2016 is undoubtably the year of plus-size bikes. And we can finally celebrate because those prototypes are out of development and into production! Based on the same frame as the Stereo Hybrid 140 range, CUBE have now launched their first E-MTB with plus-size tyres. Meet the CUBE Stereo Hybrid HPA 500 27.5+. On both our muddy home trails and Barcelona’s dusty, rock-strewn trails, this bike was put under the microscope and expected to perform. So how did it do?
The concept of the CUBE Stereo Hybrid 140 27.5+
The frame on the CUBE Stereo Hybrid 140 27.5+ is pretty much identical to the Stereo Hybrid 140 with conventional 2.35″ tyres, which we’ve already tested and crowned as best value. As its precursor already featured the new wider hubs of the Boost standard, CUBE just had to lengthen the rear end a minor amount to create space for the 2.8″ wide tyres, although they’ve also undertaken a some technical alterations to the main frame for keeping the standover and bottom bracket height the same. Interestingly, CUBE settled on a wholly different spec for this 140 mm travel fully, so we’re curious to see whether it was all wisely chosen.
The spec of the CUBE Stereo Hybrid 140 27.5+
The suspension takes its roll-call from two of the industry’s top players, seeing a RockShox PIKE RC with the shiny new Boost hub width at the front and a FOX rear shock. As the PIKE RC already features one pre-installed air volume spacer, they’ve got that desirable smooth progressivity yet still sitting high in travel – despite the heavier weight that comes from being an E-MTB. As a result, you won’t catch us bemoaning the absence of the RCT3’s three distinct modes. At the rear, there’s a super responsive FOX FLOAT DPS rear shock with an EVOL air chamber, which delivers great responsiveness at the start of the travel and offers more mid-stroke support. It also features the valuable CTD switch, which you’ll hold in high esteem as the sensitive rear end still generates great traction even in the stiffer Trail mode.
Fork: Rock Shox Pike RC Solo Air 140mm
Shock: FOX Float DPS Performance
Motor: Bosch Performance CX
Battery: Bosch Power Pack 500
Brakes: Shimano MT5 180/180
Drivetrain: Shimano XT
Seatpost: RockShox Reverb Stealth
Stem: RaceFace Turbine
Handlebar: RaceFace Evolve 750mm
Tyres: Schwalbe Nobby Nic Kevlar 2.8 Trailstar/ PaceStar
Wheels: DT CSW B+ 3.7 Straightpull Wheelset
Weight/Size: 22.1 kg / Size 18″
Price: € 4,799
The Race Face cockpit with its 750 mm wide bars and short 50 mm stem are so tuned to the CUBE’s purpose; not too wide for long rides, they still offer sufficient control for gnarly and steep sections. Of course, a dropper post is now compulsory on such bikes (as you may have heard us proclaim), and the RockShox Reverb Stealth on the Stereo Hybrid is a great choice.
We normally wouldn’t recommend anything less than 200 mm front disc brakes for an E-MTB, but the precise dosability and stability of the MAGURA MT5 brakes is just so high that both of its 180 mm discs are more than sufficient for regular use. Perhaps that explains why they won our group test so decisively then. However, if you are firing up for long, steep downhills in the Alps (or you’re a heavier-built rider) then we’d recommend something sturdier purely based on their performance at dissipating heat and keeping consistent.
The DT Swiss wheelset is made of high-quality stuff as you’d expect, and the 40 mm rim widths are spot on for the 2.8″-wide Schwalbe Nobby Nic tyres. However, the 6 bolt rotos sits on the centerlock hub with an adaptor – a setup that we’ve encountered issues with on other bikes, seeing the lockring loosen or lead to noise. The 6 bolt standard would have been a better choice, but DT Swiss, unfortunately, don’t do this version.
Shimano’s XT drivetrain is quintessentially flawless, quiet and quick, with the 11-speed shifters giving a satisfying click through the gears.
You can’t waste any words complaining about the Bosch CX motor as it represents the pinnacle of motor design at the moment. With a 500 Wh battery coming as standard, you’re unlikely to get caught out on long rides.
