E-mountain bikes: Test: BH Atom Lynx 4.8 27,5 E-MTB – powerful tourer or sporty trail bike?

Test: With the BH Atom Lynx 4.8 27,5, the Spanish manufacturer BH is presenting a new E-MTB with a Brose motor that, with its 120 mm spring travel front and rear and a sporty geometry, is somewhere between a powerful tourer and a playful trail bike. We subjected the new e-fully to a tough test on Mallorca.

BH Atom Lynx 4.8 27,5: frame and geometry

The BH Atom Lynx 4.8 has a non-electric namesake in the Basque range who was the inspiration for the development of the Atom Lynx 4.8: The Lynx platform has been around for around three years now and the Lynx 4.8 in particular is the trail bike of BRA. So that shows very clearly where the Atom Lynx 4.8 is headed – with 120mm travel, 27,5″ wheels, the Split Pivot rear triangle and modern geometry, the new Brose Fully is more of a trail robber than a relaxed tourer.

E-MTBs present designers with new challenges in terms of geometry. This is mainly due to the rather long chainstays due to the mid-engine, which allow the wheelbase to grow overall. Although this is good for smooth running, it costs a few percentage points in terms of agility compared to non-motorized mountain bikes. For this reason, BH could not adopt the geometry of the "Ur-Lynx" 1:1; However, looking at the geometry tables, it becomes clear that they have oriented themselves to their own, established trail bike. The pleasantly flat 67° steering angle increases smoothness and reduces possible rollover feelings, the long reach pushes the rider into an aggressive position on the bike even with a short stem. At 466mm, the chainstays are also pleasantly short for an E-MTB. We think it's a bit of a shame that the BH Atom Lynx 4.8 will initially only be available in two frame sizes, medium and large.

In addition to the geometry, it is of course the rear end that decides whether you are frustrated or having fun on the trail. Even if this differs fundamentally from the non-E Lynx at first glance, both rely on the same concept: Split Pivot. This is a kinematic system developed by rear end expert Dave Weagle, which allows detailed fine-tuning of the individual drive influences via a clever arrangement of the bearing points. For example, the damper and rear triangle remain active even if the rear wheel locks up.

Thanks to the battery integrated in the down tube (more on that in a moment), the slim motor and the pleasing lines, the BH Atom Lynx 4.8 cannot be identified as an E-MTB at first glance. Cables and cables run inside the frame of the main frame and are kept under tension with screwable rubber grommets so that there is no unpleasant rattling inside the frame, even on rough terrain.

BH Atom Lynx 4.8 27,5: drivetrain and engine

Now we come to the heart of the BH Atom Lynx 4.8 - the engine. At BH, the suffix Atom stands for e-bikes with drive from the German manufacturer Brose - so here too. The drive has been established on the market for a few years now, but is getting an exciting software update for 2017, which is intended to eliminate some of the criticisms of the past. Not only was it possible to optimize the range, but the peak power also increased by around 6%. There is now also an additional support level - a total of four - to choose from; BH is the first manufacturer to offer an E-MTB with this new feature.

We find the battery hidden in the down tube almost more interesting than the new drive. It is an in-house development by BH with 600Wh. The increased capacity could be achieved by using a new battery cover, which is no longer made of plastic as before, but of aluminum. This made it possible to reduce the material thickness with the same stability - this creates more space inside for more energy cells and an overall higher capacity. The change of material has another positive side effect, namely significantly improved heat dissipation.

If desired, the battery can also be easily removed and charged outside of the bike. Thanks to the charging port integrated in the down tube, charging when mounted is no problem, for example in the garage at home.

Another innovation is hidden on the handlebars: the display and control unit have been given a comprehensive facelift by the Spanish manufacturer. The new display has similar dimensions to its predecessor, but the display area itself is now significantly larger thanks to the thinner bezel. The integrated USB port can now also be used to conveniently charge or supply power to smartphones or other devices while driving. Thanks to the exposed position above the stem, the data can be read easily, but the display is quite unprotected in the event of a fall. With the large buttons and the robust workmanship, the control unit is very well suited to the area of ​​application on the MTB.

