Bulls Sonic EN-R Team in the test: The sportiest Bulls E-MTB ever

Test / E-MTB: Equipped with a new full carbon frame including innovative geometry adjustment, a new Bosch drive and plenty of suspension travel, the Bulls Sonic EN-R aims to be the first genuine race E-MTB from the Cologne manufacturer. We have already been able to test the bike extensively.

Two years ago, Bulls in Cologne put the topic of e-racing on the agenda. With the Sonic Evo AM Team at the time, they also presented a corresponding bike for use - although it used the well-known all-mountain platform, it moved it in a much sportier direction with a CX race motor and robust components. Now for the 2025 model year, they are continuing on the course they have taken and, with the Sonic EN-R, are also presenting their own platform for very sporty e-MTB use for the first time.

The full carbon frame of the Bulls Sonic EN-R is a completely new development, with 170 mm of travel at the front and 160 (or 145 mm) at the rear. The bike is powered by the new Bosch CX Gen 5 motor, which is supported by a Bosch Powertube 600 battery in the down tube. The latter can be easily removed to the side, and the bike is also compatible with the PowerMore 250 range extender. This means that despite not having the new, large PowerTube 800 battery, there is a lot of variability in terms of batteries and range. The wheels are a mullet mix with 29 inches at the front and 27,5 inches at the rear. Incidentally, this makes it the only E-MTB in the current Bulls portfolio with mixed wheel sizes.

Bosch CX Gen 5 with 600 Wh battery

Like so many currently introduced E-MTBs, the Bulls Sonic EN-R also uses the new 5th generation Bosch CX motor. Even though the performance data has not changed compared to its predecessor and the weight saving of around 100 g is also quite small, the new motor scores with its refined response and, above all, significantly lower noise level. The integration of the somewhat more compact motor is a good feature of the new Bulls E-MTB, especially the solution with the solid aluminum skid plate is visually and technically well done. It not only protects the motor when it hits the ground, but also ensures that the drive unit remains well ventilated during longer uphill climbs and can deliver maximum performance for a long time.

geometry and travel adjustment

The Sonic EN-R offers a lot of variability, not just in terms of the battery, but also in terms of geometry and suspension travel. If you loosen the two screws on the top tube, the slide of the shock mount on the underside can be locked in three positions: flat, neutral and steep. This changes the steering and seat angles and also the bottom bracket height. Positive: The whole procedure is so quick that you can easily do it on the go, e.g. after a long uphill. If you also want to make changes to the suspension travel, there is also a flip chip on the rear triangle. This can be used to limit the 160 mm of suspension travel at the rear to 145. The conversion is not quite as simple as the geometry - whether you really want to unscrew the two small screws on the trail ... we wouldn't recommend it.

The geometry itself is modern and sporty. In the flat setting, the steering angle is 63,5°, but thanks to the steep seat angle, you sit pretty centrally. The reach is not particularly generous at a maximum of 475 mm, so if you like very long bikes, you might not be entirely happy with it. The biggest downside to the geometry, however, is the limited size selection: the Bulls Sonic EN-R is only available in two frame sizes - M and L. Particularly small or particularly tall riders are left out in the cold here - a shame!

Good equipment on the top model

We tested the Bulls Sonic EN-R in its top version for just under 10.000 euros. With tubes and without pedals in frame size M, it weighed just over 22,5 kg - a good weight considering the components used. Not only is the chassis made of RockShox ZEB Ultimate and Vivid Air Ultimate of the high-performance, robust variety, the same applies to the Mavic Deemax aluminum wheels and the Magura Gustav Pro brake system. Shifting is done with the elegant Sram XX Eagle Transmission, and there is also an 8-pin dropper post with over 200 mm stroke that is beautifully integrated into the frame.

The package is rounded off by the carbon handlebar-stem unit, which comes from the new in-house brand Rumble. The design limits adjustments after purchase, but saves a lot of weight. Important note: Due to the angular shape of the handlebars on the stem, the new Purion 400 cannot be mounted on the Sonic EN-R, which would otherwise have suited the bike very well.

The Bulls Sonic EN-R on the trail: Large reserves and a tight chassis

On the trail, the Bulls Sonic EN-R shows character and rides in a way that is untypical for Bulls. While the Cologne-based company's bikes have been known for their good nature and high level of comfort in the past, the new race bike is a different story: This is noticeable in both the geometry and the taut rear section, which provides good feedback from the trail but offers plenty of reserves for fast riding. The components used mostly work very well, and the choice of tires with the extra-soft rubber compound at the front is also impressive; however, heavier riders should consider a rear tire with a stable SuperGravity carcass.

The climbing capabilities of the new Bulls E-MTB are also unexpectedly powerful. The bike climbs excellently, especially in the steep geometry setting, which is of course also due to the new Bosch motor. Even if it doesn't score points with major leaps in performance, the improved sensor technology means it really sticks to your foot and is also a joy to ride thanks to its low noise level. In contrast to its predecessor, it also remains quiet on the trail - unfortunately, our test bike still rattled noticeably. According to Bulls, this is probably due to the battery cover on our pre-production bike.

You can find more detailed driving impressions in our test video on YouTube: