The story of this e-bike goes like this: The fastest German enduro rider tries his hand at Christian Textor a few years ago, I also took part in the e-version of the Enduro World Cup. Here is the report. However, the e-MTBs from Bulls, the main sponsor at the time, were hardly designed for such extreme use. The racer's feedback therefore triggered the development of a new race enduro bike. Uncompromisingly made for maximum downhill speed, according to the developers.
"Texi" has not been riding for Bulls for two years now, but for YT. However, the bike inspired by his feedback has now also made it into the series. This is unusual insofar as Bulls, as a bike brand of the ZEG specialist trade association, is otherwise committed to bikes for the masses rather than top athletes. But what about the Bulls Sonic EN-R on the trail? Is the bike a pure extremo for racers or does it also cut a fine figure for mere mortals?
The facts about the Bulls Sonic EN-R Team
- Motor: Bosch CX, 85 Nm max. torque
- Battery: 600 Wh (removable)
- Frame material: Carbon
- Suspension travel: 170/160 mm
- Wheel size: 29/27.5 inch (Mullet)
- Frame sizes: M, L
- Price: 9999 Euro
- Weight: 21.96 kg (test bike in size L, EMTB measurement)
- Permissible total weight: 125 kg (manufacturer's specification)
- Available from January 2025
New Bosch motor and compact battery
As one of the first bikes with the new Bosch CX motor the Sonic EN-R was also on show at Eurobike. At that time, however, no details of the engine could be revealed. We now know: Like its predecessor, the new Bosch Performance Line CX offers 600 watts and 85 Newton metres at its peak. However, the ride feel has been noticeably improved compared to its predecessor. In addition, the motor no longer rattles downhill. As a downhill fan, the latter in particular is a major improvement.
There are two battery packs to choose from in the Bosch system. A large 800 offers maximum range and weighs around four kilograms. However, in favour of the best possible riding characteristics, Bulls opted for the smaller 600 (three kilograms) on the Sonic EN-R, which can be removed from the side of the frame. Despite the small battery, you don't have to worry too much about the range. In our first tests with the new 600, the new Bosch managed almost 1800 metres in altitude under full load. This means that even with the nominally small battery, the new Bosch outperforms most batteries from other manufacturers with around 720 watt hours. The Bosch system is operated with a minimalist combination of mini-remote and system controller. There is no display on board the Sonic EN-R, but if you wish, you can use an inductively charged smartphone with the Bosch app as a screen on the standard bike.
Maximum customisation: the geometry of the Bulls Sonic EN-R
Bulls wants the Sonic EN-R to be understood as an uncompromising racer. Is this also reflected in the geometry? Only in part, because the Sonic EN-R remains quite moderate in some values such as the seat angle, which is flattened by the seat post setback, and the reach. In others, the dimensions of the bike are simply unusual. The low stack in combination with the low handlebar/stem unit is particularly striking.
The special feature of the Bulls is its highly customisable geometry with two adjustment options. The front shock mount can be fixed in three positions via a slider under the top tube. This results in significant changes to the steering angle, seat angle, reach, stack and chainstay length. To put it simply: Steeper and longer in the reach with short chainstays for flat, slow courses and longer and flatter for steep and fast courses. The centre position should offer a balanced compromise.
In addition, the suspension travel can be reduced from 160 to 145 millimetres using two flip chips in the shock rocker. This results in only minimal changes to the geometry, but climbing performance in particular should benefit from the shorter stroke. In contrast to the quickly adjustable geo-adjustment with the slider, however, the conversion to the shorter stroke is time-consuming and therefore only practical on the trail in exceptional cases.
EMTB measurements at a glance (frame size M)
- Seat tube length: 437 mm
- Wheelbase: 1245 mm
- Reach: 441 - 452 mm
- Stack: 628 - 619 mm
- Steering angle: 62.6 - 64 degrees
- Seat angle: 76.5 - 77.5 degrees
- Chainstay length: 449 - 440 mm
The equipment of the EN-R Team Enduro
The parts on the top-of-the-range EN-R Team fit the intended use. Bulls uses top components from Sram and its subsidiary brand Rockshox for the suspension and gears. Gears are shifted with the XX transmission including matching carbon cranks. A Zeb Ultimate with 170 millimetres of travel is used at the front. The 160 millimetres at the rear are managed by the Vivid Ultimate shock. The Eightpins dropper post with a full 220 millimetres of travel also comes from the very top shelf. When it comes to the wheels, Bulls still leaves some room for improvement in terms of quality with the aluminium Deemax SL. However, some people might welcome the decision against carbon, especially for the downhill feel. Schwalbe's Tacky Chan in the soft Ultrasoft compound at the front rounds off the equipment.