How it rides
On climbs, the CUBE Stereo Hybrid 140 27.5+ has the ground in a death grip thanks to its tyres and plush suspension. Add in the powerful CX motor and the bike becomes a veritable climbing machine on virtually every type of terrain.
But even on descents the CUBE knows exactly what gets us going, and its balanced geometry with the simply spot-on 67° head angle means that we’re in our element on flat as well as steep trails. Given the wide tyres and therefore slightly longer chainstays, it admittedly isn’t as agile as its regular-tyred brother, but it’s still a long way from sluggish and can still weave a tidy line around tight turns.
So good you barely notice them, the RockShox PIKE forks know exactly the right amount of travel and when. At the rear, the FOX DPS rear shock gives a buttery feel to travel thanks to the EVOL air chamber, and it nails the responsiveness to big hits and minor trail chatter alike. Adding the Stereo’s rear character, which is more towards the linear end of the spectrum, it sits quite a bit in travel but also keeps there firm and stable. However, we’d recommend riding the CUBE with slightly less SAG than usual – 20% proved optimal during our testing.
The CUBE Stereo Hybrid 140 27.5+ has a really stable handling packing, and the top-end performance and braking power of the MAGURA MT5 brakes guarantee a ride where you’re conscious of the control and confidence at all times. The chubby tyres and plush suspension are so well complemented, working together to iron the ground flat and generate nigh on unrivalled grip whatever the terrain – the drier and rockier, the better, and they’re not adverse to root gardens either. Yet the tyres keep so firmly planted that drifting around loose corners becomes a task in itself. Our 76 kg rider determined that 1 bar air pressure was ideal. Thanks to the well-made DT Swiss rims, the conversion to tubeless can happen without any undue hassle – plus, it’s virtually mandatory for any (e-)mountain bike these days given the improved puncture resistance.
However, as our home trails witnessed – plus-size tyres have their drawbacks. When it’s wet the width of the tyres mean that they struggle to cut through the mud and find traction, leaving you feeling somewhat like you’re swimming, so ride accordingly. But this drawback doesn’t apply exclusively to the CUBE and is part-and-parcel of the on-going development of plus-size tyres. We’re confident that tyre manufacturers are already well into development when it comes to refining an adequate profile and creating a solution to improve these types of situations.
Geometry of the CUBE Stereo Hybrid 140 27.5+
| Size | 16″ | 18″ | 20″ | 22″ |
|---|---|---|---|---|
| Head Tube Angle | 67,3° | 67,3° | 67,3° | 67,3° |
| Seat Tube Angle | 74° | 74° | 74° | 74° |
| Top Tube | 570 mm | 590 mm | 608 mm | 619 mm |
| Head Tube Length | 110 mm | 120 mm | 130 mm | 150 mm |
| Seat Tube Length | 380 mm | 420 mm | 470 mm | 520 mm |
| BB Drop | -15,5 mm | -15,5 mm | -15,5 mm | -15,5 mm |
| Chain Stay Length | 476,5 mm | 476,5 mm | 476,5 mm | 476,5 mm |
| Wheelbase | 1158 mm | 1179 mm | 1198 mm | 1211 mm |
| Stack | 589 mm | 589 mm | 608 mm | 626 mm |
| Reach | 402 mm | 419 mm | 435 mm | 440 mm |
Conclusion
We love it! The CUBE Stereo Hybrid 140 HPA 500 27.5+ delivers a top-notch combination of value for money and an outstanding performance on the trails. The spec has been chosen wisely, and the bike is forgiving, exciting and stable without being sluggish or tame thanks to the plus-size tyres and great balanced geometry. You’ve got to make allowances for how it rides in deep mud, but the traction won’t give any rise for complaint on any other surfaces. And who can argue with the price tag of € 4,800 for such a winning bike, which just works.
More information on the Cube website
Words: Andreas Maschke Photo: Christoph Bayer, Klaus Kneist
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