Retailing at € 6,699, the SONIC EVO EN-SL 1 enters the race as the most affordable candidate in our huge 2023 eMTB group test with 30 bikes. Can the lightweight, full carbon taurine fight itself to the top of the test field with its new Shimano EP801 motor, big 750 Wh battery and automatic Shimano XT Di2 drivetrain?

BULLS SONIC EVO EN-SL 1 | Shimano EP801/750 Wh | 160/160 mm (f/r)
22.1 kg in size L | € 6,699 | Manufacturer’s website

If you don’t know BULLS, you must have been hiding under a rock. Rumor has it that there’s one of their retailers no more than an 8-minute walk away from you, no matter where you live in mainland Europe. BULLS is part of ZEG, Europe’s largest dealer cooperative, which counts over 1,000 stores across the continent. BULLS’ portfolio includes two eMTB ranges: the potent SONIC EVO models with Bosch motors, and the lightweight SONIC EVO SL bikes, which feature Shimano motors. In our 2022 budget group test under € 6,500, we tested the SONIC EVO AM-SL 1, which generates 140 mm of travel front and rear. Now it’s time for its bigger sibling, the SONIC EVO EN-SL 1, to show what it’s capable of. The EN suffix stands for enduro and identifies the range’s long travel models, which are designed for the rough stuff. Accordingly, the EN-SL 1 provides a generous 160 mm travel at the front and rear, paired with big 29″ wheels. The German bull is the only contestant in this test to rely on a new Shimano EP801 motor – except for the Orbea Rise, which employs the restricted RS version with 60 Nm of torque. This makes it compatible with Shimano’s fully automatic XT Di2 LINKGLIDE drivetrain. The BULLS come with countless interesting features, but more on those later.

For an overview of the test fleet head to the group test: The best eMTB of 2023 – 30 models in review

The price breaker with killer key figures – The BULLS SONIC EVO EN-SL 1 in detail

Retailing at € 6,699, the BULLS SONIC EVO EN-SL 1 undercuts this group test’s average price of € 11,151 by well over € 4,000. Are you still convinced that eMTB prices are getting out of hand? Despite being the most affordable bike in the entire test field, the SONIC EVO EN-SL 1 isn’t a cheapskate at all, standing up against the competition with some impressive stats. For starters, it features a stylish full carbon frame with a slim silhouette, which is partly due to the compact BMZ battery with carbon housing. Just like the ROTWILD R.X735, the Bulls features a battery with carbon housing, which doubles as the sidewall of the down tube. The 750 Wh battery can be easily removed from the top of the downtube at a 45° angle, no tools needed. Not only is this system extremely practical, but it also helps keep the weight down to a very reasonable 22.1 kg in size L. The motor is neatly integrated into the frame, and so is the charging port right above it, which is easy and intuitive to use. Both the data cable and shift cable housing are routed internally through BULLS’ in-house handlebars, ensuring a very tidy cockpit. Despite its sporty look, the BULLS SONIC EVO EN-SL 1 comes with countless everyday and touring features. One of them is the MonkeyLink mount, which allows you to install a headlight, like the Supernova M99, without using tools: just clip it in and off you go! The light draws its power directly from the bike’s main battery. A FIDLOCK bottle cage is discreetly integrated into the underside of the top tube, while additional mounting points allow you stow away your trail essentials directly on the frame. The standard kickstand mount adapter for the carbon swingarm and trailer approval make the SONIC EVO EN-SL1 an excellent companion for touring and everyday riding.

The missing link between monkeys and humans? The magnetic MonkeyLink mount holds the headlight securely in place and draws its power directly from the bike’s main battery.
The initial setup of the Shimano XT Di2 drivetrain with the E-TUBE app is a little more complex than with SRAM’s electronic AXS drivetrain. In return, you’ll get both semi- and fully-automatic shifting modes with Free Shift and Auto Shift functions.
Okay, fine! The new Shimano EP801 motor is hard to tell apart from the other EP8 motors in this group test, both in terms of looks and hard numbers. The biggest difference is the Fine Tune mode in the E-TUBE app, which allows you to create up to 15 different levels of support.

If you take a closer look at the spec sheet, you’ll quickly realise how the BULLS team managed to keep the price down. For instance, the RockShox suspension consists of a cheaper Lyrik Select fork and matching Super Deluxe Select+ shock, which offer far less adjustment than the flagship Ultimate model found on the Trek Fuel EXe, which is more than twice as expensive as the BULLS. Moreover, the levers of the four-piston Shimano brakes forgo the tool free reach and bite point adjustment – although the cheap 200 mm Shimano DEORE rotors still ensure powerful and reliable deceleration. What we’re really fond of is the eMTB-specific Mavic E-Deemax wheelset, which is used on far more expensive bikes in this test, like the FLYER, and delivers an impressive performance on the trail. Considering the price point, the BULLS leaves little to be desired but still struggles to keep up with our Best Buy Tip, the RADON DEFT 10.0, which is specced uncompromisingly for trail performance and only costs € 100 more.

