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Cannondale Synapse Carbon 2 RL review

A superb endurance bike that brings something new to the genre

Our rating 
4.0 out of 5 star rating 4.0
GBP £4,000.00 RRP | EUR €4,499.00
Male cyclist riding the Cannondale Synapse Carbon 2 RL endurance road bike

Our review

The new Synapse is a refined endurance bike that’s easy to live with and brings safety-enhancing tech as standard
Pros: Supple smoothness wrapped around swift, exciting handling; clever tech brings day and night safety
Cons: Not everyone will want all of the equipment; alloy components and middleweight wheels feel like a downgrade
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The Cannondale Synapse has helped define the endurance bike genre for more than a decade and this latest iteration provides a familiar blend of performance and comfort, with a fresh focus on practicality.

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That means the Synapse now has clearance for 35mm tyres and a threaded bottom bracket but, more significantly, it comes with Cannondale’s integrated SmartSense light and sensor system.

We’ve covered all the finer details in our 2022 Cannondale Synapse news story, so here I’ll focus on the key changes and, more importantly, the performance of the mid-range Synapse Carbon 2 RL.

It offers all the smoothness of a Synapse, with exciting handling, and the clever tech brings an element of additional safety to rides, though not everyone will want those add-ons and some of the component choices on this model feel like a downgrade.

Synapse, SuperSix and SystemSix

The Cannondale Synapse has undergone some appreciable changes in its latest guise, each of which trends towards the practical while deviating away from the brand’s racier SuperSix EVO and SystemSix bikes.

Now, depending on your point of view, this is either a series of good sensible updates or a series of retrograde steps.

Personally, I’m generally in favour of the changes. The simple seat binder stops any potential hassles from wedge-type seat clamping and the woes this can entail, especially when travelling. If you’ve ever lost the wedge of a seat clamp into the abyss of a seat tube, you’ll know what I mean.

The simpler cable routing makes the Synapse the traveller’s friend too, while lots of people will rejoice at the BSA bottom bracket.

I’m a long-term Cannondale owner and have Synapse and Slate bikes. They’re both equipped with BB30 and neither have had any issues with creaks or squeaks, as some owners have reported. However, I can see the practicality of the new Synapse’s threaded BB, especially when it comes to upgrades or replacements, giving us more choice.

These changes, along with the new-shaped frame with dropped seatstays, put it in line with the rest of Cannondale’s drop-bar offerings (Topstone, SuperSix EVO, System Six).

Pack shot of the Cannondale Synapse Carbon 2 RL endurance road bike
The Synapse Carbon 2 RL, at £4,000, comes with full Shimano Ultegra, Fulcrum wheels and Cannondale’s new integrated lights and radar.
Russell Burton / Immediate Media

The new tube profiles, designed to bring aerodynamic advantages to the Synapse, are a welcome return to the 2010 model, which rather radically first debuted aero shapes on an endurance bike.

Add in more fittings (mudguard mounts front and rear, a gravel-style top tube bento box set of mounts, plus mounts for the new “SmartSense” power pack) and more tyre clearance, and you wouldn’t expect the new Synapse to come close to the previous model’s svelte lightweight design. However, Cannondale says the new Synapse chassis is the same weight as the 2018 model.

Cannondale Synapse Carbon 2 RL ride quality

Male cyclist riding the Cannondale Synapse Carbon 2 RL endurance road bike
The handling is swift and controlled. It’s a close match to both the preceding model and Cannondale’s brilliant SuperSix EVO.
Russell Burton / Immediate Media

Having said all of the above, the practical changes could have risked dulling the Synapse Carbon 2 RL’s ride quality. Thankfully, having spent some time aboard the bike over the Christmas break, on the road the bike retains all the charm that made its predecessors so well received.

As soon as I got on the new Synapse Carbon 2 RL, it felt welcomingly familiar. Cannondale has certainly taken an ‘if it ain’t broke don’t fix it’ mantra to heart when it comes to its latest creation.

