ROTOR 1X13 MTB SUPER LIGHT KIT
With SRAM and Shimano at the top of the chain, these big manufacturers usually produce a new variation of a drivetrain every year. Changes include the latest craze of the 12-speed, adapting technology to create more affordable parts, going to electric actuation or further expanding the drivetrain’s range. Not going to lie, it’s always amusing to watch the big “S” names battle to be every rider’s preferred choice. However much it flip-flops, SRAM and Shimano are now in competition with numerous brands that are seeking different goals within the drivetrain market.
As a few examples, Box Components launched a 9-speed drivetrain with big steps in between gears, yet it still has an 11-50-tooth range cassette. TRP is better known for its brakes, but they, too, are offering some drivetrain options. One being the downhill intended 7-speed, and the other being the 12-speed-compatible derailleur with SRAM’s 10-50 tooth cassette that TRP named TR12 (reviewed in our August 2020 issue). While we have seen SRAM’s AXS 12-speed electric drivetrain win most hearts, Rotor has stepped up by offering a 13-speed hydraulic drivetrain. We were able to connect with the team over at Rotor to send us an Orbea Occam with their complete drivetrain kit for some extended testing time. Let’s shift over to the tech that makes this system unique!
FEATURES AND KITS
Rotor’s 1×13 rear derailleur has the distinctive feature of being universal to their mountain, gravel and road systems. However, some compatibility concerns need to be considered. The 13-speed cassette can only be used on a particular Rotor hub. The HG freehub body splines are the same that they sell on their other hubs, but to fit a 13-speed cassette, Rotor drove the drive-side flange 3mm inboard for a proper fit. So, if you intend to utilize their 13-speed, you will need to have some hoops in mind for a wheel build on top of purchasing the 1×13 kit.
Before we dive into more tech, it is important to note that the 1×13 derailleur can be adjusted easily for use as a 12-speed. If you currently run SRAM’s Eagle cassette, crankset, chainring and 12-speed chain, Rotor says it is compatible. This avoids buying an entire kit if a rider prefers to just purchase the shifter and derailleur. The Shimano 12-speed cassettes, however, use different spacing, so this is not recommended by Rotor.
While 13-speed compatibility is engaging, even more so is the use of hydraulic actuation. So, why did Rotor choose this path? First, they wanted to do something outside the box than the mainstream manufacturers. They determined that an alternative actuation than what was on the market was an excellent way to stick out. Next, they wanted to make their own design choices and not be limited by drivetrain patents. Above all, the 1×13 needed to offer several reliable advantages over the current drivetrain systems on the market.
The design starts with the 1×13’s derailleur that is a sealed shift system to keep dirt, trail debris and water out of the internal workings. Because of this design, there is a once-a-year recommendation to bleed or flush the system. Beyond the beautiful machine work helping protect and seal the derailleur, Rotor also furnished the mechanism with buttons all over. Rather than at the shifter, the only index adjustment is on the derailleur. This fastener can be turned without a tool, but it has a head that accepts a T30. There is also a handy button called “Go to Origin.” By pressing this, the derailleur shifts directly to the smaller sprocket to speed up a rear-wheel change. Rotor went even further to help remove the rear wheel with the use of Quick Extract. This feature allows the top pulley to be pushed out of the way. From there, the rear wheel pops out easily without tension from the chain holding it in place. All these innovative features do come at a cost.
Given that there are few variations to make this system work, Rotor offers individual components while also providing three different kits for the mountain bike. We were able to test the MTB Super Light kit that had Rotor’s Rvolver hubs laced to carbon Enve rims. Here is the kit pricing breakdown and what is included:
1×12 MTB Ready kit:
Includes 1×13 derailleur, shifter and housing, 1×12 cassette (11-36, 11-39, 11-46, or 11-52), KAPIC crankset w/ DM chainring, and a chain.
Claimed weight: 1,531 grams
1×13 MTB Super Light kit:
Includes derailleur, shifter, and housing, 1×13 R/F Rvolver hubs, 1×13 cassette (10-36, 10-39, 10-46, or 10-52), KAPIC Carbon crankset w/ chainring, and a chain.
Claimed weight: 1,816 grams
1×13 MTB Performance kit:
Includes derailleur, shifter and housing, R/F Rvolver hubs, 1×13 cassette, 2INpower crankset/power meter w/ chainring, and a chain.
Claimed weight: 2,082 grams
PERFORMANCE FIELD TEST
Utilizing Rotor’s 1×13 video tutorials, our main test rider took the time to set up the 1×13 system. To begin, we started with bleeding the derailleur given that there were a few other media members that had the bike before we received it for testing. It is quite impressive how the derailleur design can actuate with a minimal amount of oil used. On top of that, there is little heat or pressure on the hydraulic fluid that would typically occur with brakes. This further minimizes the risk of bad shifting performance. Hopping on the bike after setup did take some time with getting used to the shifting ergonomics. At first, some riders might even mistake the single paddle shifter as a dropper post lever.
With some similarities, our test riders felt that it had the characteristics of SRAM’s DoubleTap seen on the road groupset. With a long double push of the lever to actuate up the cassette and a quick tap to move the derailleur down into the higher gears. However, unlike mechanical, the indexing of 1×13 is controlled at the derailleur rather than the shifter. The lever has a less tactile, almost soft, feel than the confirmed click experienced with DoubleTap. Once adapted, the gear transfers feel great in both directions and functions quickly under power to the pedals. While the additional cog is welcome for finding a more refined cadence to the grade being ridden, the almost maintenance-free hydraulic design has some advantages. At the end of the day, we can’t help recognizing the disadvantages it brings as well.
While the 1×13 system has lighter weights on some of its elements than the competition, it’s frustrating to know that the 13-speed cassette is limited to Rotor’s hub design. While the Rvolver hubs are meant to be top of the line, we would have liked to have a higher engagement at their price point. Engagement aside, the hubs perform well and roll smoothly. Perhaps our biggest let down was the chain dropping when we would backpedal. Unfortunately, gearing, spacing, and even some frame geometries can put the 1×13 chain angle out too much to pedal backward. A bit of a pest when spinning the cranks around for take-off and the chain drops in a different gear than selected. We will be honest in saying that the pros are great but we do not feel they warrant changing over. Naturally, if you’re a rider interested in employing something other than Shimano or SRAM, appreciate cutting-edge cycling innovations and owning unique components, then there is little room for discouragement.
• Innovative technology
• The additional cog is great for managing proper cadence
• Lightweight features in comparison to some of the big manufacturers
• Proprietary hubs for use of 13-speed cassettes
• Fast shifting, yet the ergonomics/feel of actuation takes time to adapt to
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