The new 2025 Cannondale Synapse takes its inspiration from the SuperSix Evo, but adopts frame-flex technology from the SuperX.
The latest iteration of Cannondale's endurance bike platform elevates the humble Synapse to the same level as the pro-tour proven SuperSix Evo.
With a raft of bikes available at launch (and a couple more models coming in June), the new Synapse will cover all levels, from the Shimano 105 mechanical-equipped Carbon 5 to a new Lab71 SRAM Red AXS XPLR model complete with a power meter.
That marks a return to the highest-level specifications for the Synapse – something Cannondale didn’t offer on the previous 2022 model.
New Synapse frame design
The new bike brings plenty of what we would expect from Cannondale.
First up, the Synapse retains its BSA bottom bracket and uses the Delta Steerer from the SuperSix Evo. This brings standardised parts from the rest of Cannondale’s drop-bar offerings to the Synapse.
For simplicity, it shares the same thru-axles, rear hangers, stems and even the SuperSix Evo’s slim aerodynamic seatpost.
Add in huge 42mm tyre clearances (all models will ship with 32mm tyres), down-tube storage and mudguard/fender eyelets, and the new Synapse is a bike with practicality at its core.
Geometry tweaks
The geometry of the new bike is largely unchanged, although Cannondale has relaxed the head angle down from 73 degrees on the previous bike to 71.5 degrees.
This, and the advent of larger tyre clearances and larger stock tyres, has increased the wheelbase and trail figures, with the chainstays lengthened to 43cm from 41.5cm to account for 42mm tyre clearance.
The trail rises to 61mm from 59mm, bringing the Synapse in line with bikes such as Cervélo’s latest Caledonia 5. It's only 3mm longer than its racing brother, the SuperSix Evo (58mm).
As for the Synapse's appearance, it's very much now a companion to Cannondale’s performance bikes. The head tube, down tube, top tube and dropped stays all bear plenty of similarities to the latest SuperSix Evo, while the kinked and flattened seat tube follows the same design cues as the latest SuperX.
Cannondale tells us this gives similar compliance figures to the SuperX, too. The overall compliance of the new Synapse is up 20% over the previous model, while Cannondale has improved the vital stiffness figures at the head tube and bottom bracket.
Aerodynamics matter for endurance
A focus on aerodynamics is also at the heart of the new design. Cannondale’s aerodynamics expert Nathan Barry explains: “Much of what we learnt from the Evo-derived performance is here, from the cockpit integration to the highly truncated airfoils (first used on the third-generation SuperSix Evo).
"Our performance-driven design is more about speed and efficiency for the Synapse. Aero is the biggest factor, much more than weight. Bike weight is a very small factor, weight is more about the rider than the bike.”
That said, Cannondale hasn’t exactly delivered a hefty bike with the new Synapse, with claimed frame weights of under 1,000g for the Hi-Mod frame, 1,150g for the standard Carbon and 900g for the Lab71 edition. The Hi-Mod fork adds 445g and the standard Carbon 494g.
Lab71 brings 1x for the road
The move to a 1x drivetrain is something of a shock move on a mainstream production road bike, outside of niche brands such as Vielo and its R+1, but one that we’ve seen coming – especially since Wout van Aert used SRAM’s 1x setup for Milan-San Remo back in 2023.
We saw the same move from van Aert again at this year’s Paris-Roubaix, with the Lidl-Trek team using XPLR rear derailleurs in Paris-Roubaix Femmes.
The Lab71 has a full Red AXS XPLR group, with a 10-46 13-speed cassette matched to a 40-tooth chainring. I’m expecting delivery of this bike any day now, so I’ll report back on how this gravel setup fares on the road.
SmartSense is back
Perhaps the most divisive element of the previous Synapse was the integration of SmartSense, which incorporated an integrated front light, rear light and rear radar using Garmin’s tech, all running from a down-tube mounted single battery.
While initially sceptical about the rear radar, after using it when testing the bike, I became a convert. The added safety of knowing what’s approaching from behind and at what speed makes riding on busy, fast roads safer. I now use a Garmin Varia RCT715 for my regular 30-mile each-way commute.
The issue with the system, however, was a rather clunky integration. The external battery, chunky light and the bracket all added weight, and didn’t have the seamless integration you’d expect from Cannondale design.