My 58cm test bike almost perfectly mirrors my own personal 2014 Synapse’s geometry, with a 610mm stack height and 393mm reach. The wheelbase, at 1,011mm, is a little longer, but then this latest bike gets much more tyre clearance (up to 35c from 30c).

The trail on the new bike is reduced to 56mm (from 58mm). This brings the handling response in line with the SuperSix EVO. The new Synapse has a real zip to it when you want to quickly make direction changes or correct your line mid-corner.

This latest Synapse may be wrapped in sensible tech, suggesting a mature mindset for potential riders, but it does have a wild side and responds with vigour when you want to put in big efforts.

Cannondale Synapse Carbon 2 RL 2022 geometry

Seat angle (degrees)737373737373
Head angle (degrees)71.371.473.173.273.373.4
Chainstay (mm)415415415415415415
Seat tube (mm)407443480520550590
Top tube (mm)533544555567579598
Head tube (mm)109130143164187218
Fork offset (mm)555545454545
Trail (mm)595858575656
Bottom bracket drop (mm)757573737070
Bottom bracket height (mm)270270272272276276
Wheelbase (mm)9911,0009879981,0111,028
Standover (mm)712742773787833868
Stack (mm)53055057059610640
Reach (mm)371376381387393402
Male cyclist riding the Cannondale Synapse Carbon 2 RL endurance road bike
The bike responds well when you want to give it some beans.
Russell Burton / Immediate Media

Cannondale Synapse Carbon 2 RL wheels and tyres

It does, however, have an Achilles heel in this specification, and that’s the rolling stock.

The Vittoria Rubino Pro G2.0 tyres, in a generous 30c width, meld with the frame’s vibration damping to create a ride that’s as smooth as I’d ever want.

However, the tyres don’t exactly light up when it comes to acceleration, and they’re wrapped around some rather underwhelming wheels.

The Carbon 2 RL comes equipped with Fulcrum’s Rapid Red 900 wheelset. That means an alloy rim that’s a shallow 24mm with an internal rim dimension of 22mm.

They are specified as “two-way fit”, so they can be used with clinchers and inner tubes (as here) or with tubeless tape and tyres. The internal width of the rim is a decent match for the 30mm tyres, supporting their wide carcass well.

Warren Rossiter riding the 2022 Cannondale Synapse
The Synapse retains a blend of performance and comfort, but the rolling stock is holding this model back.
Russell Burton / Immediate Media

The 28-spoke front and rear build uses stainless steel spokes in an easy-to-source J-bend shape, as well as proper brass nipples. They are accessibly built, and for the keen home mechanic should be simple to source parts for and maintain. The hubs are built around sealed cartridge bearings, which is again a sensible choice.

The wheels’ 1,950g weight, however, does make them somewhat noticeable, especially when the gradient starts to steepen. With lighter wheels in place, this Synapse would put a bit more sparkle into its climbing responses.

I’ve no complaints about the quality of the wheels – the hubs are fuss-free and smooth, and the freehub picks up with enough zip to make the bike feel plenty responsive enough – but there’s no getting away from the fact that wheels of this level would have come as standard on far cheaper bikes a few years ago.

The global situation as it is though, with shortages and pricing pressures being what they are, and this type of wheelset is now, unfortunately, pretty much expected on bikes at this price point.

Cannondale Synapse Carbon 2 RL gears and brakes

Male cyclist riding the Cannondale Synapse Carbon 2 RL endurance road bike
The Synapse is a bike designed for long days out.
Russell Burton / Immediate Media

Shimano’s mechanical Ultegra R8000 has been around since 2017, so I don’t have much more to say on its performance. Shifting is superb, the levers have great ergonomics and provide great braking feel, too.

Cannondale hasn’t cut corners and has a full group including the all-important Ice-Tech rotors, which offer quiet running and rub-free performance.

The 50/34 compact chainset, paired with a broad 11-34t cassette, is ideal for the remit of an endurance bike, giving plenty of range and a 1:1 gear for the steepest slopes. Again, the inclusion of an Ultegra mechanical group shows just how pricing has increased in a relatively short period.

