and no hassle. It's the most convenient way to remove your battery for transport, security or just easier charging.



What is the range?
To see how far you can ride your electric mountain bike on a single charge, check out Bosch's range calculator. We've auto-filled the variables for this bike model and the average rider, but you can make adjustments to get your most accurate estimate.