E-MTB / Test: We finally had the opportunity to test the Bulls Vuca Evo AM 2 with the new Pinion MGU over a longer period of time. In addition to the bike itself, we also wanted to take a closer look at the drive unit after the initial “wow effect” from the summer had faded a bit.
The Pinion MGU caused a sensation on the e-bike market in the summer. The idea of combining a mid-engine with a gearshift unit was a long-awaited innovation for many. Although we had the opportunity to test some bikes with it when the drive was launched, these tests were quite limited in time and often in unsuitable frame sizes. With the Bulls Vuca Evo AM 2 we finally had the chance to test an almost final E-MTB with Pinion MGU in a suitable frame size in detail in the right terrain. In this case, “almost series production” means that the drive software and the built-in display in particular do not yet fully correspond to the final condition. Accordingly, we will only discuss this in passing.
In short, the Pinion MGU is a combination of a 12-speed gearbox with an impressive gear ratio range of 600% and a mid-engine that, according to Pinion, offers a comparable torque of 85 Nm, similar to most common mid-engines on the market . However, in our performance measurements, the Pinion MGU proved to be stronger than many competitors on the market, which was also evident in practical use.
In terms of weight, the entire unit is around 4,1 kg, compared to a conventional mid-engine and a corresponding derailleur gear, which is omitted here, it is only a few hundred grams more. Instead of a rear derailleur, the bike has a belt drive, making maintenance much easier. Pinion itself states that the system can run almost maintenance-free for up to 10.000 km before an oil change is required. Even though we haven't been able to verify this yet, we hope that Pinion is right about this because it would be a real innovation on the market. The Bulls Vuca Evo AM 2 in frame size L and the 720 Wh battery weighs just under 24,7 kg, which is due to the generous equipment with 150 mm of travel at the front and rear, robust tires, 29-inch wheels and a Fox 38 Front fork is quite a respectable weight.
Carbon main frame with innovative rear triangle
The main frame of the bike is made of carbon, while the rear triangle is made of aluminum. Visually, the damper linkage is reminiscent of the well-known E-Stream Evo models, but the design on the Vuca Evo AM comes with an additional linkage. Bulls calls this the “Four Link Swingarm” – basically a very complex supported single-joint arm. This design has several advantages, most notably the one-piece rear triangle without bearings. This saves weight and increases rigidity. In addition, you can drive the shock with very little pressure, which will particularly please heavier riders: for around 85 kg at around 30% sag we only needed 150psi. The high permissible total weight of 150 kg also fits in with this. Additionally, you can even attach a trailer, although this may not be the bike's primary use.
Good features with no real weaknesses
In the test we had the top model with an RRP of 8.499 euros, which has already been reduced to 7.999 euros. The bike comes with the 720 Wh battery as standard, the larger 960 Wh battery costs an additional 200 euros, which is quite fair considering the additional range. There is also a cheaper model, the Bulls Vuca Evo AM1, which costs 1.000 euros less but is less well equipped. The features are quite convincing considering the price and compared to other Pinion E-MTBs. Fox Factory chassis with the beefy 38 at the front, Float It is also worth getting over the fact that the stroke of the support is a bit tight at 4 mm and that the Fox 220 is “only” equipped with the slightly simpler Fit30 cushioning.
frame | Bull's Vuca Evo AM |
suspension fork | Fox 38 Factory Fit4 |
Power Type | Pinion MGU |
Battery | 720Wh (960Wh available) |
Suspension shocks | Fox Float |
Wheels | Ryde Disc 30 |
Tire VR | Maxxis Minion DHF Exo MaxxTerra 2,6" |
Tire HR | Maxxis Minion DHRII Exo MaxxTerra 2,6" |
derailleur | Pinion MGU |
Gear levers | Pinion smart.shift |
Crank | Pinion |
Front derailleur | Without |
Brake | Shimano XT M8120 |
Brake discs | 220 / 203 mm |
Seat post | Limotec Alpha 1 (150mm) |
Saddle | Ergon GE10 |
Stem | Bulls MTBi Sport |
Links | Bull's Enduro Carbon |
The Bulls Vuca Evo AM 2 on the trail
We rode the Bulls Vuca Evo AM 2 extensively on the trails over several days. From the first moment you get on the bike, one thing becomes clear: the Pinion MGU drive unit offers impressive performance and acceleration. It gives the bike the feeling of a real “power engine”. Especially in the higher support levels, the drive unit pushes hard, even at low cadence. However, the volume of the engine varies considerably. In the heavier gears the bike remains almost inaudible, but as soon as you change to one of the lighter gears and increase the cadence, the engine becomes quite loud. This is particularly noticeable in gear 4, which offers a lot of power uphill.
Geometry Bulls Vuca Evo AM
S | M | L | XL | |
---|---|---|---|---|
seat tube (in mm) | 410 | 440 | 480 | 540 |
Top tube horizontal (in mm) | 610 | 620 | 640 | 660 |
head tube (in mm) | 105 | 105 | 120 | 140 |
Steering angle (in °) | 66 | 66 | 66 | 66 |
Seat angle (in °) | 75 | 75 | 75 | 75 |
chainstays (in mm) | 455 | 455 | 455 | 455 |
Bottom bracket drop (in mm) | 30 | 30 | 30 | 30 |
Wheelbase (in mm) | 1216 | 1227 | 1250 | 1273 |
Reach (mm) | 442 | 452 | 472 | 484 |
Stacks (in mm) | 626 | 626 | 640 | 658 |
The seating position of the Bulls Vuca Evo AM 2 is a bit odd. With a flat seat angle and a low front, it feels a bit unusual at first. However, this is hardly noticeable on the trail. Here the Bulls Vuca Evo AM 2 proves to be surprisingly lively, but can also demonstrate impressive taking qualities. The rear end was particularly pleasing and harmonizes well with the front. The higher quality Grip2 damping in the fork would be the icing on the cake.
There is hardly anything to complain about when it comes to the components installed. Depending on the length of your legs, a support with more stroke could be an advantage and if you want to really let it rip downhill, it's better to switch to a tire with a more stable carcass, at least on the rear wheel.
Shifting with the Pinion MGU is great: the gears can be changed in a flash, both on the descent and when stationary or under load; a quick press on the ergonomic shift lever is all it takes. Only two gear changes take a little longer: between gears 4 and 5 and between gears 8 and 9. The reasons for this lie in the internal gear ratio of the Pinion MGU and can be a bit annoying on technically demanding uphills. However, this depends crucially on the individual area of application.
The bike performs well uphill, but when it gets very steep and technical, it requires an experienced pilot: the rear-heavy seating position and the somewhat impetuous starting behavior of the Pinion MGU take some getting used to.