Rotwild C+ HT 29 PRO
Rotwild’s C+ PRO hard tail electric mountain bike makes no compromises, it’s fitted with the very best gears, brakes, suspension and dropper seat post. The core of the C+ EVO is Rotwild’s patented aluminium-carbon composite monocoque frame which keeps weight as low as possible while not compromising strength. The result is a lightweight and agile e-mountain bike built for endurance and with real cross country character. When switched off or at speeds over 27.5kmh the 90 Nm BROSE e-bike drive system is disengaged completely so does not cause any pedaling resistance. The compact design of the drive system and IPU make it easy to mount a bottle cage and double derailleur. A 234Wh range extender can also be fitted. Its balanced frame geometry with 29″ wheels and 69 deg head tube angle provides a sporty compact, integrated seating position, rolls well over terrain and offers a high level of safety while reducing lip-over sensation on steep descents.
The Rotwild C+PRO is stronger – its uni-directional Carbon Fiber / 6066 T6 Alloy monocoque frame make for the most rigid e-bike frame in the world.
The most distinctive feature of the new Rotwild hybrid mountain bike is the Integrated Power Unit (IPU). This part of the bike combines the magnesium motor casing with the carbon composite battery pack to form a rigid structural element, connecting bottom bracket to head stock like they’ve never been connected before. This state-of-the-art engineering never usually gets beyond the perimeter fence of a McLaren or Williams Formula One R&D center. It makes the Rotwild the stiffest electric mountain bike in the world; it won’t twist, buckle, or bend no matter how hard you’re riding it, no matter high you’re jumping it. Unbeatable.
Rotwilds are lighter – the C+PRO weighs in at just 17.8kg, 14% less than its nearest rival.
Despite having lower power batteries, the C+’s nearest rivals are much heavier: The Moustache 29er is 20.1kg, the Haibike Bosch XD HardNine Carbon Pro 21.0Kg, and the Haibike Yamaha SD HardNine weighs in at 21.1kg.
How have Rotwild achieved this feat? The secret is in engineering nous and use of the very latest materials and production technology: The IPU bottom tube battery housing is built up using multiple uni-directional pre-impregnated carbon fiber layers of precisely defined weights, each carefully orientated to follow the load-paths generated from the hardest riding. Thickness of the carbon bottom tube is varied throughout its section – not to thin, not too thick – but just the right number of layers to achieve the maximum possible rigidity and lowest possible weight.
The IPU is formed and bonded to other fame components using the high-precision ‘closed-mold’ process (other frame makers use inferior ‘open-mold’ or ‘vac-bag’ processes). This requires over 70 individual molds to make Rotwild’s three carbon/aluminium frame types. It works: these material and process choices have delivered successes on the toughest race courses, and demonstrated clear performance advantages at the pinnacle of international competitions. Trophies galore at the Olympics Games and victory in the XC World Championships attest to the capabilities of Rotwild bikes.
Aluminium elements of the frame are equally exceptional; formed from 6066 alloy heat treated to Condition T6, this aluminum alloy is stronger and lighter than the standard 7020 T6 used by most MTB makers. It’s improved characteristics are significantly higher tensile strength (around 30 %), and much greater resistance against bending, compression, and shear loads (around 40 % greater).
In short, if you choose a Rotwild C+ you won’t be sending your frame back to us in five years riddled with fatigue fractures, but even if you did, it’d be 14% cheaper to post than any other electric mountain bike!
The Rotwild C+ is more powerful – with a whopping 90Nm on tap it has a 20% power advantage over its nearest rival.
The beating heart of a Rotwild is the peerless BROSE 2.0 Drive Unit. For 2016 the Brose has new software giving more low-speed torque and smoother power delivery across all speed ranges. Its main ingredients are aluminum, magnesium, experience, enthusiasm and …helical epicyclic gears! Designed in Germany, its made there too.
Where other well known e-bike motors are built to a price point, the Brose 2.0 is designed and manufactured to a quality standard, incorporating precision engineered helical epicyclic gears. These are much more expensive to manufacture but offer dramatic performance and wear rate improvements over the cheaper spur gear tooth profiles that the completion use.
In the simplest terms spur gears transfer power from the driving gear to the driven gear via only one or two teeth at a time, whereas with helical gears power is transferred by three connecting teeth at a time. This results in less wear, less noise, less friction and a smaller and lighter drive unit.
Rotwild’s main rivals use either a Yamaha or Bosch motor – these are not only heavier and bulkier than the BROSE motor – for example on the Bosch unit there’s no space for a 2nd chainwheel – but they are also considerably weaker: Torque for Bosch CX unit is 75Nm and for the Bosch Performance motor its only 60Nm. The table below show the impact this has on all-important Power to Weight Ratios – The C+’s Power to Weight ratio is 40% higher than its closest rival.
