Trek Powerfly FS 4 Electric Mountain Bike Review

The Powerfly FS 4 electric mountain bike (e-MTB) is one of the several electric bike offerings from Trek Bikes, a large seller of electric bikes. This e-MTB is considered a Class-2 electric bike providing a maximum assistance speed of 20 mph (32 km/h) and features a Bosch Performance CX mid-drive motor paired with a large capacity 500Wh battery. The motor is on the powerful side and provides 85 Nm torque controlled by a Bosch Purion controller, which has a walk assist mode as well as a custom e-MTB mode instead of a tour mode. It gives plenty of power assistance, and the ample battery gives a decent range. As always range is determined by several factors.

A unique feature of this bike is a seat post that can be lowered on the fly to make downhill rides more comfortable and ergonomic. Online orders are delivered free to your local retailer for assembly. Some retailers will even deliver the assembled bike to your home.

The battery is removable for security and charging. Trek calls this a Removable Integrated Battery (RIB). It can be removed and replaced easily without tools. It can be charged with the included Bosch 2A, 100-240V charger. The sturdy aluminum frame comes in an attractive Crimson/Lithium Grey or Matte Gunmetal/Matte Black. The Crimson/Black frame is available online in Medium, Large, and Extra Large sizes. Each size features a 29-inch wheel and fork suspension that maxes out at 120 mm The Gunmetal/Black frame is available online in Extra Small, Small, Medium, Large, and Extra Large. The smaller sizes have a 100mm maximum suspension distance. The company website has a useful tool to determine the correct size for your height and leg length.

The chain, derailleur, and cassette are 10-speed. The weight of the bike is 54.75 lbs (24.83 kg). Maximum capacity is a typical 300 lbs (136 kg). The bike is pre-wired for optional lights.

Pros:

• Powerful Bosch motor
• Generous 500 Wh battery
• No tools required to remove/replace battery
• Dropper post for lowering seat on-the-fly
• Curved frame top tube for easier mounting
• Full suspension

Cons:

• Lights are optional

Verdict 5/5 stars

If you are looking for an attractive sturdy e-MTB, it is worth considering the Trek Powerfly FS 4. It is built with attractive features, and swapping batteries is possible for longer range. The price is reasonable. It is not the most inexpensive, nor is it the most expensive either. Trek makes excellent bikes, and some retailers will even assemble and deliver your bike if you order online. Since mountain bikes are not typically used for nighttime excursions, the lack of included lights should not detract from buying this bike.