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Cannondale unveils new Synapse: an aero, race-ready mile muncher

Cannondale Synapse Carbon bike in profile parked in Barcelona
(Image credit: Cannondale)

Cannondale's Synapse has been a staple of the American brand's line-up since 2006 and, during this time, it's undergone a few updates to keep it relevant in a market that's constantly evolving. When the Synapse first launched, its hook was its racy geometry, unrivalled compliance and all-carbon-fibre chassis. 

Considered the OG of the best endurance road bike segment, the Synapse forged a reputation as a category-blurring cross-over, equipped to deal with myriad terrain types through the clever use of Save technology (Synapse Active Vibration Elimination) improved frame clearances and disc-brake actuation (in later years). While it's always been a hit among those who enjoy the adventure side of cycling, its popularity only really erupted after Peter Sagan won the Gent-Wevelgem classic aboard the 2013 derivative - proving its all-around ability and raciness.  

The model you see here is the fifth iteration of the Synapse - a bike Cannondale has tweaked to be faster, smoother and safer than any of its predecessors. The big news here is the SmartSense light bouquet controlled via a single battery, which can be double up as a USB-C charging source when it’s disconnected from the bike’s cradle.

Let's take a closer look at the details.

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Cannondale Synapse Carbon LTD RLE

New Cannondale Synapse has a SuperSix look about it (Image credit: Cannondale)
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Cannondale Synapse Carbon LTD RLE

Bikes come in a variety of groupsets ranging from Shimano Dura-Ace R9200 and Ultegra to GRX Di2 and 105 (Image credit: Cannondale)
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Cannondale Synapse Carbon LTD RLE

The GRX derivative will suit those who have dirt-focussed commutes/training routes which take in both pavement and light gravel (Image credit: Cannondale)

What's new?

For version five, Cannondale has made a concerted effort to ensure the ride quality is uniform across the sizing spectrum as ride compliance has always been one of the bike's endearing attributes. This has been carried out through 'Proportional Response' - a unique size-specific blueprint that tweaks the geometry, construction, stiffness index and steering characteristics based on rider size and the difference in centre of gravity. 

As a result, the new model is claimed to be eight per cent comfier than before thanks to the strategic placement of flex zones in the dropped seat stay formation, seat tube and seatpost. These vibration-absorbing measures, however, have done little to adversely affect outright performance thanks to the application of aerodynamic learnings from the SystemSix.

Those who enjoy taking the road less travelled will be happy to learn the new Synapse comes equipped to deal with long days in the saddle. It gets a slew of mounting points including full fender compatibility. Tyre clearance is rated at 35mm, 30mm with fenders in place. It also gets a threaded bottom bracket and the inclusion of an indoor smart trainer axle, while retaining Cannondale's 25.4mm seatpost standard. All models utilise hydraulic disc brakes.

To ensure the Synapse is even more versatile than before it will be available in two versions: an EU-specific and international-spec Synapse, which differ by way of SmartSense light hardware (the EU version complies to the best StVZO bike lights standards).

Modern Cannondale road bikes are often criticised for looking the same and, while this works well from a DNA perspective, this cookie-cutter-like design approach can be confusing to the outsider. Overt model designation hasn't been the brand's strong point in recent years and you really need to look hard to distinguish model from model. The pseudo-SuperSix look of the new Synapse doesn't make things any easier but the rear-slanting top tube, SmartSense battery pack in the inner downtube and external cables are a dead giveaway. Front end cable faff is a common theme on the new Synapse - even on the range-topping models - where a combination of brake hose and SmartSense light cables take centre stage.

That said, the colour palette is quite comprehensive and boasts ten new shades (model dependent of course). These include purple haze, jet black, black cherry, beetle green, black pearl, cool mint, charcoal gray, quicksand, gunmetal green and stealth gray. The Cannondale wordmark logo is also used differently throughout the range. While all models get the new Cannondale 'C' logo on the headtube and diminutive wordmark placed along the top tube, the Synapse Carbon LTD RLE is the only model in the line-up to get a prominent Cannondale logo along the downtube.