How do they compare?
|Haibike Bosch Hard Nine Carbon Pro
|Weight:||18 Kg||21 Kg|
|Power to Weight Ratio:||5 Nm/Kg||3 Nm/Kg|
|Battery Capacity:||518 Watt Hours||500 Watt Hours|
|Charge Time:||50% 1 Hr, 100% 2.5 Hrs||50% 2 Hrs, 100% 4.5 Hrs|
|Price:||£ 3’999||£ 4’766 (est. based on EU SRP & UK markup )|
Weights estimated based on 2015 MY. 2016 MY weights to be confirmed.
Despite its small physical size the BROSE 2.0 produces a market leading 90 newton meters of torque. It does this quietly, reliably and without fuss. The company’s sensor concept is the only one of its kind on the market today: it measures rider pedal force no fewer than 420 times a second, delivering smooth, vibration free assistance. Production began in July 2014 and by August this year the Rotwild/Brose test team had covered 69’445 miles of arduous Alpine trails.
Brose Drive Technology is a division of the Brose Group, one of the most innovative and successful suppliers to the international automotive industry, employing some 22,000 employees – 2,500 of them engineers – at 57 locations in 23 countries around the world. Their annual turnover exceeds €5 billion. Last year Brose manufactured 100 million electric motors. They know what they’re doing.
Decades of experience specialising in mechatronic systems for the automotive sector mean they’re perfectly placed to produce this innovative e-bike drive unit. Development and production of the Brose e-bike motor is carried out entirely in-house at their Berlin engine plant, where a dedicated team of engineers design, build and test the system at their purpose built e-bike center of excellence .
The Rotwild C+ goes further than the rest – at least 30% further than its nearest rival.
The Li-Ion battery is integrated into the carbon fibre bottom tube, ensuring the lowest possible centre of gravity, and at 518Wh the battery will drive you further than other electric MTB in it’s class. It’s not just me! Many of our Rotwild customers have had first hand experience of the Brose’s efficiency – of course the range between re-charges on a Rotwild is greater than any of its competitors because it has a higher capacity battery, but that does not explain how a Rotwild with 20% more power than its rivals can run flat out at Cannock Chase from 11am to 6pm, stopping only for a coffee in the morning and a single pint in the afternoon on one charge. Clearly, most of the range advantage is down to the efficiency of the Brose drive unit.
MTB ledgend Richie Schley shows how to do it on a ROTWILD:
We visited Rotwild’s design and production center in Frankfurt where the team showed off the cutting-edge design manufacturing processes behind the range of Rotwild electric mountain bikes. Here are some photos we took, for full size images please click this About Rotwild link.
- IPU – Integrated Power Unit with ROTWILD Power Pack and Brose Power Engine
- Carbon-Downtube with integrated battery
- CHANNEL Hydroforming XC Tubeshape
- RHS 15 – Integrated stainless steel headset 1.5“ / Tapered / Ti Coating
- Brake post mount 180mm
- Exchangeable drop out inlays MDI2 / Direct Mount
|HEADSET||ROTWILD RHS 15 TI|
|FORK||FOX 32 FLOAT 100 FIT4 PERFORMANCE|
|BAR||CRANKBROTHERS COBALT 11 740MM|
|SEAT POST||KIND SHOCK LEV INTEGRA Ø27.2 REMOTE 100|
|SEAT||ERGON SME30 RW|
|DRIVE UNIT||BROSE 2.0|
|BATTERY||ROTWILD POWER PACK 518Wh|
|CRANK||E13 TRS+ ISIS DOUBLE 38-24T.|
|SHIFTER||SHIMANO XT I-SPEC II|
|FRONT DERAILLEUR||SHIMANO XT-2|
|REAR DERAILLEUR||SHIMANO XT-10 GS DM PLUS|
|CASSETTE||SHIMANO HG81 11-36T.|
|BRAKE||SHIMANO XT FIN PAD|
|ROTOR||SHIMANO RT81 ICE 180/180|
|WHEELSET||DT SWISS M1900 SPLINE 15/12 RWS|
|TIRE||CONTINENTAL X-KING RACESPORT 29×2.40|
Specifications correct at product launch date and may vary during production year.
|A||SEAT TUBE LENGTH||(mm)||440||470||500||540|
|B||TOP TUBE LENGTH||(mm)||575||590||620||645|
|C||HEAD TUBE LENGTH||(mm)||125||125||130||140|
|D||CHAIN STAY LENGTH||(mm)||455||455||455||455|
|F||HEAD TUBE ANGLE||( ° )||68.75||69,0||69,25||69,5|
|G||SEAT TUBE ANGLE||( ° )||74.0||74,0||73,75||73,5|
Here are some videos ROTWILD have produced to show how their electric bike technology works, and how it beats the competition:
Here are some videos showing the partnership between Mercedes-AMG and ROTWILD:
And finally, here are some of the clever folk that make and ride ROTWILD MTBs:
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