With 13 sprockets alone, the Spaniards will undoubtedly be a talking point at Eurobike. Rotor offers a range from 10 to 52 teeth. But how does that work? After all, the sprockets of Sram's 12-speed cassettes have also moved closer together so that they have room on the already special XD body. Body is also the key word, because Rotor did not develop a wider freehub to be able to fit so many sprockets, but a special hub. The hub flange was shifted more to the left.

The freehub body has the same shape and width as the "old" Shimano hub for their 11-speed cassettes. It "hangs" freely in front of the body so that the small 10-speed sprocket has room.

As Pablo Ortega, Rotor's Global OEM Manager, reveals, the engineers even worked on a 14-speed solution. Although a standard 2x11 drivetrain theoretically has 22 gears, there are actually only 14 because there are always overlaps. However, this was abandoned because the rigidity of the rear wheel could no longer be guaranteed. With 13 gears, however, they are already very close and even offer 520 percent gear coverage compared to Sram with 500 percent and Shimano with 510 percent.

Heartpiece changer

To ensure that the 13 gears can be shifted perfectly, Rotor also supplies the right rear derailleur. It works hydraulically and is the heart of the entire groupset. It is not only used in mountain bikes, but the same changer is also intended for gravel and road bikes. Rotor offers a total of four 13-speed cassettes for this: gradations 10-36 and 10-39 for road and gravel, 10-46 and 10-52 for mountain bikes.

Expensive but versatile

When asked about the price, Ortega is not yet able to give any precise details. The group is currently a well-functioning prototype, but some detailed work still needs to be done on it. Only when this has been completed can the price be worked out. Just this much - the group will certainly be in the upper price segment. But Rotor also offers an alternative solution for those who are interested in the hydraulic system. The changer can be limited to twelve gears and combined with Sram's Eagle cassette. This means you don't need a new cassette or a special hub. Whether the new 12-speed XTR cassettes are also compatible with the derailleur can only be assumed. However, Ortega could not yet confirm this.

It will be some time before the groupset is fully developed, has been tested by athletes and independent testers and is ready for the market. Rotor's 1x13 groupset should then be available in spring 2019.

www.rotorbike.com