Innovative all-rounder in the test: Bull's Sonic Evo AM2

Test: With the presentation of the Sonic E-MTB models, Bulls caused quite a stir in 2020 (we reported). With innovative detailed solutions, consistent integration and new, holistic approaches, Bulls wants to redefine the E-MTB with this model series. We took a closer look at the attractively priced Sonic Evo AM2 model and wanted to know whether it would live up to its promise on the trail.

Bull's Sonic Evo AM2: The Facts

• Frame material: Aluminium
• Suspension travel: 150 mm
• Drive: Bosch Performance CX Gen4
• Battery pack: Bosch PowerTube (choice of 400, 500 or 625 Wh)
• wheel size: 29″ front wheel / 27.5″ rear wheel
• Weight: 24,2 kg
• Price: €3.799 (400Wh), €3.999 (500Wh), €4.199 (625Wh)

With 2 mm of travel, the Sonic Evo AM150 is in the category of all-mountain e-bikes (if you can categorize e-MTBs like that) and with a price starting at 3.799 euros it is quite attractive. Visually, it looks modern and made of one piece; voluminous tube shapes and a tidy look characterize the appearance. But it also knows how to please in the details.

Clever and innovative detailed solutions

At first glance, the Sonic Evo AM2 looks tidy. The proportions are harmonious, all cables run inside the frame and the drive and battery are beautifully integrated. The head tube area is strikingly harmonious. Thanks to the new lower head tube standard of 1.8" created by Bulls, the suspension fork fits very harmoniously into the voluminous head tube area of ​​the frame.

The cables for the rear brake, dropper post and gears are all routed into the frame on the right side and almost completely disappear until they reach their destination. Refreshing and not a matter of course: The display cable enters the frame via the headset and is therefore well protected. Together with the angled line outlets of the Magura brake levers, this results in a very tidy cockpit. There is also a MonkeyLink interface under the stem, which makes it easy to retrofit a suitable headlight - great!

Bulls also stays true to its harmonious lines on the rear end of the Sonic Evo AM2. The chain stays are massive and the seat stays are nicely aligned with the top tube – even in the larger frame sizes. While more and more manufacturers are covering up the bearing points, they are visible on the Sonic but are confidence-inspiringly large. A soft chainstay protection reliably protects the frame from damage by the chain and only on closer inspection can you see a mounting point for a side stand that is hidden by a cover. Die-hard riders probably won't use it, but it's "nice to have" and makes perfect sense given the wide range of buyers of e-MTBs.

In 2020 "state of the art" but by no means a matter of course is the integration of the speed sensor and the magnet. Bulls places the sensor at the end of the chainstay and picks up the signal via a magnet on the Magura brake disc. Not only does it become virtually invisible, twisting or even losing the magnet should be a thing of the past.

Elegant integration of motor and battery

The drive comes Latest generation Bosch Performance CX motor with a torque of 75 Nm. Thanks to the magnesium housing, it has a comparatively low weight of just 2,9 kg. In contrast to its predecessor, it is not geared by a factor of 2,5 and is therefore compatible with standard-sized chainrings. The motor fits neatly into the frame and by no means looks like a foreign body. Except for a few cooling openings, it is largely encased in plastic covers, while a robust skid plate protects against unwanted stone contact.

When it comes to integrating the battery, Bulls goes its own innovative way. The Bosch PowerTube battery is inserted into the down tube at a 45 degree angle and closed with an aluminum flap. The lock is easily accessible below the charging socket in the head tube area. Practical: The locking mechanism of the battery cover offers other options at the same time: Whether it's a drinking bottle, bag or even a folding lock, the possibilities are diverse thanks to the Fidlock mechanism.

By changing the lower battery holder, 400, 500 and 625 Wh PowerTubes can be used. The only downside: The smaller batteries (400 and 500 Wh) are in the same place at the upper breakpoint as the 625 Wh battery. Anyone hoping for better handling with a smaller battery due to a lower center of gravity and lower weight will be disappointed. With a smaller PowerTube, the center of gravity tends to move up despite the weight reduction.

