Cannondale Synapse HI MOD review

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The Synapse is Cannondale’s endurance-oriented road bike that has been in the company’s catalogue since 2006. The frameset was redesigned for 2014 and CTech Editor Matt Wikstrom recently spent some time on it to see what it has to offer.

Cannondale started life as a “bike-packing” specialist in the early 1970s. The company’s first product was the “Bugger”, a trailer for bikes, followed by a variety of bike bags to suit touring. It wasn’t until 1983 that the company introduced its first frame, a touring-specific design that was constructed from aluminium alloy.

Cannondale continued to use aluminium for its frames throughout the ‘80s and ‘90s. The brand introduced several innovations during this period such as its Headshok and Lefty forks for mountain bikes and partnered with Magic Motorcycle to develop Coda Magic cranksets. The latter proved to be the forerunner for contemporary crank design with hollow crank arms, outboard bearings, and an oversized hollow alloy axle.

The dawn of a new century brought with it increased utilisation of carbon fibre by the bicycle industry. Cannondale appeared to resist the new material at first, steadfastly continuing with its aluminium CAAD frames however a carbon/alloy hybrid design, the Six13, appeared at the Tour de France in 2003 before becoming part of the new catalogue for 2005.

2003 is also noteworthy as the year Cannondale filed for bankruptcy. Over-investment in motorsports was to blame but the company was rescued at auction by its main creditor, Pegasus Partners. Motorsports was dumped and Cannondale returned its focus to bicycle manufacture. The investment firm would later sell Cannondale to Dorel Industries in 2008, the current owner of the brand.


Cannondale introduced its first full carbon frameset in 2006 with the release of the Synapse. From the outset, it was designed with comfort as its main priority. The bike utilised “micro-suspension” within the forks and chainstays and the carbon layup was designed to dampen road vibrations.

Almost a decade has passed and the Synapse still features in Cannondale’s catalogue, defining its endurance road range. There are models for both men and women with three versions to suit different price-points. Entry-level bikes ($1,499-$2,199) utilise an alloy Synapse frame with carbon forks; mid-level builds ($2,699-$5,799) utilise a carbon Synapse frame and forks; and for high-end bikes ($5,999-$10,999), there is a high-modulus (HI MOD) carbon Synapse frameset. Each version features the same geometry and there are options for rim or disc brakes.

The design of the carbon Synapse frameset was recently overhauled. A wider bottom bracket was introduced, braced by a seat tube that splits into a fork to create a “power pyramid”. The bike’s micro-suspension was also refined and the diameter of the seatpost was reduced to introduce more flex. Finally, the weight of the frameset was reduced by utilising “Ballistec” carbon fibre, which apparently also offers greater impact resistance.

Before the Ride

For this review, the local Cannondale distributor Monza Imports supplied a 2014 carbon Synapse HI MOD as a custom build with a SRAM hydraulic Red22 groupset and rim brakes.


As mentioned above, the new carbon Synapse has a wider bottom bracket. Cannondale added 5mm to the non-drive side of its BB30 standard to yield BB30A (where A stands for asymmetric). The new standard offers an increase in stiffness without compromising the chainline of the cranks.

The new seat tube design morphs from a tube to a bow before splitting into a fork at the bottom bracket. The bow is designed to flex and forms part of the bike’s micro-suspension while the fork saves weight without sacrificing any stiffness.

The carbon Synapse uses a 25.4mm seat post diameter that is a little more flexible than larger, more conventional, seatpost diameters. And by incorporating the seatpost binder into the top tube of the frame, a little more of the seatpost is exposed for extra flex. When added to the bowing seat tube, the Synapse promises plenty of shock absorption.

The carbon Synapse now uses the same “Ballistec” carbon fibre as Cannondale’s lightweight SuperSix frameset. Ballistec carbon fibre owes its genesis to military applications and baseball bats, and is characterised by high impact resistance while also being stiff and light. The weight and stiffness of the frame is further improved with the use of high modulus (HI MOD) Ballistec carbon fibre.