The 2018 Synapse Carbon Ultegra (the first model year to use the R8000 group) retailed at £2,699, with alloy wheels and alloy components. In four years, the price has increased by £1,300. Even considering the new Synapse’s extra tech, that is still quite the price hike (it’s the same for Cannondale’s rivals, too).

As an aside, unfortunately there’s no word on the availability of the new, electronic-only Shimano Ultegra R8100 groupset yet, but we’ll update you when we hear more.

Cannondale Synapse Carbon 2 RL finishing kit

Cannondale Synapse Carbon 2 RL endurance road bike cockpit and top tube
The Synapse frame now features gravel bike-style top tube (bento box) mounts.
Russell Burton / Immediate Media

The Synapse 2 RL’s equipment is all sensible stuff. The Fabric Scoop saddle is an established classic and one seriously comfortable perch.

The Cannondale Three is a standard alloy seatpost with an offset clamp, and Cannondale has reverted the Synapse to a 27.2mm-diameter post rather than the skinny 25.4mm of the previous model.

While it’s a little less fancy, it does increase the scope for finding upgrade options. Just make sure you find one where the cable for the SmartSense can be routed through the post and into the seat tube.

For a bike of the Synapse’s ilk, I’d have liked a carbon post akin to the excellent SAVE carbon post of the old model. An alloy post on a £4,000 bike doesn’t exactly scream good value.

The simple alloy stem and compact drop alloy bar are perfectly serviceable items, though step up to the RLE model and the bike’s front end is transformed by the slick aero styling of the SAVE carbon bar and KNØT stem, as seen on the top-end SuperSix EVO and Topstone gravel bike.

Like the post, the alloy cockpit components are both tidy and serviceable, but you’ll see the same components on the £2,400 Synapse Carbon 4, or Cannondale’s CAAD alloy bikes.

Cannondale Synapse Carbon 2 RL bottom line

It may sound as though I’m somewhat down on this new Synapse. That’s certainly not the case, and I’d rather be testing a bike from the more affordable end of the range on launch rather than the one dressed up with the best of the best (and with a price tag to match).

Barring a few underwhelming spec choices, the new Synapse rightfully keeps its place as one of the best endurance bikes around. It’s up there with the likes of the Specialized Roubaix, Giant Defy and Cervélo Caledonia.

Its geometry creates what I love about great road bikes, offering a compelling mix of sure-footed stability and nimbleness.

Cannondale Synapse Carbon 2 RL endurance road bike SmartSense app
Cannondale’s SmartSense is controlled through a clever app.
Russell Burton / Immediate Media

The addition of the SmartSense extras is the icing on the cake, but I’d still be smitten with the Synapse’s charms if it came shorn of these safety- and utility-enhancing extras.

I like that Cannondale has brought this type of technology into the Synapse. It’s all very practical and reflects the needs of riders in the real world.

Cannondale Synapse Carbon 2 RL endurance road bike
The front light was designed in conjunction with Lezyne.
Russell Burton / Immediate Media

On the road, I really appreciated the stVZO light when riding on busy roads and two-way bike paths without hindering other road users. However, the lack of power (maximum output is 350 lumens) meant a more cautious approach when riding in full darkness on unlit single-car-width lanes.

Similarly, once I became used to the Varia system, I could appreciate its usefulness. Initially, I found myself more often than not checking over my shoulder as usual. I found it most useful when riding at night, where it pays to keep your eyes on the road rather than looking behind (potholes and debris are harder to spot at night).

The downside is that lots of riders will already have decent bike lights so may see the system as unnecessary, especially if you need more power than what Cannondale offers. It also means that the standard weight of the Carbon 2 RL tested here looks, at least on paper, hefty compared to the competition.

Male cyclist riding the Cannondale Synapse Carbon 2 RL endurance road bike
You needn’t worry about losing the light when riding the new Synapse.
Russell Burton / Immediate Media

At 9.89kg (complete with radar, lights, bottle cage and power pack), it certainly sounds heavy. Though add the weight of all those accessories to any of its rivals and the Synapse Carbon 2 RL would be competitive due to its comparatively light frameset.

