BULLS advertise the new SONIC EN-R TEAM as a thoroughbred eMTB racer. It combines a mullet wheel setup and 170/160 mm of travel front and rear. BULLS’ new e-enduro racer relies on the new Bosch Performance Line CX motor and countless clever features. Read the full review to find out more.
BULLS have been manufacturing bikes since 1995 and, as part of ZEG – Europe’s largest specialist bicycle retail association – is one of the biggest bike brands in Germany. Their wide portfolio ranges from city bikes to road and gravel bikes, as well as E-MTBs, which tend to focus more on touring. But BULLS can do performance too. They proved this with the SONIC EVO AM in our big e-mountainbike comparison test with 27 eMTBs. Now BULLS are taking things a step further with the new SONIC EN-R TEAM, which is their race-focused e-enduro. It’s lighter than all other bikes in the SONIC range and relies on a new Bosch Performance Line CX motor and 600 Wh battery. With its mullet wheel setup and 170/160 mm of travel, it’s set to smash records on the trail. The sleek design and innovative geometry adjustments promise to make the SONIC EN-R TEAM a one of a kind in BULLS’ portfolio. We tested the 22.38 kg bike in the Dolomites and can tell you whether it’s worth the € 9,999 price tag.
The new 2025 BULLS SONIC EN-R TEAM in detail
With its bright-red paint finish on the top tube and the brushed alloy shock mount and skid plate, the new EN-R is a real head turner and makes a statement even when stationary. The white BULLS decals stands out against the matte grey downtube, rounding off the overall sophisticated look of the bike.
The cables are routed internally and disappear into the frame through the headset, which relies on 1.8-inch bearings. These not only allow for a sleek frame design but also provide extra space for the cables to run through the stem. The BULLS SONIC features a MonkeyLink 2.0 interface, which comes with an integrated Garmin charger. Unfortunately, we were unable to test this function, as our model was still a 3D-printed pre-production version.
BULLS clearly focused on e-enduro racing with the SONIC EN-R, and added their proprietary Powerstage tool on the bottom of the top tube. The tool can be easily removed with a simple 90° twist, even with gloves. That said, we were quite disappointed with the tool itself, because it only includes a 4 mm, 5 mm, and 6 mm Allen key despite its massive size. It’s supposed to be a minimalist, race-oriented tool, but with only three tools to choose from it’s anything but practical especially considering its huge dimensions. At least it doesn’t rattle on the trail.
A clever shock mount allows for quick trailside geometry adjustments using the Powerstage tool. Additionally, the integrated flip-chip provides even more flexibility for the bike – but more on this later.
Even though the 5th generation Bosch Performance Line CX motor looks almost identical to its predecessor on paper, still delivering 85 Nm of torque and 600 watts peak power, there are some exciting changes on the inside. In our in-depth review of the new CX drive you’ll find all details. The new Bosch motor is discreetly integrated into the frame and protected against impacts by an aluminium skid plate rather than a conventional motor cover,which also improves air flow.
The new Bosch motor is paired with a 600 Wh PowerTube battery, which, in typical BULLS fashion, can be removed from the side of the downtube. To do so, you’ll have to remove the battery cover by turning the bolt on the downtube half a turn using the 4 mm Allen key of the Powerstage tool. With the same key, now you can turn the slightly deeper battery lock another half turn to release the battery. Important: since the battery lock doesn’t have a spring, you’ll have to turn it back manually when reinserting the battery. This might sound a little complicated, but it works smoothly and isn’t fiddly.
If the 4 mm Allen key battery lock isn’t secure enough for you, you can opt to retrofit a proper battery lock, which requires a key to activate. Additionally, the battery can be expanded using Bosch’s optional 250 Wh Range Extender, which can be easily stored on a rail that fits into the bottle cage mounts on the downtube. The battery doesn’t necessarily need to be removed for charging, as the charging port is conveniently positioned at the intersection between the downtube and toptube, right next to the headset. However, BULLS didn’t quite manage to get the cover of the charging port right – it feels a bit cheap and rattles loudly while riding.
The Bosch motor is paired with a wireless, bar-mounted Bosch Mini Remote and a System Controller in the top tube. The latter provides minimal information about battery level and selected riding modes but fits well with the bike’s sporty orientation.
The chainstay protector is integrated directly into the chainstay, and prevents paint chips and chain slap.
