The sparrows were already whistling it from the rooftops: Shimano representatives already held out the prospect of the CUES concept being extended to road and gravel bikes when it was launched in 2023. In the summer of last year, there was growing evidencethat the 2025 model year will herald a new era for particularly affordable road and gravel bikes. The curtain has now been lifted: specific components such as levers for racing handlebars and cranks with entry-level road bike gradations are being introduced. The CUES components will characterise the road bike market in the lower price range in the future.
Traditionally, Shimano has almost a monopoly when it comes to affordable bikes; the competition from SRAM and Campagnolo comes in at a much higher price. The components were developed with beginners in mind; they should be particularly simple, low-maintenance and durable. The available gear ratios are also primarily aimed at lower performance levels. However, one aim is also to make it much easier to find wear and spare parts in the future. It is often confusing as to which components are compatible with each other when it comes to gears and brakes. The inexpensive Tiagra (ten-speed), Sora (nine-speed) and Claris (eight-speed) road bike groupsets will be cancelled without replacement with the introduction of CUES.
Shimano CUES: Modular for different applications
The concept sounds obvious and simple at first: the Shimano CUES components can be combined modularly with different drivetrains in nine-, ten- or eleven-speed configurations; there are also cranks in two quality levels, with one or two chainrings and in various gradations. In this way, CUES serves different price ranges, bike types and performance levels, but uses many identical parts. Brakes, derailleurs, cranks and chains, for example, are interchangeable, and all drivetrains run on Shimano's eleven-speed chains. Even the gear levers can control several drivetrain configurations: the right-hand gear lever can operate nine, ten or eleven sprockets; the levers for mechanical disc brakes are at least nine- and ten-speed compatible.
No longer a "spare parts supplier" for older racing bikes
In reality, however, the introduction of CUES is likely to pose new problems for cyclists within the Shimano world. Because the sprocket spacing and widths are standardised for all cassettes from nine to eleven sprockets in the CUES environment and are based on the new, more durable Linkglide tooth profile, the parts are no longer compatible with other road bike groupsets with the same number of sprockets, or only to a very limited extent. Until now, orientation was easier here: Everything with the same number of sprockets generally fitted together, regardless of the generation.
The CUES parts alone are therefore not suitable as a "spare parts supplier" for older, high-quality groupsets with nine or ten sprockets. In any case, the Shimano CUES cassettes, usually the most interesting wear parts, with at least 36 (nine-speed) or 39 teeth (ten-speed) are not suitable for road bike drivetrains, as the large sprockets cannot be handled by the older rear derailleurs. The double cranks, like the GRX gravel groupset, also have a chain line that is 2.5 millimetres further out, which allows for wider tyres. In turn, the CUES derailleur is adapted to this.
Compatibility within the CUES switching group
But even in the Shimano CUES environment there are, at least according to the press release, rather confusing compatibility restrictions. For example, only nine- or ten-speed cassettes are possible with a double crank, as the eleven-speed cassettes are only available in correspondingly large dimensions for single drivetrains (45 or 50 teeth). The levers for hydraulic brakes will not be able to shift nine-speed systems and those for mechanical disc brakes will not be able to shift eleven-speed drivetrains.
Also, mechanical disc brakes cannot be combined with double cranks, as there is no corresponding left-hand brake lever. There are no matching mechanical brake callipers, so you have to make use of other groupsets. The modular platform is therefore not entirely consistent, which is probably partly due to the respective needs of the target groups.
The CUES therefore remains a separate, self-contained world for future gravel bikes and, if they still exist in the future, very affordable road racing bikes. You can see from the portfolio that Shimano hardly gives the latter any chance: In terms of gear ratios, the CUES is focussed on gravel and all-road use, with the exception of the compact crankset with 50/34, there is no classic road bike gradation. In response to our enquiry, Shimano confirmed that the pure road bike groupsets Sora (nine-speed) and Tiagra (ten-speed) will be completely discontinued. With the introduction of the CUES, many inexpensive mountain bike groupsets have already been cancelled.
The new Shimano CUES components
Gear lever and brake lever
Shimano Cues ST-U6030
- For hydraulic disc brakes
- Compatible with 10 or 11 sprockets
- Left lever for single or double drive
Shimano Cues ST-U3030
- For mechanical disc brakes
- Compatible with 9 or 10 sprockets
- Left-hand lever for single drives only
Cranks
Shimano Cues FC-U6040-2
- Double (50/34 or 46/32 teeth)
- Compatible with 9 or 10 sprockets
- Hollowtech II technology
Shimano Cues FC-U6040-1
- Single (40 or 42 teeth)
- Compatible with 9, 10 or 11 sprockets
- Hollowtech II technology
Shimano Cues FC-U6030-2
- Double (50/34 or 46/32 teeth)
- Compatible with 9 or 10 sprockets
Shimano Cues FC-U6030-1
- Simple
- Compatible with 9, 10 or 11 sprockets
Front derailleur
Shimano Cues FD-U6030
- As solder-on or clamp version
- Chain line for greater tyre clearance
- Compatible with 9 or 10 sprockets
Brakes
Shimano cues BR-U6030
- Hydraulic brake callipers
- Flat mount for road bikes and gravel bikes
- Only for 160 millimetre brake discs (without adapter)
Jens Klötzer
Editor