The bike is available in six sizes: 48, 51, 54, 56, 58, 61. The geometry numbers are pretty much on par with the outgoing model and pander very much to the endurance side of the spectrum. In medium guise (54cm) it's got a somewhat gravel-bike-like stack height of 570mm, short-ish 415mm chainstays and a bottom bracket height of 272mm - all the ingredients of a snappy handling, reactive bike.

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Cannondale Synapse Carbon LTD RLE

SmartSense is an intelligent system comprising lights and radar that actively communicate with the rider, bike and surroundings, and is powered by a single battery (Image credit: Cannondale)
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Cannondale Synapse Carbon LTD RLE

Front end cable faff is a common theme on the new Synapse (Image credit: Cannondale)

Geometry (medium spec)

  • Head angle: 73.1-degrees
  • Seat angle: 73-degrees
  • Chainstay: 415mm
  • Seat tube: 480mm
  • Top tube: 555mm
  • Head tube: 143mm
  • Bottom bracket height: 272mm
  • Wheelbase: 987mm
  • Stack: 570mm
  • Reach: 381mm

SmartSense and the importance of being seen

All models in the Synapse range (bar the entry-level Carbon 4) benefit from SmartSense - an intelligent system comprising lights and radar that actively communicate with the rider, bike and surroundings, and is powered by a single battery. It's a very clever and intuitive system which can be personalised through the Cannondale app. 

 According to David Devine, Cannondale Global Senior Director of Product,  “SmartSense is designed to make road riding more enjoyable for experienced riders, more inviting for new riders and more convenient for everyone. To compliment SmartSense, we redesigned the highly celebrated Cannondale Synapse to be even more versatile than its predecessors. The result of pairing these two products is a seamless relationship between rider, bike and road.”  

It all starts with the front wheel sensor which activates a chain of communications across the entire SmartSense ecosystem. The system comprises a Lezyne-developed 350-lumen front and 85-lumen rear light, a Garmin Varia radar (front and rear) and Varia Core Battery, the latter of which eliminates the need to charge multiple batteries. Battery run time is pegged anywhere between 3 -20 hours depending on mode.

This idea does potentially bring to the light the possibility of a smarter, more centralised solution down the line where battery-free lights, the best cycling computers, Di2/eTap are all powered by a single battery rendering the need for multiple charging ports obsolete.

Cannondale Synapse Carbon LTD RLE

The Synapse Carbon LTD RLE is the only model in the line-up to get a prominent Cannondale logo along the downtube (Image credit: Cannondale)

Model range and pricing

The Cannondale Synapse range will comprise six distinct carbon models that differ by way of groupset and specification level. While the range-topping options are rather dear in pricing there's a decent enough spread on offer to cater for the broader cycling demographic.

The range is spearheaded by the Cannondale Synapse Carbon 1 RLE which gets Shimano Dura-Ace 9200 and a range of Hollowgram Knot components (45 SL wheels and Save SystemBar), yours for £9,000 / $9,000. This is followed the £6,750 / $7,000 Shimano GRX Di2-equipped Carbon LTD RLE (with similar spec appointments), the £5,800 / $5,500 Ultegra Di2-specced Carbon 2 RLE, the UK-only Carbon 2 RL Ultgera mechanical pegged at £4,000 and the £3,200 / $3,300 Carbon 3 L with Shimano 105.

There's also an entry-level £2,400 / $2,400 Synapse Carbon 4, which gets Tiagra and SmartSense compatibility but comes without lights.

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Aaron is Cyclingnews' tech editor. Born and raised in South Africa he completed his BA honours at the University of Cape Town before embarking on a career in journalism. As the former gear and digital editor of Bicycling magazine and associate editor of TopCar, he's been writing about bikes and anything with wheels for the past 16 years. A competitive racer and Stravaholic, he’s twice ridden the Cape Epic and completed the Haute Route Alps. When not riding, racing or testing bicycles in and around the UK's Surrey Hills where he now lives, he's writing about them for Cyclingnews and Bike Perfect


Height: 175cm

Weight: 61.5kg

Rides: Cannondale SuperSlice Disc Di2 TT, Cannondale Supersix Evo Dura-Ace Rim, Cannondale Supersix Evo Ultegra Di2 Disc, Trek Procaliber 9.9 MTB 

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