The Synapse is offered in six frame sizes as shown in the chart below:

Frame Geometry


Cannondale provides a relatively tall head tube to relax the geometry of the Synapse, however top tube lengths remain relatively generous. The size 56 that was reviewed has 60mm trail and 73mm bottom bracket drop that promises a fairly stable and predictable ride. For a detailed chart see the Cannondale website. It’s worth noting that the geometry of the Synapse is essentially unchanged for 2015.

The front triangle of the carbon Synapse has simple lines while the fork legs and stays thin, bow and flare at different points. The front dropouts sit behind the line of the fork blades, a design that continues to confound my eye, while the seatpost binding system accounts for the bulge below the top tube. Interestingly, Cannondale supplies every HI MOD Synapse with a headset that has a light (in the form of two flashing diodes) integrated into the upper bearing cap.

The bike sent for review was a carbon Synapse HI MOD featuring a SRAM hydraulic Red22 groupset with rim brakes, Mavic Ksyrium Elite wheelset, FSA SLK cockpit and seatpost, and a Fizik Alliante saddle, weighing 7.02kg sans pedals and bottle cages (size 56 frame).


The starting price for a carbon Synapse is $2,699 (Shimano 105, rim brakes) while the HI MOD Synapse starts at $5,999 (Shimano Ultegra, disc brakes). For more information, visit Monza Imports and Cannondale.

After the Ride

Cannondale places a lot of emphasis on the comfort afforded by the Synapse, and I agree: the new design offers plenty of insulation from road buzz. At the saddle, in particular, the micro-suspension is very effective at protecting the body, yet there was never any sense that it was soaking up my effort.

I experienced a little buzz and vibration through the handlebars but it was minor when compared to race-oriented bikes. Overall, the Synapse was an easy bike to ride on a variety of terrain. It’s not enough to guarantee all-day comfort but at least it confirms Cannondale’s marketing claims.

There was a downside to the comfort and insulation offered by the Synapse: I was deprived of the hum from the tyres and a feeling of life from the frame like there can be for other bikes. This is perhaps the most subjective aspect of any bike, but in this instance, I wasn’t engaged by the Synapse. I wanted to feel more of the road and get more feedback from the bike as it responded to my efforts; instead, the Synapse was still and silent.

I found the stiffness and responsiveness of the Synapse was adequate. The bottom bracket never felt like it was swaying under my weight but there wasn’t much snap or kick to enjoy either. Whether this was a feature of the bike or an effect of the micro-suspension, I can’t be certain, though I suspect it might be the latter.


The steering and handling were both spot on. The Synapse was very easy to control at any speed with plenty of stability that allowed me to relax my grip on the bars during descents. The steering also inspired my confidence: the bike was always ready to take any line I desired and there was never any need for corrections. Indeed, the handling was almost enough to make up for what the Synapse was lacking in ride quality.

I’ll leave my thoughts on SRAM hydraulic Red22 groupset for a separate review where I’ll be comparing the rim brakes with disc brakes. Suffice to say, there were no shortcomings with the groupset or the rest of the build.

Final Thoughts and Summary

Cannondale’s carbon Synapse is targetted at endurance and gran fondo riders, those enthusiastic and dedicated cyclists that fail to identify with the more aggressive racer set. The bike offers a relaxed fit and keeps pace with developing market trends by offering a new bottom bracket standard and the choice between rim and disc brakes.

There is no doubting the effectiveness of the Synapse’s “micro-suspension”, which protects the rider and provides a smooth ride. However, it also seems to rob the rider of any perceptible ride quality, which may be ideal for riders devoted to “crushing” the terrain on their way to completing another all-day ride. I was left wanting for more connection with the bike.

In contrast, the steering and handling of the Synapse was as good as it gets for a road bike. It is precise enough to allow an aggressive rider to attack descents and corners with enormous confidence and stable enough for everybody else to relax and enjoy the scenery.

Cannondale Synapse HI MOD Gallery

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