[Tested] BMC Trailfox AMP SX

In the start of the Winter, BMC North America kindly got us set up with their latest E-Bike innovation, the Trailfox Amp SX. The medium wheeled bike features a huge 170mm of travel up front, and retails for $7,999. Read on, and watch the video below to hear what we thought about the bike.

 

 

Specs

• Carbon front triangle/aluminium rear
• 170mm Front / 150mm Rear
• 27.5 / 650b
• Fox Float 36 Factory S-Ped Fork, Fox Float DPX2 Factory Shock
• Shimano XT Drivetrain
• DT Swiss H1900 35 Wheelset
• Shimano STEPS MTB E-8020, 500Wh, integrated battery
• 53.7 lbs / 24.3 kg (with pedals)

Based off the the Shimano STEPS platform, the bike features the E-E-8020, 500Wh, w/ integrated battery.

The Shimano display conveniently shows assist mode, speed, odometer, battery life, distance remaining, and can be connected via bluetooth to your smartphone.

To compliment the Shimano motor, and cranks, the bike features a full XT drivetrain.

The bike comes spec’d with the Fox Transfer post, a notable and reliable choice. We’re not huge fans of the lever, but as the post is cable actuated, you can easily upgrade to a Wolf Tooth, PNW Components, etc.

The Magura MT7 brakeset was one of the most impressive parts on the bike. When you’ve got a “monster truck” of a bike that’s racing down the trail, it’s extremely important to have adequate stopping power. We found the modulation to feel spot on, and that there was plenty of power to stop the 53.7 lb bike.

A Renthal bar and stem is a great thing to see on a stock bike. The two parts are crucial to a good feeling ride, and often are the first things to be replaced. In the case of our Trailfox Amp, our first choice of parts already came ready to rock on the bike.

The DT Swiss H1900 35 wheelset weighs 2203 g which is impressive for the heavy duty design. The wheels have a 35mm inner width and 40mm outer width. With all the rough terrain we rode, we never experienced any issues.

The frame has very clean lines, and the small gap in the headtube helps the bikes aesthetic from looking to over built.

The Fox DPX2 shock held its own, even in the most wild terrain. It’s evident that the custom tuning is crucial for the extra weigh the bike carries. The damping was very supple off the top, but ramped up into the travel so as to avoid bottoming out.

The Fox Float 36 Factory S-Ped Fork, which as an E-bike specific model is said to feature longer durability due to added material in the necessary places to improve stiffness. The damper is a GRIP2 and felt extremely sensitive in the start of its travel, ramping up adequately toward the end to handle the heavy impacts and sharp edged roots and rocks.

Geometry

Our size Medium test bike felt like the perfect fit, not falling above or below average bike sizing. The 445mm reach provides a fairly standard feeling cockpit, paired with a 65° head tube angle, the bike shares the numbers of most common ‘Enduro’ bikes on the market. At 440mm the chainstays are respectably short for an electric assisted bike, making wheelies and cornering easy. A 74° seat tube angle provides a solid climbing position, allowing for good power transfer to make the most of whichever assist mode you’re in.

On the Trail

The fantastic thing about the Trailfox AMP, is that even if the bike had no electric assist, the geometry, and components would make for a very playful and fairly aggressive trail bike.

When choosing between assist modes, we found our choice to be entirely dependent upon our length of ride, energy levels, and terrain. The Shimano STEPS platform provides an assisted ‘walk’ mode for off the bike hiking, followed by an ‘assist off’ setting, ‘Eco’, ‘Trail’, and ‘Boost’. The STEPS app allows for customization of the power output between the assist modes. We found the one we liked best is the factory default ‘Dynamic Mode’; its Boost level is set to high for maximum power assist and Trail level set to low which helps on technical climbs, so as not to accelerate to quickly and lose control. We grew to like the STEPS platform, only finding one gripe, the whining noise while heading up the hill, Brose systems (in Specialized E-Bikes) are silent motors, and we’d love to see that technology transfer over to other brands.

The Trailfox AMP excelled in the steep terrain, even if the riding surface was slippery due to dry conditions, or muddy. Touching briefly back on bike spec, the Vittoria Mota tires allowed for fairly low pressures, and coupled with being a 2.5″ front and rear width, provided a massive amount of traction, which was extremely confidence inspiring.

We found the bike easily slid into the so called ‘pocket’ of corners, remaining stable, and exiting with speed. The extra weight you find in electric assisted bicycles is often unwelcome, yet we actually felt the added weight in the Trailfox AMP provided reliable handling, and a more grounded feeling when in rough terrain.

Overall

A well thought out component spec, desirable geometry numbers, and a clean aesthetic led us to our final conclusions. If you are looking to ride the way you typically would ride on a non assisted bike, whether that’s technical downhill, loamy chutes, or flowing singletrack, the Trailfox AMP SX is likely one of the best E-Bikes on the market.

More at: BMC