Sloped! The big 750 Wh battery can be removed from the top of the downtube at a 45° angle, easily and without tools. The proprietary carbon housing ensures a beautifully slim down tube.
Select what? Unlike the name suggests, the Lyrik Select fork offers few adjustment options and poor response, which makes it a poor choice for rough trails.
The slim top tube features several mounting points for a bottle cage and accessories. The FIDLOCK cage disappears almost entirely into the recess, preserving the clean frame silhouette.


€ 6,699


Motor Shimano EP801 85 Nm
Battery BMZ 750 Wh
Display Shimano SC-EM800
Fork RockShox Lyrik Select 160 mm
Rear Shock RockShox Super Deluxe Select+ 160 mm
Seatpost Limotech Alpha 1 150 mm
Brakes Shimano DEORE BR-M6120 200/200 mm
Drivetrain Shimano DEORE XT Di2 1x11
Stem Poligon BULLS 50 mm
Handlebar BULLS Riser 785 mm
Wheelset Mavic E-Deemax 30 29"
Tires Schwalbe Magic Mary Super Trail Evo Soft/ Schwalbe Big Betty Super Trail Evo Soft 2.4/2.4

Technical Data

Size S M L XL
Weight 22.1 kg
Perm. total weight 130 kg
Max. payload (rider/equipment) 107 kg
Trailer approval yes
Kickstand mount yes (included)

Specific Features

FIDLOCK bottle holder
MonkeyLink light holder

Tuning tip: Get the Supernova M99 headlight for the Monkey Link mount for night tours

Off to the bullring – What is the BULLS SONIC EVO EN-SL1 capable of?

Using Shimano’s E-TUBE PROJECT Cyclist app, you can customise the motor’s behaviour to suit your needs and preferences. Alongside a basic mode, the EP801 motor features a fine tune mode, which allows you to create up to 15 different levels of support. Using the same app, you can customise the automatic mode of the Shimano XT Di2 LINKGLIDE drivetrain – although this process is slightly more complex. Now you’re all set to go! Quite frankly, the EN suffix is overkill for the SONIC EVO, which is a tad too nervous to deserve a big, fat enduro badge and conquer rough trails, making poor use of the suspension’s reserves. With fast, consecutive hits, the BULLS feels harsh and lacks composure and agility, while on steep descents, the 470 mm seat tube restricts freedom of movement. However, the nervous character is partly due to the RockShox Lyrik Select fork, which doesn’t work as sensitively as the flagship Ultimate model found on other bikes, like the Trek Fuel EXe and Berria Mako. Moreover, the Shimano EP801’s distinctive metallic clunking noise is amplified by the carbon frame, which acts as a resonating chamber.

Cruise Control: Once you’ve found a suitable setup for the automatic drivetrain, you can relax and cruise along with the BULLS SONIC EVO EN-SL 1, without having to worry too much about shifting gears.
Eye to eye with the wild bull: when riding over steps and ledges, the suspension seems to develop a life of its own, behaving just as unpredictably as a rodeo bull.

The BULLS feels a little more at ease on flowing trails but doesn’t seem to fully exploit its low system weight, failing behind the rest of the test field in terms of riding fun. However, as the only bike with a Shimano XT Di2 drivetrain, the BULLS has a cool party trick up its sleeve, allowing you to change gears without pedalling using the Free Shift mode. If you’re struggling through technical terrain, heading towards a steep climb or a jump, FREE SHIFT allows you to shift to a lighter gear with either a single or continuous click without losing your stable standing position. The system then prompts the EP801 Drive Unit to advance the drivetrain at the chainring and the rear derailleur to shift gears. This allows you to prepare for a challenging climb before you let the powerful BULLS grind its way up the hill with tons of traction at the rear. The SONIC EVO is a solid companion for relaxed tours and everyday riding situations, where the intelligent auto-shift mode changes gears automatically according to a preselected configuration. Moreover, the countless everyday features allow you to attach all sorts of accessories to your BULLS which, together with the somewhat plush suspension and comfortable pedalling position, ensures a high level of touring comfort.

When the going gets rough, you have to grab the bull by the horns and hold on tight.

