The new Brose Drive S Mag motor, 750 Wh battery capacity, 150 mm travel – on paper, the key figures of the BULLS E-STREAM EVO AM 4 27.5+ sound almost too good to be true – all at the competitive price of € 5,499. We’ve put the E-STREAM EVO AM through its paces to find out whether it can meet these expectations.
€ 5,499
The BULLS E-STREAM EVO AM 4 27.5+ is the flagship model of the range, but at € 5,499 it costs about the same as other manufacturers’ mid-range models. However, when looking at the build spec, it becomes clear that Bulls has put more emphasis on good value for money than high-end performance when choosing the components. The suspension consists of a 150 mm FOX 36 Rhythm fork, and a FOX Float DPS shock providing the same amount of travel at the rear. Shifting is taken care of by a Shimano XT drivetrain, while the powerful Magura MT5 brakes are responsible for deceleration – all in all, solid components with nothing much to criticise.
The highlight of the BULLS E-STREAM EVO AM 4 is undoubtedly the motor. At the heart of the aluminium frame is the new Brose Drive S Mag, which with its natural power delivery and massive power output, is the current benchmark for eMTB motors. The motor is fed by an equally impressive and neatly integrated 750 Wh battery, which can be easily removed if necessary.
The BULLS E-STREAM EVO AM 4 27,5+ in detail
Using Bull’s Monkey Link system, the E-STREAM EVO is compatible with lights, reflectors and mudguards, allowing you to connect the lights to the bike battery. Optionally, the E-STREAM EVO AM 4 can be ordered with the Connect C GPS module, which offers a wealth of features such as navigation, tracking your ride data or adjusting the support levels.
Fork Fox 36 Rythm 150 mm
Shock Fox Float DPS 150
Drivetrain Shimano XT/SLX
Motor Brose Drive S MAG
Battery BMZ Super Core 750 Wh
Brakes Magura MT 5 203/180 mm
Handlebar Bulls 760 mm
Stem Bulls 60 mm
Seatpost Kind Shock Lev 150 mm
Tires Schalbe Magic Mary / Nobby Nic 2.8″
Wheels Bulls AS-T35
The front end is very low with a stack height of 603 mm in size L, and in combination with the relatively short reach, the BULLS is very compact. On the trail, the bike feels very front-heavy and robs you of confidence on the descents.
When the brakes are adjusted appropriately, the XT shifter with its gear indicator needs to be moved very far inwards and becomes hard to reach – the same applies to the motor remote on the opposite side.
With the help of the Monkey Link system, you can easily convert the BULLS into a commuter bike, but the finishing details such as on the seat clamp seem like a half-hearted effort.
The large 750 Wh battery offers seemingly endless range! Unfortunately, its length also shifts the bike’s centre of gravity upward, which negatively affects the handling.
The magnetic cover of the charging port is so neatly integrated that we had a hard time finding it the first time!
The remaining componentry is somewhat rudimentary and the same applies to many of the frame’s details such as the cable routing. The narrow cockpit looks crowded and the awkward combination of brake levers, shifters and motor remote are limited in their ergonomic adjustability. The lower-end componentry and the large battery are also noticeable on the scale: the Bulls weighs in at just under 25 kg.
The geometry of the BULLS E-STREAM EVO AM 4 27,5+
| Size | 41 | 44 | 49 | 54 |
|---|---|---|---|---|
| Seat tube | 410 mm | 440 mm | 490 mm | 540 mm |
| Top tube | 590 mm | 604 mm | 623 mm | 642 mm |
| Head tube | 110 mm | 110 mm | 110 mm | 110 mm |
| Head angle | 67.5° | 67.5° | 67.5° | 67.5° |
| Seat angle | 74.0° | 74.0° | 74.0° | 74.0° |
| Chainstays | 460 mm | 460 mm | 460 mm | 460 mm |
| Bb Drop | 7 mm | 7 mm | 7 mm | 7 mm |
| Wheelbase | 1177 mm | 1191 mm | 1212 mm | 1233 mm |
| Reach | 421 mm | 435 mm | 450 mm | 465 mm |
| Stack | 590 mm | 590 mm | 603 mm | 603 mm |
The BULLS E-STREAM EVO AM 4 27,5+ on the trail
The E-STREAM EVO AM climbs excellently, it keeps enough weight on the front wheel at all times and the easy modulation of the Brose motor makes short work of even the steepest climbs. The low front end counteracts the quite slack seat tube angle, but tall riders will still feel like they’re riding too far over the back wheel. With its huge 750 Wh battery, the BULLS is predestined for long rides, so it’s no wonder that it gets used as a “camera bike” at the legendary Absa Cape Epic stage race.
The Brose Drive S mag in combination with the 750 Wh battery is hard to beat, long distance riders will get their money’s worth with this motor
The bike no longer performs as well when you point it downhill, unfortunately. The geometry of the BULLS is very compact, the front end is low and the front triangle is relatively short. In combination with the high centre of gravity caused by the long battery, the handling feels very front-heavy and a bit wobbly. The 2.8″ wide tire on the front feels outdated and further enhances the effect of the wobbly, front-heavy handling, making the steering feel sluggish and imprecise. It is difficult to find the right balance on demanding trails, feeling more like you’re sitting on the bike rather than “in” it. The dropper post offers only 125 mm drop, unnecessarily limiting your freedom of movement on the bike.
The suspension performs comfortably; the affordable FOX fork responds sensitively to small impacts and delivers a solid performance on harder hits. The rear linkage is generous with its travel; on bigger hits, the shock quickly reaches the end of its travel. The powerful Magura MT5 brakes perform excellently, never having trouble bringing the bike to a halt, but we would have liked a large 203 mm rotor at the rear as well.
Conclusion
Paired with the huge 750 Wh battery and the Brose Drive S Mag motor, the Bulls E-STREAM EVO AM 4 27.5+ offers outstanding performance in terms of the electronic assistance. Unfortunately, the cockpit is crowded and the geometry is not designed for real trail riding. There are other eMTBs that are significantly more capable in demanding terrain. If you mainly intend to go on long, comfortable cruises on forest roads, the Bulls delivers a strong overall package at a very attractive price.
Tops
- excellent motor
- battery capacity
- powerful brakes
Flops
- unbalanced handling
- little attention to detail
More info: bulls.de
This article is from E-MOUNTAINBIKE issue #017
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Words: Moritz Dittmar Photos: Finlay Anderson