For the display, Bulls uses the Bosch Purion for the Sonic Evo AM2. Placed on the left of the handlebar, it offers easy-to-read basic information such as charge level display, remaining range, speed and support level. If you prefer a color display or connectivity, you can switch to the Kiox display. However, the entire wiring up to the motor has to be re-laid.

geometry and equipment

When it comes to geometry, the Bulls Sonic Evo AM2 is right on trend. The steep seat angle paired with a spacious reach  and a steering angle of 66 degrees promise lots of driving pleasure. The chainstays are in the middle with a length of 450 mm. The wheel size is also modern: at the front, a 29-inch wheel with a tire width of 2.35 ensures good roll-over behavior with optimum steering precision. A 27.5 tire with a width of 2.6 inches is used at the rear and is supposed to convert the 75 Nm of the Bosch motor into propulsion.

The equipment is cheap, but chosen very sensibly. The suspension elements come from Suntour. The fork can be adjusted to the respective needs via air pressure, rebound and compression. The Edge LOR-8 air shock has a rebound adjuster and a lockout lever, which locks the shock by 80% and is intended to prevent rocking when going uphill. When it comes to the braking system, Bulls relies on Magura MT5 at the front and MT4 at the rear. These are combined with 203 mm brake discs.

The gearshift uses the new entry level Eagle technology from SRAM – SX Eagle. 12 gears, from 11 to 50 teeth are available and are switched using a one-click shift lever. This is intended to prevent unintentional shifting of several gears at the same time and thus extend the service life of the drive train. A 34T chainring does its job on the motor and the chain is safely guided by a chain guide.

The equipment at a glance:

On the trail

We were able to test the Bulls Sonic Evo AM2 extensively in the Bavarian Forest, the foothills of the Alps and in the Tyrolean Alps. From leisurely after-work laps to tough trail tours, the Sonic had to prove what it promised on paper - namely to be an all-rounder.

First of all: there were no range problems. Regardless of whether it is a 625 Wh battery or its smaller, lighter counterpart with 500 Wh, a second battery was not necessary, even for tours of 2.000 meters in altitude. With a moderate pace and sensibly chosen support levels, day trips of well over 100 kilometers were no problem - great!

When stationary, the Sonic Evo AM2 immediately awakens fun trail feelings. When you first sit down, this first impression is confirmed. You sit sporty and modern "in the bike" and feel comfortable right away. The comfortable saddle was also convincing on longer trips. However, the cockpit has to take criticism. Unfortunately, the handlebars only have a very slight offset (backsweep) backwards. In combination with the very hard grips, fingers and hands sometimes became numb. 

The powerful support of the motor is immediately noticeable on climbs. With its 75 Nm, the Bosch Performance CX feels more powerful than some competitors with more torque on paper. If necessary, he goes to work very sensitively and can be dosed perfectly. The E-MTB mode is the ideal support level in technical terrain. Depending on the pedal input, it supports gently or powerfully, so even steep sections can be overcome without spinning tires. The uphill qualities were limited a bit by the tires and the wheel mix. If it gets extremely steep, the Sonic tends to lift the front wheel. You can counteract this by shifting your weight forward, but this is usually at the expense of traction. In addition, the inexpensive Schwalbe Nobby Nic tires with their hard rubber compound reach their limits early on and are prone to punctures. If you want to use the full potential of the Sonic Evo AM2, you should think about more stable and, above all, softer tires as an upgrade.

When going downhill, you immediately notice the very balanced geometry. The handling is agile without losing stability at high speeds. The 29er front wheel converts steering commands precisely into changes of direction. But here, too, one notices that the tire reaches its limits when driving hard.

The Suntour suspension works very well and releases the 150 mm comfortably without rushing through the spring travel too much. We didn't use the lockout function. The undercarriage remains rocking stable even when open. The Magura MT Trail brakes have proven to be extremely powerful. Even on long descents we couldn't push them to the limit.

The Bulls Sonic Evo AM2 manages to live up to its visually appealing appearance on the trail. The geometry and orientation are not extreme - which is very positive. Because E-MTBs should do one thing above all: to offer a successful overall package to as wide a group of buyers as possible. Whether you are a beginner or a trail pro, if you are looking for an attractively priced E-MTB with a Bosch drive, you are in good hands with the Bulls Sonic Evo AM2.

The Bulls Sonic Evo AM2 on the WWW

https://www.bulls.de