Size S M L XL
Seat tube 410 mm 440 mm 470 mm 510 mm
Top tube 595 mm 615 mm 637 mm 660 mm
Head angle 65.0° 65.0° 65.0° 65.0°
Seat angle 74.5° 74.5° 74.5° 74.5°
Chainstays 450 mm 450 mm 450 mm 450 mm
BB Drop 23 mm 23 mm 23 mm 23 mm
Wheelbase 1,202 mm 1,223 mm 1,246 mm 1,271 mm
Reach 420 mm 441 mm 460 mm 481 mm
Stack 635 mm 635 mm 644 mm 653 mm
Helmet MET Roam MIPS | Glasses Poc Devour | Backpack USWE Flow 16L | Jersey Rapha Trail Technical Long Sleeve | Pants Rapha Trail Pants | Shoes Five Ten Kestrel Pro Boa | Gloves POC Savant Gloves

Who should take a closer look at the BULLS SONIC EVO EN-SL 1 and who should look elsewhere?

The BULLS SONIC EVO EN-SL 1 is a great choice for anyone looking for an affordable tourer and everyday companion. If you’re after a feature-rich eMTB with a big battery and comfortable suspension, that’s also suitable for the occasional trail stint, the BULLS might be exactly what you’re looking for. Shiftless cruisers with a dodgy back will also get their money’s worth. Sporty riders with a limited budget who spend most of their time on demanding trails should take a closer look at the Radon Deft 10.0.

Riding Characteristics


  1. unbalanced
  2. coherent


  1. cumbersome
  2. clever


  1. flop
  2. top


  1. low
  2. high


  1. demanding
  2. intuitive


  1. boring
  2. lively

Intended Use

Gravel roads

Technical climbs

Flowtrail descents

Technical descents

Conclusions about the BULLS SONIC EVO EN-SL 1

As the cheapest eMTB in our 2023 eMTB group test, the BULLS SONIC EVO EN-SL 1 entered the race with a massive handicap. Despite all odds, it proved to be a great option for budget-conscious riders who favour touring comfort and everyday features over trail performance. With its nervous trail handling, however, it cannot keep up with the sportier but also significantly more expensive eMTBs in this test.


  • Affordable price
  • Practical touring and everyday features


  • Very nervous handling on trails

You can find out more about at

The test field

For an overview of the test fleet head to the group test: The best eMTB of 2023 – 30 models in review

All bikes in test: Berria Mako Hybrid GT LTD (Click for review) | Bulls SONIC EVO SL EN-1 | Cannondale Moterra Neo Carbon LT1 (Click for review) | Flyer Uproc X 9.50 (Click for review) | Focus SAM² 6.9 (Click for review) | Focus JAM² 6.9 (Click for review) | Focus Jam² SL 9.9 (Click for review) | Forestal Siryon Diōde (Click for review) | Giant Trance X Advanced E+ Ltd (Click for review) | Haibike Lyke CF SE (Click for review) | Ibis OSO (Click for review) | KTM Macina Prowler Exonic (Click for review) | MERIDA eONE-SIXTY 975 (Click for review) | Mondraker Crafty Carbon XR LTD (Click for review) | Moustache Samedi 29 Game 11 (Click for review) | Orbea Rise M-Team (Click for review) | Orbea WILD M-LTD (Click for review) | Pivot Shuttle SL Pro X01 (Click for review) | Pivot Shuttle LT Team XTR (Click for review) | Radon Deft 10.0 (Click for review) | Rotwild R.X735 Ultra (Click for review) | Santa Cruz Heckler MX XO1 AXS RSV (Click for review) | SCOTT Lumen eRide 900 SL (Click for review) | Simplon Rapcon Pmax TQ (Click for review) | Specialized Turbo Levo Expert (Click for review) | Transition Repeater AXS Carbon (Click for review) | Thömus Lightrider E Ultimate (Click for review) | Trek Fuel EXe 9.9 XX1 AXS (Click for review) | UNNO Mith Race (Click for review) | Yeti 160E T1 (Click for review)

Did you enjoy this article? If so, we would be stoked if you decide to support us with a monthly contribution. By becoming a supporter of E-MOUNTAINBIKE, you will help secure a sustainable future for high-quality cycling journalism. Click here to learn more.

Words: Rudolf Fischer Photos: Mike Hunger

About the author

Rudolf Fischer

In his previous life Rudolf was a dab hand at promoting innovation, putting his brain behind big-ticket patent assessments that easily ran into six-or-seven-plus figures. These days, the self-confessed data nerd’s role as editor at DOWNTOWN and E-MOUNTAINBIKE is no less exciting. Given his specialism in connectivity, Rudolf’s often placed on the front line of future mobility conversations, but he’s also big into testing new bikes–both on the daily as a committed commuter and intensively for our group tests. The business economist graduate is as versatile as a Swiss penknife, and that’s no hyperbole. Away from two wheels, his background in parkour means he’s a master of front, side and backflips, plus he speaks German, English, French, Russian and a touch of Esperanto. Japanese remains woefully unmastered, despite his best home-learning attempts. Good to know: Rudolf’s sharp tongue has made him a figure of fear in the office, where he’s got a reputation for flexing a dry wittiness à la Ricky Gervais... interestingly, he's usually the one laughing hardest.