Lighting up Lachlan
The new Synapse does a much better job, and when Lachlan Morton rode the as-yet unreleased Synapse for his record-breaking lap around Australia, he employed the full SmartSense setup.
The new front light, made in conjunction with LightSkin, is much slimmer and more slickly integrated into the underside of the cockpit. It’s also much more powerful at 800 lumens (400 for STVZO-compliant countries). The rear light/radar is more minimal, too.
The central battery has a higher capacity of 43.5Wh. It is hidden within a down-tube storage chamber, which also houses storage bags for tools and spares. The storage even includes a built-in flashlight.
The battery also powers the AXS shifting on SRAM-equipped bikes. It can be recharged in place through the USB-C port or removed and charged off the bike.
Any possible battery woes affecting shifting have been considered, with protection for shifting built in. Cannondale tells us the battery, at 5% charge, still has a higher capacity than a standard SRAM AXS battery.
SmartSense is available on all SRAM-equipped bikes, whereas Shimano bikes, both electronic and mechanical, are non-SmartSense models.
SmartSense components will be available aftermarket, should you want to add the system later.
What is the new Synapse?
The frame design has an emphasis on aero and integration on one hand, like the most popular 2014 iteration of the Synapse. On the other hand, it has huge tyre clearances, SmartSense tech and a flagship bike that comes with a gravel groupset.
Is the new Synapse an all-roader biased endurance bike that's more in line with the BMC Roadmachine than the Giant Defy?
I think it’s somewhere in between – a performance endurance bike with a go-anywhere spirit. It’s a bike designed for a new breed of rider at the highest level, personified by Lachlan Morton, who’s at home in any discipline and at a tremendous pace.
If the Synapse lives up to these (my) expectations, it could be the ultimate do-it-all bike – equally at home in the cut and thrust of fast-paced road rides, gravel excursions, and epic days, weeks, or more.
If it’s good enough to aid Morton in setting the record of a 14,200km lap of Australia in an astonishing 30 days, 9 hours and 59 minutes – averaging over 450km a day – it’s going to be enough bike for most of us.
2025 Cannondale Synapse range details
There are eight models in the new Synapse range, although the details of four are embargoed until 17 June.
The range starts with the Carbon 5 at £2,995 / €3,499 / $3,599 and is topped by the new Lab71 Synapse (as ridden by Lachlan Morton), priced at £13,000 / €15,799.
Cannondale Synapse Lab71 SmartSense
- SRAM RED AXS XPLR 1x 13 with power meter
- SmartSense Gen 2 system
- Reserve 42/49 Turbulent aero wheelset
- Cannondale SystemBar
- Fizik Argo Carbon 00 saddle
- £13,000 / $16,499 / €15,799 / CA$22,099
Cannondale Synapse Lab71 frameset
- Lab71 hi-mod frame
- Lab71 hi-mod carbon fork, headset
- Cannnondale C1 Aero 27 carbon post
- Stash bag, down-tube storage bag
- £4,950 / $5,999 / €5,799 / CA$8,099
Cannondale Synapse Carbon 1
- Synapse Hi-mod carbon frame
- Synapse Hi-mod carbon fork
- Shimano Ultegra Di2
- Reserve 42/49 wheelset
- Fizik Vento Argo R5 saddle
- £7,500 / $9,399 / €9,199 / CA$12,899
Synapse Carbon 2
- Synapse carbon frame
- Synapse carbon fork
- Shimano Ultegra Di2
- Reserve 42/49 wheelset
- Fizik Vento Argo X5 * saddle
- £5,995 / $7,499 / €7,199 / CA$10,099
Synapse Carbon 4
- Synapse carbon frame
- Synapse carbon fork
- Shimano 105 Di2
- DT Swiss R470/Shimano wheelset
- Fizik Vento Argo X5 saddle
- £3,995 / $4,599 / €4,499 / CA$6,299
Synapse Carbon 5
- Synapse carbon frame
- Synapse carbon fork
- Shimano 105 12-speed mechanical
- DT Swiss R470/Shimano wheelset
- Fizik Vento Argo X5 saddle
- £2,996 / $3,599 / €3,499 / CA$4,899
Cannondale says it will announce full details of the Synapse Carbon 2 SmartSense and Synapse Carbon 3 SmartSense on 17 June.
