We’re pretty big fans of the Cannondale Synapse here at Road Cycling UK. The SRAM Red eTap build of the American manufacturer’s carbon fibre endurance bike was included in the most recent RCUK 100, and when the chance came along to test the mechanical Dura-Ace version, we thought it was only fair to give it a spin to make sure that it wasn’t a one trick pony.

Having ridden this build pretty consistently for the past month, I can confirm that yes, Cannondale is onto a winner with the Synapse.

The company’s endurance platform has been around since 2006, but underwent a complete makeover for the 2018 range. The geometry is the same as always, but Cannondale has gone back to the drawing board and looked to boost the frame's stiffness while shaving off some weight.

The frame - Hi-Mod carbon, relaxed feel but racing nous

The Synapse is available in both Ballistech carbon or a ‘Hi-Mod’ Ballistech lay-up. The technology is Cannondale’s in-house method for carbon construction, with the Hi-Mod variety boosting the standard base structure with ‘a sophisticated mix of high and ultra-high modulus fibres to create the stiffening network’.

This all sounds rather, well, ‘stiff’ for an endurance bike. To counter this, Cannondale has tuned it at four different points (seat tube, chainstays, seat stays and forks) with its ‘SAVE micro-suspension’ to soften the ride a bit and smooth out the roughest of roads.

"The frame’s relaxed geometry creates a slightly more ‘up right’ feel to the ride, which keeps things a comfortable on trips measured in hours rather than minutes"

An extra wide bottom bracket, twin seat tubes and asymmetric chainstays help with power transfer when laying it down on the tarmac, while the frame’s relaxed geometry (the 56cm frame has a 73° head tube angle) creates a slightly more ‘up right’ feel to the ride, which keeps things a comfortable on trips measured in hours rather than minutes.

The forks are also asymmetric - countering the imbalance caused by unequal loads that go through either side of the bike - and given Cannondale’s expertise and experience in this area (the brand’s innovative Lefty MTB fork turns 18 this year), you trust that they know what they’re doing.

The frame is the same as that found on the Dura-Ace Di2 build, so a hole for the battery unit is included on the downtube - meaning that an electronic upgrade is possible further down the line. It will only ever run disc brakes though, with there no mounts or pre-drilled holes in the frame and fork. Flat mounts are found at either end, as are thru axles.

The ride - a perfect companion for all conditions

In practice, all of this translates to an extremely lightweight build (Cannondale claims that the frame weighs just 950g) that I’ve found to be as much at home on the Alpine climbs of Switzerland as it was in the rolling lanes of the home counties.

That Hi-Mod carbon lay-up also makes the Synapse extremely responsive - although not so fidgety that you feel like you’re fighting with it the whole time. Out of the saddle, I found I could keep up with most aero-totting riders, while it had a reactive kick when switching the tempo up while climbing.

"The micro-suspension performs excellently and smooths out the roughest of roads. Throw in space for 32mm tyres and you’ve got the base for an all-road gobbling machine"

Despite these capabilities though, the Synapse is still an out-and-out endurance bike at heart that is a great companion for longer rides. The top tube’s not so relaxed that you’re going to slip off the saddle, but helps to prevent the bunched up feeling you can get on some aero bikes.

That comfort doesn’t just come from how you’re positioned on the bike though. The micro-suspension (which is also included in the seat post) performs excellently and smooths out the roughest of roads. Throw in space for 32mm tyres, which is made possible by the removal of the chain and seat stay bridge, and you’ve got the base for an all-road gobbling machine.

The build - Shimano Dura-Ace 9120 complemented by in-house System Integration kit

The peak of mechanical perfection in Shimano’s range might be coming towards the end of its three-year cycle, but we’re still fans of Dura-Ace - especially when it comes packed with its super sharp hydraulic disc brakes.

Those Shimano Dura-Ace rotors are paired to a set of Cannondale HollowGram Carbon clinchers. The wheels held speed well and, at 35mm deep, the rims were able to slice through the air with ease, while only the strongest of crosswinds would require extra attention. They’re also tubeless ready, although the 28c Vittoria Corsa tyres supplied were not. But that extra width certainly boosted the overall ride’s comfort, with a tubeless set-up likely to somehow improve this even more.

"The designers’ unwavering commitment to comfort and performance runs down to the bar tape, which includes a gel to help keep the hands fresh on the longest rides"

Cannondale Synapse Hi-Mod Dura-Ace

Price: £4,999

Weight: 6.8 (56cm)

Sizes: 51cm, 54cm, 56cm, 58cm, 61cm

Website: Cannondale

Those looking for a complete Dura-Ace groupset will be left disappointed, but the Hollowgram Si crank and SpiderRing substitutions that Cannondale has made keep things ticking over seamlessly.

In-house products finish off the build and again highlight the designers’ unwavering commitment to comfort and performance - even down to the bar tape, which includes a gel to help keep the hands fresh on the longest rides. The saddle comes from Fabric, while an out-front Garmin mount has been integrated neatly into the stem.

All of this can be yours for £4,999, which although pricey compares favourably with the likes of Specialized’s Roubaix Pro and Giant’s Defy Advanced SL in similar builds.

If I had any criticisms, the only thing I could think of was the colour - and only because I prefer the matt black finish and tan sidewalls of the Red eTap build. Otherwise, the Cannondale Synapse is probably as good as you’re going to get when it comes to a pro-level mechanical endurance bike.


The Cannondale Synapse has been the cycling equivalent of a summer fling - we’ve shared good times in the Swiss Alps, battled wet and windy sportives, and it has been my hardy companion on the daily commute. I’ll be sad to say goodbye, but at least I’ll always be able to cherish our memories together.

If you’re in the market for a fantastic all-rounder, then you can’t really go wrong with Cannondale’s lightweight endurance platform. Throw in one of the best mechanical groupsets on the market, and you’ve got a bike for all occasions.


- Lightweight
- Comfortable
- Responsive
- Easy to ride
- All-road


- Expensive for mechanical build