The all-new Cannondale Synapse shares many of its architectural and design cues with the current SuperSix Evo – and that’s a good thing, as desirability and performance are central to the new bike. Cannondale even views the new Synapse on the same level as the SuperSix Evo, claiming it melds WorldTour-level aerodynamics and stiffness with generous clearance for wider road bike tyres, compliance, and features that appeal to the general rider. These attributes are evident in the aesthetics, geometry, and the way it rides.
The bike pictured here, however, is the range-topping Synapse Lab71 SmartSense, an endurance bike that turns the performance and desirability dial up to 11. At £13,000, it will appeal to the endurance rider looking for the exclusivity the Lab71 moniker brings to the table, but this also places it out of reach for most.
(Image credit: Aaron Borrill)
Construction
Unlike the Lab71 SuperSix Evo, which uses a special Series 0 carbon layup, the Lab71 Synapse is manufactured from Hi-Mod carbon fibre known for its exceptional tensile and compressive strength properties – the result is a sub-1,000g frame. It bears a strong resemblance to the current SuperSix Evo, as evidenced by the narrow head tube, boxy down tube, top tube, and dropped seatstays. There is also some part sharing at play, such as the seatpost, which is used across the SuperX, CAAD13 and SuperSiX Evo Gen 3 platforms. Unlike the previous iteration, SmartSense (comprising an integrated front light, rear light, and rear radar with a battery in the down tube) is now only available on three of the eight models, including the Carbon 2 and Carbon 3 and Lab71 featured here.
The geometry numbers are not too different from the previous-generation Synapse, utilising the same 570mm stack height and 381mm reach, but with a more relaxed head angle of 71.5 degrees, down from 73 degrees. All Synapse models come standard with 32mm tyres, but there’s space at the rear for clearance of up to 42mm and the ability to go as wide as 48mm at the fork.
(Image credit: Aaron Borrill)
As a top-tier offering, Cannondale hasn’t cut any corners with the build. The bike features SRAM’s Red XPLR AXS 13-speed groupset complete with Quarq power meter. It’s a reliable and smooth-shifting groupset thanks to the UDH-mounted rear derailleur’s ability to shift aggressively under load. As a 1x-specific build, it employs a 44T chainring up front and a 10-46T XPLR cassette at the rear, driven by a flat-top chain and 172.5mm carbon cranks. There’s also a beautiful pair of Reserve 42|49 Turbulent Aero wheels that come wrapped in 32mm Vittoria Corsa Pro Control tyres.
Like the Lab71 SuperSix Evo and SuperX, the front end is characterised by a one-piece Cannondale System Bar R-One, designed in partnership with MomoDesign in Italy. Touchpoints include Fizik’s Vento Argo 00 Carbon saddle and Tempo Bondcush bartape. Other notable features include a CeramicSpeed threaded BSA bottom bracket, lightweight thru-axles, and, of course, the SmartSense 2.0 system; the StashPort down tube storage houses the battery on Smart Sense-equipped models but can be used to store a pump, a spare tube, and more.
The Ride
The handling of the Synapse feels a lot like the current SuperSix Evo, and there are hints of the SuperX in there, too – particularly in the way it deals with vibrations and smooths out broken roads. While some of this can be attributed to the tubeless 32mm Vittoria Corsa Pro Control tyres, Cannondale has increased stiffness in the head tube and bottom bracket, while improving frame compliance by 20% over its predecessor to enhance overall performance.
As a result, the frame is incredibly responsive and balances stiffness and comfort superbly well. Despite the longer wheelbase and chainstays over its predecessor, the Synapse still feels pretty nimble and responds eagerly to steering inputs, while being very predictable in the corners and flowing sections of descending Tarmac.
(Image credit: Aaron Borrill)
At 7.79kg in 54cm (without pedals), it’s heavier than you’d expect from a Lab71, but most of the excess weight comes from the SmartSense system. The removable battery alone weighs 300g, and I estimate the balance of the system (the front light, rear radar, and wiring harness) to total around 160g – that’s 460g right there. That said, weight never seems to be a factor with this bike, as you don’t feel it when riding. Part of this stems from its ability to maintain speed over rolling terrain, but also from the friendly gear ratios afforded by the 1x setup. While the 44T, 10-46T does sacrifice some top end, what you lose in speed, you make up for in climbing gears.
The SmartSense system is non-obtrusive and works really well, utilising a single, integrated battery to power all connected components, including the SRAM AXS rear derailleur. The battery provides up to 24 hours of runtime in flashing mode or over 12 hours in steady mode, and the charge level can be monitored via Cannondale’s smartphone app.
Value and conclusion
The Synapse Lab71 SmartSense is a well-rounded bike with balanced geometry. It’s fast, too – even with the comfy 32mm tyres. While it adds extra weight to the package and can be a chore to charge after every ride, the SmartSense system works flawlessly, and the 1x configuration in this particular build keeps things simple without affecting functionality.
In terms of rivals, it goes head-to-head against the Trek Domane SLR 9 AXS Gen 4. Known for its comfort and versatility, it is a worthy alternative to the Synapse Lab71 and, at £9,500, it’s also significantly cheaper while possessing many of the features that make the Synapse such a great option – including the frame storage and hill-friendly gearing. Although it’s lighter (7.5kg), it lacks the simplicity of the Synapse’s 1x gearing, the utility and safety of the SmartSense system, and can’t compete with the 42mm tyre clearance for that matter either.
(Image credit: Aaron Borrill)
The Synapse is one of my favourite bikes of 2025. Having also recently tested the Synapse Carbon 4 (third from bottom in the range), I can confirm Cannondale has done a sterling job when it comes to keeping the ride character and handling manners the same throughout the range. Regardless of which bike in the range you choose, it neither feels nor looks like a traditional endurance bike, and this should see it find favour with a host of new customers.
That, however, doesn’t excuse the price of the range-topping Synapse Lab71 SmartSense I tested. At £13,000, it’s simply outrageous for an endurance bike designed for the general rider. While this puts it out of reach for many, the upshot is a comprehensive range that spans specification and pricing levels to suit most budgets.
Specfications
Frameset: Lab71 Synapse Hi-Mod Carbon
Fork: Lab71 Synapse Hi-Mod Carbon
Cockpit: Cannondale System Bar R-One
Seatpost: Cannondale C1 Aero 27 Carbon
Groupset: SRAM Red XPLR AXS 13-speed
Wheelset: Reserve 42|49 Turbulent Aero wheels
Weight: 7.79kg
