The Cube Nutrail Hybrid
We faced two challenges in designing the Nutrail Hybrid. On the one hand, we set out to build a superb fatbike that would be fun to ride, whether that’s on an everyday basis or on longer back country adventures. And on the other, we needed to perfectly integrate the Bosch drive, with all its specific requirements, into a frame designed around 4 inch tyres. It wasn’t easy, but we got there the usual CUBE way: by sweating the details. Triple butting, hydroforming and clever design all contribute to a frame that’s extremely light, with precision handilng to match. The tapered head tube and 177m rear through axle provide even more rigidity. We positioned the drive and battery for optimum performance and this, combined with our Agile Ride Geometry (ARG) guarantees faultless, intuitive handling. Luggage rack mounting points give the Nutrail extra practicality for day-to-day use. And, of course, we routed cables internally for smooth shifting and clean looks.
Cube Nutrail Hybrid Features
This steerer tube design is stiffer than a conventional straight steerer and yields a more secure ride feel even in difficult terrain. Minimal flex at the front of the frame means the greatest possible steering precision. With the larger steerer, the forks become more rigid. At the same time weight is saved due to the absence of bearing shells as the lower bearing is fully integrated into the head tube. On all of our CUBE carbon models the upper bearing shells are also directly in the frame, so that once more a few grams are saved and the energy transfer is very direct.
Agile Ride Geometry
We ran innumerable tests to develop the Agile Ride Geometry in our series of big wheel bikes. We also added the 27.5in wheel size to the very well received portfolio. Three important details lead to the very agile character. Increased fork offsets let us achieve the same trail as our 26in bikes without having to steepen the head angle, thus maintaining generous toe clearance to the front wheel. Secondly we shortened the chain stays without compromising the seat angle. We invented a patented construction to mount the front derailleur to give us more tyre clearance while keeping a conventional seat angle, leading to a perfect riding position for every rider size. Last but not least we kept the BB height the same as on our 26in bikes.
Optimal Drive Position
The engine is the critical part of an Ebike because of its weight and its junction to the regular drivetrain. These factors present a real challenge for the frame design. This is why CUBE developed an innovative new frame construction for the new Ebike generation: simultaneously being the cradle for the electric motor, the pivot for the rear link and the seat of the shock eyelet, the very complex area of the bottom bracket is made of two forged halves. The groove in the front section together with the specially formed down tube is home for the power pack which in this way has a very low position in the frame triangle. The positive outcome is an extremely low center of gravity supporting an agile riding characteristic while achieving a super rigid bottom bracket area.
The Cube Nutrail Hybrid models are built using Advanced Hydroforming. Conventional hydroforming processes cannot achieve these custom shapes and technical advantages. As this manufacturing method reduces the number of welds, the weight is reduced while durability is increased.
Frame Safe System
To protect our high-end aluminium frames from damage, they are built with the CUBE Frame Save System replaceable derailleur hanger. The mounting thread is in the hanger and not in the frame as usual. In case of a crash, this hanger can be easily and quickly replaced by a new one.
Easy Mount Kickstand
The Easy Mount Kick Stand is a new system developed and designed by CUBE. The base of the stand is mounted from below to a fitting plate integrated to the frame and fixed with a through bolt. This kick stand is extremely stiff and solid through the enlarged contact areas between base and frame which gives a stable stand even with loaded panniers.