At £4,000, and coming with a Shimano Ultegra R8000 mechanical groupset with alloy components and alloy wheels, the Synapse doesn’t look like the most competitively priced bike.

One of its major rivals, the Specialized Roubaix, in its closely matched Comp (8.66kg, 58cm) specification, comes in at £3,700 (with alloy DT Swiss R470 wheels and a carbon seatpost).

Male cyclist riding the Cannondale Synapse Carbon 2 RL endurance road bike
The ride quality is noticeably smooth.
Russell Burton / Immediate Media

I’d argue, however, that the new Synapse, at £300 more, does come with excellent lights. And then there’s the Radar system – buying that aftermarket would cost another £130. So, while I wouldn’t exactly call the Synapse Carbon 2 RL great value, the price is understandable in the context of the market.

The new Synapse is a bold step, which I’d say has paid off. Cannondale has created perhaps the most sensible road bike available today. A set of mudguards included as standard would top things off for me, though.

The inclusion/integration of the lights creates an uncluttered front end, without the woes of losing clamps and parts when not using the lights. Having a single battery to worry about keeping charged is a practicality plus, too. Balanced against that, it does mean you are carrying the lights all year round and the lines aren’t as clean as they would be otherwise.

Male cyclist riding the Cannondale Synapse Carbon 2 RL endurance road bike
The inclusion of lights signals a new era for endurance bikes.
Russell Burton / Immediate Media

That said, thanks to some smart design touches, the Synapse wears that aforementioned sensibility without being boring.

It handles swiftly, with assured, confidence-inspiring, line-keeping directness. Its rubble-smothering smoothness made me want to push it on to higher speeds, especially on descents, where it oozes the traits that make its lightweight sibling, the SuperSix EVO, such a stand-out machine.

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If the SystemSix is Cannondale’s F1 car, and the SuperSix EVO its road-going supercar, then the Synapse is a big, powerful GT. It gives 90 per cent of the speedsters’ charms and brings practicality for anyone not looking to race, but instead looking to go far and fast.

Product Specifications


Price br_price, 5, 3, Price, EUR €4499.00GBP £4000.00
Weight br_weight, 5, 6, Weight, 9.89kg (58cm), Array, kg
Year br_year, 5, 9, Year, 2022
Brand br_brand, 5, 10, Brand, Cannondale


Features br_Features, 11, 0, Features, Cannondale Smart sense wheels sensor
Cannondale/Garmin Varia radar
Cannondale Lezyne rear light
Cannondale/Lezyne front STVZO light
Cannondale/Garmin Varia display
Cannondale bottle cage
Cannondale 750ml bottle
Trainer ready rear thru axle caps
Available sizes br_availableSizes, 11, 0, Available sizes, 48, 51, 54, 56, 58, 61cm
Brakes br_brakes, 11, 0, Brakes, Shimano Ultegra hydraulic disc
Cassette br_cassette, 11, 0, Cassette, Shimano Ultegra, 11-34
Cranks br_cranks, 11, 0, Cranks, Shimano Ultegra, 50/34
Fork br_fork, 11, 0, Fork, Carbon
Frame br_frame, 11, 0, Frame, Carbon
Front derailleur br_frontDerailleur, 11, 0, Front derailleur, Shimano Ultegra
Handlebar br_handlebar, 11, 0, Handlebar, Cannondale TWO Alloy
Rear derailleur br_rearDerailleur, 11, 0, Rear derailleur, Shimano Ultegra
Saddle br_saddle, 11, 0, Saddle, Fabric Scoop
Seatpost br_seatpost, 11, 0, Seatpost, Cannondale THREE alloy
Shifter br_shifter, 11, 0, Shifter, Shimano Ultegra
Stem br_stem, 11, 0, Stem, Cannondale TWO alloy
Tyres br_tyres, 11, 0, Tyres, Vittoria Rubino Pro G2.0 30c
Wheels br_wheels, 11, 0, Wheels, Fulcrum Rapid Red 900