The specs of the new 2025 BULLS SONIC EN-R TEAM
We tested the BULLS Sonic EN-R TEAM variant, which comes equipped with a 170 mm RockShox ZEB Ultimate fork. The production bike comes standard with the fork in Rockshox’s “Electric Red” finish, which rounds off the overall harmonious look. However, our test model was a pre-production version with a grey fork. A RockShox Vivid Ultimate shock controls 160 mm of travel at the rear. Both suspension elements offer easy adjustment options and deliver a tremendous performance on the trail. Shifting is taken care of by an electronic SRAM XX Eagle Transmission AXS drivetrain, which relies on a direct-mount rear derailleur. The latter draws its power directly from the bike’s main battery and is paired with an ergonomic SRAM EC AXS Rocker controller, which is integrated seamlessly into the cockpit.
MAGURA GUSTAV PRO four-piston brakes with 220/203 mm rotors (f/r) do stopping duties.They were tested thoroughly by our sister magazine ENDURO, and impressed with excellent modulation and powerful braking torque.
The SONIC EN-R comes equipped with a RUMBLE Altimate PRO Carbon one-piece handlebar/stem unit, which, at 780 mm, follows the current trend towards narrower bars. The one-piece design ensures a clean look but only allows for limited adjustments.
The EightPins NGS 2 dropper post is bolted directly to the frame and offers up to 265 mm of travel. The most striking feature, however, is the stepless adjustability. A small lever on the seat clamp allows you to easily adjust the height by opening or closing the lock. Despite the fixed integration, the post can be removed and replaced without issues when needed. In our test, however, we found the dropper post took some getting used to, as it requires you to unload the weight before dropping the saddle.
Mavic supply the Deemax Enduro SL aluminium wheelset, which is paired with a Schwalbe Tacky Chan tire in the Ultra Soft rubber compound and Super Trail casing at the front and a Schwalbe Big Betty in the same Super Trail casing and slightly harder, more durable Soft rubber compound at the rear. If you like to get rowdy on the trail, we recommend upgrading to the more robust Super Gravity casing, which offers better puncture protection and allows to run lower air pressures – more grip, baby!
Spec variants of the new 2025 BULLS SONIC EN-R
Alongside the SONIC EN-R TEAM version we tested, there are two other variants. All three models share the same carbon frame and are available in the same sizes. The one-piece cockpit is the same too.
The more affordable EN-R 2 model retails at € 7,999 and has a solid spec. The suspension consists of a 170 mm RockShox ZEB fork and RockShox Super Deluxe shock. Shifting is taken care of by a slightly more affordable but equally reliable wireless SRAM GX Eagle AXS Transmission drivetrain. TRP C2.3RX TRAIL brakes with a 220 mm rotor at the front and 203 mm disc at the rear ensure powerful, reliable deceleration. An EightPins H01 dropper post and Mavic E-Deemax wheelset with the same SCHWALBE tires as the top-tier model complete the package.
Retailing at € 6,799, the EN-R 1 entry-level model is the most affordable version of the BULLS SONIC EN-R. It features a 170 mm RockShox Domain Gold R 1.8 fork and RockShox Deluxe Select+ RL shock, which controls 160 mm of travel at the rear. Shifting is taken care of by an 11-speed Shimano DEORE XT drivetrain, which has a slightly narrower gear range. The Shimano DEORE brakes, combined with 220 mm rotors at the front and 203 mm at the rear, deliver far less braking power than the MAGURA GUSTAV PRO of the flagship model. LIMOTEC supply the Alpha dropper post, while Mavic provide the E-Deemax wheelset, which is paired with Schwalbe Magic Mary tires at the front and Big Betty at the rear. However, the tires come in the flimsy Performance casing, so we recommend upgrading to more robust tires.
The geometry of the new BULLS SONIC EN-R TEAM
The BULLS SONIC EN-R comes in just two frame sizes, M and L. Unfortunately, this means that shorter and very tall riders walk away empty handed – what a shame! Our test bike in size L combines 475 mm reach and 435 mm chainstays, which ensures balanced handling.
Now onto the highlight of the SONIC EN-R: the adjustable geometry. BULLS’ engineers came up with something special. On the top tube, there are two bolts that can be undone to move the shock mount. This allows you to adjust the head angle between 65.5°, 64.5°, and 64.0°. You can see the current setting on the shock mount and the top tube. The whole process is quick and easy, making it easy to change the geometry on the fly using the Powerstage tool specifically designed for this purpose. What’s particularly clever is that you don’t have to work in the dirt and no parts can get lost – a very practical solution for trailside geometry adjustments.
