BMC Trailfox AMP SX One Trailhammer in long-term test

Test: The BMC Trailfox AMPSX One is the durable top model from the Swiss, whose little brother we tested some time ago (BMC Trailfox SX Two). The top variant offers high-quality equipment and more suspension travel, but can the noble device also do more? And what about maintenance and the like? Should you have a piggy bank ready right away or are the components also suitable for everyday use?

BMC Trailfox AMP SX One: Fast and smooth running

Straight to the driving impression, in order to go into the components and their maintenance afterwards. Overall, we tested the BMC Trailfox AMP SX One over several hundred kilometers in different seasons, and thus also with large differences in the outside temperature. In addition, of course, in a wide variety of terrain.

The BMC Tratilfox AMP SX One shone on the climbs with outstanding climbing properties and, above all, grip. The 2,5 inch wide Vittoria Mota DH tires on the front and rear wheel provided that. The balanced steering angle of 65° also contributes to this. You always sit well in the saddle, even on steeper sections, and the bike is also very comfortable over long distances. In the size recommendation, BMC recommends size M for a body height of 181 cm, but also size L. We tested size M, which seemed a bit small to us on the track or uphill.

But different on the descent. Here the "small" size fitted a little better, although there is no mention of agility. The BMC Trailfox AMP plays all the trumps, especially on fast and rough trails. Wide tires for enough grip, Fox Factory chassis with Kashima coating and a low center of gravity. Thanks to the 170mm spring travel at the front and a full 150mm at the rear, there are enough reserves to forgive mistakes.

But as soon as it gets slower and significantly more technical, the Trailfox no longer stands out in the BMC quartet. It's incredibly stable straight ahead, but you have to "force" it into corners as soon as you reach a certain peak in the steering angle, it literally tilts into the corner. This property requires experience and sensitivity to tame the BMC Trailfox AMP SX One. If you have this, or if you have gotten used to the SX One, you can master it with pleasure.

BMC Trailfox AMP SX One: Drive and propulsion with Shimano STEPS E8000

The Shimano drive unit consisting of the STEPS DU-E8000 motor, the STEPS BT-E8020 battery, the STEPS SW-E7000-L switch and the STEPS SC-E8000 display offers everything an E-MTB heart desires. Sufficient power and torque, sufficient battery power and clean usability as well as sufficient information content on the display.

Here the STEPS E8000 series is used almost throughout, except for the switching unit. However, this is for ergonomic reasons and we feel it is a much better solution. This is how the Tiger for the seat post can be attached below and operated comfortably with the thumb.

In terms of performance, it was always delivered. Because of the 250 watts of continuous power and a maximum torque of 70 Nm, there was always enough support even for steep climbing passages. Even technical climbs could be mastered perfectly thanks to the easy-to-dosage trail mode. However, there is a small deduction in the volume of the Shimano STEPS E-8000 motor, because as soon as it is switched on, it is always present acoustically.

BMC Trailfox AMP SX One: How long does the battery last?

Fish from the factory are promised enormous range for the current batteries, which may also be feasible under laboratory conditions. But what good is all the theoretical range if it doesn't hold up in practice. Of course, the battery performance and thus the range depends on a wide variety of factors and external influences.

Above all, one thing was completely logical and understandable. The 504 Wh strong Shimano battery in the Trailfox AMP is sufficient, but not necessarily the capacity bolt in cold temperatures. In several identical test drives, we managed to empty the battery in a very short time. The lap was driven continuously with full support level (boost) and managed to drive the battery from 1% to 56% within 00:25,5:1090, 100 km and 0 hm. All this at outside temperatures between -5° and +10°. (These test drive(s) do not reflect standardized test cycles and are far removed from laboratory conditions) With summer temperatures outside, however, there was still about 15% remaining capacity in the identical test round.

Nevertheless, we found that the battery gradually loses capacity over the many test kilometers that we drove with the BMC. Here, care through clean loading and proper storage is absolutely recommended. That's the only way to get something out of the battery for a long time.

