Bytager the publication "12 or 13 speeds, which choice for your transmission?"
In the world of cycling on route and gravel, where precision and efficiency are paramount, the transition from an 11-speed drivetrain to a 12- or even 13-speed drivetrain still fuels technical debate. For an experienced cyclist, changing drivetrains is not just a cosmetic upgrade: it requires a detailed analysis of the proposed developments, mechanical compatibility, and the impacts on the entire system.
By Guillaume Judas – Photos: depositphotos.com, ©SRAM, ©Campagnolo, ©Cervélo, ©Specialized, ©3bikes
For over 40 years, the evolution of the number of gears, from 5-sprocket freewheels to modern cassettes, has transformed cycling on route, mountain biking, cyclo-cross and now gravel. While each new standard has met with initial reluctance due to mechanical constraints, riders generally come to appreciate the comfort offered by additional sprockets.. With the arrival of 12-speed transmissions in the early 2020s, followed by 13-speeds, It is even the concept of the double chainring that is being questioned, potentially marking a revolution.
The challenges of switching to 12 or 13 speeds
Moving from an 11-speed drivetrain to a 12 or 13-speed involves thinking about your gear range needs.. Adding one or two sprockets to the cassette allows manufacturers to expand the gear range, providing more versatility. Whether you're a professional racer or a touring cyclist, a 12-speed cassette typically increases the gear range by 10 to 15 percent compared to an 11-speed, making changing cassettes unnecessary for varied rides except in special cases. With 13-speed, this range expands further, but thetagement is not necessarily finer, contrary to what one might expect.
Concretely, New cassettes prioritize versatility : small sprockets (10 or 11 teeth, with atagement "tooth by tooth" up to 13 or 15) for riding fast on the flat or downhill, and large sprockets for climbing steep slopes. However, to maintain a smooth pedaling cadence around 30 km/h, these very versatile cassettes sometimes have marked gaps between sprockets (for example, from 15 to 17, 16 to 18, or 17 to 19). This "jump" can bother some cyclists, who regret the absence of cassettes with a narrower range, better suited to specific routes.
This is why some people are hesitant to adopt these new transmissions: What's the point of more sprockets if the teeth offered don't always match their usual needs?
Ever more efficient transmissions
The 12 and 13 speed transmissions, however, offer advantagestagundeniable, especially in terms of speed, fluidity and precision of gear changes, which improve with each generation, especially with the widespread use of electronic derailleurs. These systems, present on almost all 12- and 13-speed drivetrains (with a few exceptions, such as some entry-level mechanical options), allow for customization via dedicated applications. Thus, upgrading to a new generation is not just about gaining one or two sprockets, but about benefiting from an overall more efficient groupset.
However, this gain has a cost. Transitioning to 12 or 13 speeds often requires replacing the entire groupset (levers, crankset, derailleurs, cassette, chain), for a budget of €1,500 to €4,000 depending on the range. Some drawbacks also persist. In 12 speeds, cassettes with a wide development range require a longer derailleur cage, adding 20 to 30 g. The total weight of the groupset increases slightly (+50 g for a 12 speed cassette compared to 11). With 13 speeds, the narrowness of the sprockets (reduced spacing) increases the tension of the derailleur springs, which can accelerate chain wear.
Additionally, wheel compatibility remains limited, especially for proprietary standards like Campagnolo's N3W. Finally, for users of 11-speed mechanical groupsets, upgrading to a high-end 12-speed often requires an electronic derailleur, with the constraint of regular battery charging.
13 speeds and the single chainring question
With a double chainring, some ratios overlap, so that a 2x11 or 2x12 transmission actually offers only 14 to 15 distinct ratios. In view of this, Manufacturers are developing single-chainring transmissions with 12 or 13 rear sprockets, offering almost as many available ratios as a double chainring, but with more simplicity, weight savings and better aerodynamics. This choice is particularly popular in mountain biking and gravel, where the absence of a front derailleur reduces mud accumulation, but it is also gaining ground on the route.
However, a single-chainring transmission involves more marked gaps between each sprocket, especially with cassettes with a wide gear range (e.g., 10-51 teeth on gravel). For use on hilly but not very steep courses (such as in the north of France), a single chainring can be ideal, provided you can adapt the cassette for more demanding terrain if necessary.
At SRAM, for example, 12-speed single-chainring drivetrains route are compatible with cassettes from 10-28 to 10-36. With a 50-tooth chainring and a 10-28 cassette, the smallest gear ratio is equivalent to a 39/22, sufficient for 99% of our outings on the plains (Paris region, Picardy, Bretagno). In mytag10-30, 10-33 or 10-36 cassettes offer gear ratios equivalent to 39/24, 39/26 or 39/28. SRAM also offers smaller chainrings (48, 46, 44, 42, 40, 38 teeth) to accommodate those who find the 50 too "strong".
With 13 speeds, the single-chainring option becomes even more attractive. At SRAM, XPLR gravel groups offer a wide range of gears. Campagnolo, pioneer of 2×13 on route with the Super Record Wireless, offers an interesting single-deck alternative with 10-29 or 11-32 cassettes, providing atagbalanced. It remains to be seen whether Shimano, with the future Dura-Ace Di2 (the current one dating from 2021), will follow this trend or offer another approach.
Wheel compatibility: a key constraint
The change to 12 or 13 speeds directly impacts the choice of wheels via the compatibility of the freewheel bodies. Sprocket spacing is decreasing (3,7 mm for 11-speed, 3,3 mm for 12-speed, even less for 13-speed). Shimano and Campagnolo offer partial backward compatibility for 12-speed: a Shimano 12-speed cassette can be installed on an HG 11-speed body, thanks to similar spacing on the first sprockets (although the derailleur must be compatible). This allows you to keep your existing wheels.
On the other hand, SRAM imposes the XDR standard for its 12-speed AXS groupsets, incompatible with the HG due to an additional height of 1,85 mm. For 13-speeds, as with the Campagnolo Super Record Wireless, the N3W body (11/12/13-speed compatible) is required, limiting the wheel options. For gravel, Shimano's Micro Spline standard for 12-speeds (10-tooth starting cassettes) is also specific.
For an experienced cyclist, It is crucial to assess the compatibility of your wheels, especially if they are used on several bikes or a home trainer. Shimano remains for the moment the most flexible option to avoid hub changes.
A strategic choice for the experienced cyclist
The choice between 12 and 13 speeds depends on your practice. The 12 speed is now an established standard on route at Shimano and SRAM, offering a good balance between versatility and precision. The 13-speed is essential in gravel with single chainrings (SRAM XPLR, Campagnolo) and is slowly making inroads on route with the Campagnolo Super Record Wireless 2×13, before a possible generalization in the years to come.
In both cases and if you are still hesitant, the gains in étagPrecision and precision win out if you invest in the right wheels, but compatibility and cost constraints put a brake on impulsive upgrades. Consult a mechanic for a montage personalized – The ideal transmission is one that fades into the background in favor of your power..