With this system, BULLS want to allow you to convert the SONIC EN-R from an efficient climber to a downhill machine during e-enduro races before a Power Stage. We tested the system ourselves and, unfortunately, we have to say that while it’s well-executed, the performance change is only marginal. We hardly noticed any difference between the different settings.
The flip-chip is integrated into one of the swingarm’s pivot points. To adjust it, you first have to loosen the big bolt, followed by two smaller ones. It’s important to note that there’s a small, conical spacer between the bearing and the shock mount, which must be positioned correctly. This adjustment alters the travel and allows you to switch between 160 mm (100% downhill-oriented) and 145 mm to improve climbing performance – all without affecting the bike’s geometry. However, this adjustment isn’t intended for on-the-go trail use but requires a steady hand and a bit of time – around 5 minutes, after which you can enjoy a coffee.
| Size | M | L |
|---|---|---|
| Reach | 455 mm | 475 mm |
| Stack | 612 mm | 630 mm |
| Chainstay | 445 mm | 445 mm |
| BB Offset | 12.5 mm | 12.5 mm |
| Seat tube | 435 mm | 465 mm |
| Headangle | 64° | 64° |
| Seatangle | 76° | 76° |
| Top tube | 591 mm | 615 mm |
| Head tube | 100 mm | 120 mm |
| Wheelbase | 1234 mm | 1263 mm |
The new BULLS SONIC EN-R TEAM on the trail
The BULLS SONIC EN-R places you centrally on top of the bike rather than integrating you between its wheels. While, on one hand, this position feels less stable, on the other hand it’s more efficient for pedalling. Riding uphill, the front of the SONIC EN-R remains planted on the ground, following steering input precisely, even on technical climbs. The powerful motor pushes you eagerly over roots and rocks, and engages and disengages more smoothly than its predecessor – nice! Although the firm suspension doesn’t always deliver optimal traction, the bike remains efficient on forest paths and less demanding uphills – no need to reach for the climb switch, as the rear suspension doesn’t bob. As previously mentioned, the geometry adjustment on the BULLS only slightly improves uphill performance; we barely noticed any difference.
Downhill, the SONIC EN-R feels reassuringly balanced, with the weight evenly distributed between the front and rear, even though you don’t feel integrated with the bike. The Sonic is a lot of fun on flowing trails, where the firm suspension and RockShox Vivid shock allow you to build up speed by pumping through rollers and berms.
However, when the trail gets rougher, the EN-R lacks composure. The firm suspension is to blame here, as impacts from the terrain are transferred to the rider almost unfiltered. While the RockShox Zeb Ultimate fork handles small, fast hits without a problem, once you pick up speed through rock gardens and root sections, the bike shakes you up, forcing you to work actively and to pick your lines precisely to avoid losing traction. This makes the bike less suitable for beginners and requires an experienced rider to enjoy the descent. On the other hand, the bike offers good support for botched landings, when taking off over a root, or on jumps and drops.
Who should take a closer look at the new 2025 BULLS SONIC EN-R TEAM?
The BULLS SONIC EN-R climbs efficiently and effortlessly. The upright pedalling position makes it ideal for longer tours, where comfort is key. Downhill, it shines on flowy trails, delivering plenty of fun and putting a big smile on your face. However, before tackling tougher and more technical trails, you should scout them first, as the bike demands precise line choice, making it less beginner-friendly.
Conclusions about the new BULLS SONIC EN-R TEAM
The geometry adjustment feature of the BULLS SONIC EN-R is an innovative idea, but unfortunately makes little difference to the bike’s trail performance. That said, the SONIC is lots of fun, especially on flowing trails. The upright pedalling position makes it great for long days in the saddle and an impressive climber. However, on technical trails, the bike’s lack of composure and firm suspension require an experienced rider. The geometry adjustment sadly brings almost no noticeable performance improvements, and the massive Powerstage tool proves is incredibly impractical. Nonetheless, we think the BULLS EN-R TEAM looks extremely good!
Tops
- Easy geometry adjustment
- Polarising design
- Fun on flow trails
Flops
- Tool
- Demanding handling on technical terrain
More info on the BULLS website.
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Words: Robin Ulbrich Photos: Peter Walker