BMC Trailfox AMP SX One: components and maintenance

Suspension: Fox 36, Factory, GRIP2, Kashima, 170mm / Fox Float DPX2, Factory, Evol, Kashima, 150mm

The Fox Factory suspension is extremely sensitive and cleanly tuned. The Kashima coating is supposed to reduce friction, if only barely noticeable from our point of view, and thus achieve even better handling compared to the performance models from Fox. Visually, the elements appear to be of significantly higher quality thanks to the golden coating.

The e-bike-specific tuning of the entire chassis is optimally matched to the BMC Trailfox AMP SX One and leaves nothing to be desired. Nevertheless, in order to maintain performance, the chassis should be serviced annually. Wear and tear on the coating and the internal components can also be minimized in this way.

Brakes: Magura MT7 / 4-piston calipers and 203mm rotors front and rear

The Magura MT7 brake system can be finely dosed and can also be used as a throwing anchor if required. The 4-piston brake calipers grip the 203mm rotors without any problems and bring the almost 25kg heavy bolide to a standstill without any problems. The reach of the Magura 1-finger lever as well as the pressure point of the brake can be adjusted to the driver's wishes without tools directly on the brake lever. The Magura MT7 leaves nothing to be desired ergonomically. During our test drive, the brakes did not have to be bled or otherwise serviced once, and the wear on the performance brake pads was also limited over the entire test session.

Groupset: SRAM GX Eagle 12-speed

Rock solid and endless bandwidth. Since SRAM introduced the Eagle group, a number of model series have developed. After the SX and NX Eagle belongs the SRAM GX Eagle to the beginner switching groups with 500% bandwidth, but is not inferior in quality. Stable, a bit heavier and still precise. This is also reflected in the price and is therefore also very attractive in terms of wear and tear and replacement. The relative additional weight compared to the top variants is therefore only a minor problem with the e-bike.

Due to a branch in the rear derailleur, we had to change the rear derailleur and chain in our test. What can happen every day and you're happy not to spend another 500 € on the repair.

Seatpost: Fox Transfer with Raceface Trigger

Thanks to the Raceface Trigger, the solid Fox Transfer seat post with a travel of 150mm can be comfortably operated with the left thumb. This requires only minimal effort and the easy-to-move seat post also gives direct acoustic feedback as soon as it is extended. But the speed is ideal, because some seat posts serve as helmet ejectors. During our test, neither the cable nor the seat post required maintenance.

BMC Trailfox AMP SX One: geometry and features

The geometry of the BMC Trailfox SX One is a good mixture of enduro and trail e-bike, but the combination makes the bike appear too smooth-running and less agile.

Equipment:

Loom: Trailfox AMP SX- Twin Hollowcore – Advanced Pivot System, 12 x 148mm Thru-axle, 150mm travel
Material: Carbon (F), Al-13 Triple-butted aluminum (R), integrated battery pack
Engine: Shimano STEPS MTB E-8000, 250W, 70Nm
Battery pack: Shimano STEPS MTB E-8020, 500Wh, integrated
Fork: Fox 36, Factory, GRIP2, Kashima, 170mm
Mute: Fox Float DPX2, Factory, Evol, Kashima
Crank & Chainring: Shimano FC-E8000, 34T
Cassette: SRAM GX Eagle, 10-50T
Warp: SRAM GX Eagle
Rear derailleur: SRAM GX Eagle
Selector lever (drive): Shimano SW-E7000L
Trigger (rear derailleur): SRAM GX Eagle
brakes: Magura MT7, Storm rotors (203/203mm)
links: Renthal Fatbar V2.0 800mm
Stem: Renthal Apex 40mm
FoxTransfer: Fox Transfer
Saddle: WTB Silverado Comp 142
impellers: DT Swiss H1900 Spline
Tire: Vittoria Mota DH 2.5
Weight: 24,2 kg
RRP: € 7.999