Shimano CUES is a genuine game-changer for shops, bike brands and consumers, many years in the making. What Shimano have done here is merged the three-lowest tiers across mountain bike and flat-bar road/city groupsets, from Deore and Tiagra down, into one family: CUES (Creating Unique Experiences). Shimano have “have all but confirmed” that CUES componentry for drop bars is coming, but not until later this year.
For the last three decades technological advances have happened to the highest-spec racing-oriented groups like Dura-Ace and Ultegra, and then trickled down through the ecosystem over the years. That goes out the window today, with all CUES groups using the same fundamental technology - Linkglide - leaving consumers and bike brands to choose based on needs and budget, and not be left wanting for longevity or performance. Linkglide is here predominantly to solve the problem of e-bikes eating traditional drivetrains - but the benefits can be had by any cycling paradigm, be it commuting, touring, bikepacking or 'acoustic' MTB.
> Read the launch story here: Shimano unveils new cross-compatible CUES groupsets, consolidating Claris, Sora and Tiagra
There are three levels of CUES spec/quality/price: U8000 in 11-speed, U6000 in 10-speed, and U4000 in 9-speed. U8000 gets nicer finishes - think XT or Ultegra nice. As you go lower, the finish and design leans more towards the value end of the spectrum.
Critically, all CUES groups use 11-speed chains. This is a major departure on previous thinking where the chain width matched the number of gears. This means everyone can run one model of chain across most all of their bikes, and bike shops only need to stock one type of chain for most geared bikes.
This shift in thinking is driven by Shimano’s knowledge of how chains and sprocket teeth interact - and 11-speed chains are the optimum for tooth-chain contact. You can use other brand 11-speed chains if needed/desired without detracting from performance - the Linkglide shift tech is built into the teeth ramps, not the chain.
Speaking of teeth, all CUES cassettes use Shimano’s Linkglide technology, launched last year for electric mountain bikes. Basically thicker, taller all-steel teeth that engage better with the chain and are far more resistant to wear, skipping or breakage.
Shimano claims Linkglide lasts three times longer, shifts far quieter, and is much more forgiving of mis-shifting under full load, which is important for e-bikes. This also means you can run wide-range 9- or 10-speed cassettes with no horrific shift degradation due to large jumps between sprockets. CUES gives you 11-46T in 9-speed, 11-48T in 10-speed, and 11-50T in 11-speed.
Another benefit is that the quickest-to-wear 11T and 13T cogs are available as parts if needed, and they are interchangeable across the range - more maintenance and consumer cost-saving goodness.
I’ve been riding my Bosch CX-powered 85Nm full-fat e-MTB equipped with a Linkglide 11-speed drivetrain all winter on steep red and black trails. Not a single mis-shift, dropped or broken chain, or even crunchy-geared complaint, no matter how much abuse I threw at it. After 500 miles the Linkglide LG500 chain is only half-worn according to my digital chain checker, and it’s just a £30 replacement.
What this means for consumers is that CUES parts will last far longer than you’re used to, shift better, quieter, and cost much less to maintain. Wins all round.
Another major win is that all pull ratios and cog spacings are the same. So you can mix 9, 10 or 11-speed CUES cassettes and mechs with different CUES shifters, and all that will happen is that you’ll lose one or two gears at the top or bottom (you decide), or hit the travel limit with a few clicks to spare. This is a huge boon for people travelling with bikes and needing emergency repairs, or when supply chain issues strike, or when you trash a mech or shifter the day before a trip and the local shop is out of your exact spec. Just grab what’s available, off the shelf or another CUES-equipped bike, and it’ll work fine.
Likewise the front mechs are all running the same pull ratios. This pull-ratio standardisation front and back will be music to the ears of gravel-bikepacker-touring folks, who for years have had to hack around with different combinations and ratio adaptors to get working combinations in the gear range desired. Once CUES appears on drop-bar levers, there shall be much rejoicing and many new combinations supported without hackery or faff.
Diving into some of the differentiators amongst the CUES levels: The U4000 mech doesn’t have a clutch, but Shimano have installed a heavier spring and tweaked the design, and with Linkglide plus a narrow-wide 11-speed chainring, chain retention won’t be an issue for the focus city/trekking market. And retro-grouches rejoice... you get a barrel adjuster on the mech.
The U4000 crankset is a square taper, meaning it can be retrofitted to many existing bikes. The chainrings are riveted, unlike the U6000 and 8000, where they are bolt-on and therefore replaceable. The U8000 crankset is the lighter HollowTech II spec, while the U6000 is Shimano '2-Piece’, which looks and installs the same as HollowTech II but is heavier. All CUES levels get single and double-ring chainsets, and there are front mechs to match.
Cassette-wise, there's three options: a low-spec LG300 to match the 2 x 9 setup, the workhorse LG400 that will be on most bikes, and the lighter LG700 top tier spec. Gone is the LG600 placeholder launched last year.
The U8000 and 6000 shifters come with or without visual indicators, and two-way trigger release. The U4000 shifters have indicators only, and one has the two-way option for release.
For e-bikers riding Shimano STEPS motors, there are two CUES Di2 rear mech options that support new auto-shifting options. There’s a 10-speed for up to 43T and an 11-speed for 50T - again Linkglide ready. Auto-shifting is configurable to get you into the right gear based on speed and cadence - using the motor to power the chainring forward to shift gears, even if you’re coasting or stationary. You can also select the gear yourself, without pedalling. Nice.
Another bonus of wired electronic shifting on e-bikes is that this is much cheaper to do using CUES than SRAM AXS, meaning no more rear shift cables to replace, ever. Plus no shifter or mech batteries to charge.
Whilst no one has yet ridden a CUES groupset, my experience on Linkglide in the toughest of conditions has been faultless, so I have every reason to believe these new groups will be performance winners. Likewise, the longevity, cost-effectiveness and standardisation as well as repairability all add up to a great consumer and trade bonus. Writing as a small bike service business owner, I can’t wait to see CUES become widespread across my customer’s fleet. It will make holding spares much easier to do, speeding the turnaround of repairs and enabling me to support emergency repairs better.
The flexibility, options and performance vs. value points that CUES now open to bike brands, shops and consumers is a genuine step change. SRAM and other brands will have a real challenge reacting anytime soon with products to match. Chapeau Shimano, chapeau.