- Fork / shock: Rockshox Zeb Ultimate / Vivid Ultimate
- Gear system: Sram XX Transmission (12-speed)
- Brakes: Magura Gustav Pro, 220/203 mm
- Wheels: Mavic Deemax Enduro SL
- Tyres: Schwalbe Tacky Chan Ultrasoft / Big Betty, Supertrail, 29x2.4/27.5x2.6 inch
- Special features: Integrated tool, double geo-adjustment, Monkey-Link interface for smartphone or headlights
Practical test: How the Bulls Sonic EN-R Team rides
An uncompromising race enduro bike for use in the E-World Cup? Anyone who knows the routes on which the professional athletes ride here will immediately have a clear picture in mind. Super steep uphills demand radical seat angles and long chainstays. For long and fast descents, many racers rely on a long reach and high stack in combination with very slack head angles. This provides a lot of speed downhill, but is often less fun to ride in everyday life.
Accordingly, you may be surprised when you swing your leg over the Bulls Sonic EN-R. Fortunately, the new Bulls doesn't take a completely radical approach. The seat angle is softened by the strong setback of the Eightpins dropper post to a moderate touring position. In combination with the low front end, the riding position is rather sporty and stretched out on the bike. The rear suspension provides plenty of traction on climbs. In combination with the new Bosch motor, a slipping rear wheel is rarely a problem.
However, the road bike-like saddle already feels unsuitable on flat terrain and offers hardly any rear support on steep ramps. On steep sections, the front also becomes too light too quickly. That's funny for experts, to accelerate out of tight corners in a power wheelie. For uphill challenges à la Enduro World Cup, however, anything but ideal. Nevertheless, if you set the geometry to steep, the Bulls Sonic EN-R becomes a little more controllable uphill and the steering is less sensitive. However, the basic character remains the same: Simply sitting on the bike and easily pedalling up the steepest climbs - that's simply not possible with the Bulls.
Strong rear triangle, quiet downhill
Downhill, the Sonic EN-R blossoms all the more. The superbly tuned rear suspension avoids a lame hoover feeling, but feels the ground sensitively and offers massive reserves. If you want, you can also fine-tune a lot using the extensive damper settings, from high and low-speed compression to hydraulic bottom-out. This is exactly what we want on an enduro bike! Weighing just under 22 kilograms, the Bulls also remains manoeuvrable and light-footed downhill and still provides a lot of confidence on rough straights.
There is also praise here for the slider for geo-adjustment. Just loosen the two screws by just under a turn, move the slider and tighten it again. Switching between the three positions is a breeze with the tool integrated under the top tube and brings noticeable changes to the riding characteristics. The spectrum ranges from extremely progressive (super-slack steering angle!) for fast tracks to good-natured and manoeuvrable for slower and flatter tracks.
The Bulls is also really quiet. Even going uphill, the motor only purrs discreetly. Downhill, instead of the motor, battery, chain or cables, you only hear the whirring of the tyres. Minor points of criticism: The Tacky Chan tyre at the front is already showing signs of wear and tear and didn't quite convince us in terms of traction. With a sharp limit range, it doesn't inspire much confidence. At the rear, fast riders should consider the puncture-proof Supergravity carcass instead of the Supertrail carcass on the E-Enduro. And we found the carbon cockpit (780 mm) with little rise to be less than ideal. Especially on steep descents, the low front end lacks a sense of security. Ergonomic adjustments are not possible without great effort due to the integrated solution. Our tip: 800 millimetre handlebar width and 25 to 30 millimetre rise would suit the otherwise successful bike much better.
EMTB evaluation of the Bulls Sonic EN-R Team
Strengths
- Light and quiet
- strong rear triangle
- great riding characteristics downhill
- Geo-adjustment in the blink of an eye
Weaknesses
- noticeable front wheel climb
- Front borderline low
- only available in M and L
- expensive
The BIKE conclusion
The new Bulls Sonic EN-R is expensive, but a real top bike! Light, powerful and quiet. We were particularly impressed by the suspension. However, the low handlebar/stem unit is a matter of taste and lacks composure on really steep climbs. On the other hand, the Bulls emphasises downhill fun.
Adrian Kaether
Editor