BH Atom Lynx 4.8 27,5: Features

Frame: check. Drive: Check. But what about the other equipment on the BH Atom Lynx 4.8? As with the recently introduced BH Rebel Lynx 5.5, the Atom Lynx will only be available in one configuration for the time being. When it comes to the chassis, you rely on full Fox power and pair the Fox Float DPS Performance damper with the FOX 34 Float Rythm fork with 120mm. The Rythm fork is new this season and, apart from the slightly simpler damping, corresponds to the performance version. Thanks to the 34mm stanchions, it is stable enough for rough trails and the slightly higher weight of an E-MTB. The Float DPS damper comes with an adjustable compression stage, which the driver can set between open, medium and hard using a thumb lever.

The BH Atom Lynx 4.8 shifts using a Shimano XT / SLX combination. The 11-speed XT rear derailleur lets the chain slide from sprocket to sprocket on the SLX cassette. The latter has a wide range of 11-42 and should – especially on e-bikes – offer more than enough range. The brakes also come from Shimano; the SLX stoppers are paired with 180mm discs front and rear and should have more than enough power in the pistons for a bike in the class of the Atom Lynx.

The wheels consist of unspecified rims on JoyTech hubs. The tires used in the series are Schwalbe's Tough Tom with a width of 2,35″. If the name Tough Tom doesn't mean anything to you: This is the "old" Nobby Nic before he received a new profile for last season. Due to the difficult trails and the demanding surface, the combination of Hans Dampf and Magic Marry was installed on our test bikes in Mallorca.

The seat post is once again an issue in itself: In the production version, the BH Atom Lynx 4.8 comes with a normal 31.6 aluminum seat post. In difficult terrain, however, some riders will certainly want a retractable dropper post - here, as with many of its models, BH offers a so-called trail kit. For €369 you not only get a Kindshock LEV DX dropper post, but also much more powerful tires with the Michelin Wild Grip'R.

BH Atom Lynx 4.8 27,5: Driving impressions from the trail

But now enough with the gray theory, because the truth is, as so often, on the trail. In our case on the rocky ground of the sunny island of Mallorca, where we were able to put the BH Atom Lynx 4.8 through its paces as part of a press camp. The trails of the Mediterranean island are demanding terrain and we were quite curious to see how a trail bike like the Atom Lynx, which is not designed for super-heavy terrain on paper, would do here. From the start towards the trail, we first had the opportunity to test the Brose motor, or rather the new software.

The additional top performance is definitely noticeable - in the highest support level Boost, the still whisper-quiet Brose drive delivers significantly more power than we have been used to from the German drive. However, it does not lose any of its strengths: the support is still very homogeneous and still feels natural even at the highest level. The new display is very easy to read, offers sufficient information and the control lever is easily accessible even in the heat of the moment. Thumbs up, a lot has been done right here.

After a short drive, we started on the first trail. First impression of the rear triangle: is it really only 120mm? Definitely feels like more and makes the Atom Lynx an amazingly capable bike. The difficult, rocky and partly blocked terrain on Mallorca was an endurance test for a bike in this class. Time and time again we were rudely reminded that we'd rather have a light trail bike than an enduro machine under our butts; the Lynx was a bit too front-heavy for us on steep steps. On the other hand, the new BH E offspring really blossomed on flowing trails. The quiet yet powerful engine, the potent, comfortable chassis and the homogeneous equipment really put you in a good mood.

However, we did find a hair in the soup: The handlebars are simply too narrow at 720mm. Even leisurely touring riders should appreciate the added control of wider handlebars. In an emergency, this could be shortened anyway. The handles weren't quite to our liking either. Although they offer decent grip, they are quite thin and lack any cushioning.