Felix's appetite for epic rides has grown, so the endurance-focused Synapse seems like the perfect companion
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The Synapse sits firmly in the endurance road bike category, but Cannondale says it differs from its other road bikes thanks to its ride characteristics, which are focused more around rider comfort than flat-out speed.
The Synapse is available in three different frame versions ranging from the cheaper aluminium model to a standard carbon frame, and then a Hi-Mod version which has a higher strength to weight ratio. I’m testing the mid-range Carbon Synapse Disc Ultegra model.
It would be fair to say that I’ve got a keen interest in gravel riding, which is lucky because, arguably, bikes designed for endurance have started merging with their gravel counterparts.
The Synapse is no exception, and with tyre clearance up to 32mm and its shock-absorbing SAVE tech, it’s clearly been designed to take on gravel roads, such as those found in ultra-endurance races such as the Transcontinental.
I plan to test it out on mixed surfaces and some big miles on tarmac over the course of the year to see how it handles the different terrain.
Cannondale Synapse Disc Ultegra long-term review update two
The Synapse is a real joy to ride in these times, despite shorter outings.Felix Smith
I’ve not made any significant changes to the Synapse for this update because the last few weeks have been all about managing my on-going left and right knee troubles.
I have lowered the bar height a touch, replaced the Fabric Scoop saddle with a Specialized Mimic and made a slight change in saddle angle, though.
However, what remains the same is the Synapse’s amazing handling and comfort that’s impressed me since I began testing it in February. But I do have some pretty exciting upgrades planned for my next update, so stay tuned for that.
I found the stock Fabric Scoop lacking in comfort and a little harsh over bumps, I always struggled to get truly comfortable. So, after searching for some time for a saddle better suited to my needs, I settled on Specialized’s Mimic, which is an evolution of the well-known Power saddle.
Bear in mind, saddle comfort is extremely personal, but after around 800km on the Scoop it won’t be a saddle I go back to using.
Since my rides haven’t been particularly long or far from home during the global pandemic, the extra comfort I’ve had from the relatively tall front-end hasn’t been worth the, albeit probably small, aerodynamic disadvantage.
As a result, I have dropped the bar height by another 10mm since the last update and feel the bars are now in a more natural position. The ride feels considerably more sporty when compared to the initial setup.
In the future, should I want to add aero extensions for longer, multi-day rides, I’d set these a minimum of 20mm higher than the current position of the handlebars. Although hard to say without setting up, I believe this could give me a good compromise between comfort and aero advantage.
After making the bar height change, I felt myself ending up on the nose of the saddle, especially during harder efforts. So I’ve tilted the saddle nose up by a few degrees to help me find a more sustainable position, not forgetting to lower the seatpost by a few millimetres to compensate.
Dropping the stem by another 10mm has given me a more neutral riding position.Felix Smith
Reversing long-term knee damage is a notoriously difficult job and, having had a great spell of rehabilitation with a period of pain-free riding, I fell back to the knee niggles that had previously dominated my rides. It came at the peak of my latest build up in fitness, when presumably I overcooked it.
That brief experience of pain-free riding felt so good and I’m determined to not push too hard too early again, so here goes a chilled-out summer of riding where my knee rehab comes before my fitness.
I’m going to focus on looking after my body rather than riding hard for the time being.Max Wilman
I’ve been combining my rides with a dedicated stretching plan since January 2020 and focusing on areas of chronic tightness, with some strengthening exercises too.
Metering my imbalance
For a while now, I’ve noticed my right leg is working much harder than the left. Over time this has resulted in quite a big imbalance in my body and although I can’t quantify the difference yet, I believe it must be having an impact on my knees.
So, for now, I will continue the strengthening exercises to try and address the balance issue and see how they help my rehab.
Of course, a double-sided power meter, such as on a set of Garmin Vector pedals, would allow me to quantify how much of an imbalance is present and track the difference in power between my legs over time. Perhaps this is a test for a future update.
Older updates continue below.
Cannondale Synapse Disc Ultegra long-term review update one
Due to the pandemic and everything that goes with it, I haven’t been able to ride much longer than a few hours at a time, which of course means I’m not really able to find out how the bike fares over longer distances.
Having said that, I am currently working through a knee injury which has plagued me on and off for a few years, so, for now, shorter and less intense solo rides combined with a rigorous twice a day stretching routine are really helping me to overcome my knee niggles.
The bike has done a fantastic job of keeping my spirits high though, and the frame’s compliance still impresses me whenever I ride over lumpy roads.
Cannondale’s SAVE frame technology still surprises me with its road buzz reducing design.Felix Smith
I’ve spent some time upgrading and optimising the bike for my needs too, which has been fun.
Unintentional weight savings
Although the Cannondale Three series bar and stem were both fine for the job, and their simple design and subtle graphics were decent looking, they were the first part to be swapped out.
Fizik Cyrano 00 carbon handlebars are a rather lavish upgrade.Felix Smith
I chose to put on the beautiful and superlight Fizik Cyrano 00 handlebars. These were used on BikeRadar video manager Joe Norledge’s hill climb bike a few seasons ago.
The bars weigh just 182g, but it is not my intention to create a weight-weenie Synapse, instead they’re just really cool and a nice upgrade over the specced parts.
The Fizik bars are categorised according to their dimensions and flexibility of the rider. These bars sit in the middle of the sizing range and are named the Chameleon, combining a long reach with fairly compact drops for riders with middling flexibility.
The Fizik R1 stem finishes the cockpit off nicely. A torque wrench is recommended!Felix Smith
As for the stem, I couldn’t stand mismatching brands so I picked up a Fizik Cyrano R1 stem for a bargain price on eBay.
It retains the stock stem’s 100mm length and +/- 7-degree angle, but again it’s lighter and since I’ll be looking down at the cockpit a fair bit over the course of the year, it makes me happy.
Like I said before, weight is not my overriding concern for this endurance-focused bike, but changing these two parts saved 145g.
Swapping the bars meant I could change the bar tape, too. I really like Enve’s 3mm thick tape because it has a nice soft yet grippy texture that’s perfect for an endurance bike.
I wasn’t immediately enamoured with its grey colour, but I have to say it has grown on me.
The SON Delux dynamo front hub offers minimal resistance.Felix Smith
The stock Fulcrum 600DB wheels were one part I really wanted to change on the bike, so I could run a dynamo on the front wheel.
I’ve fitted a Hunt Superdura Dynamo front wheel set up with the ever-dependable Exposure Revo front light and Exposure Red Eye on the rear. To secure the wiring to the frame, I’ve gone with the slightly inelegant solution of good old electrical tape.
I have used this in the past for dynamo lighting and haven’t had any issues, so I have faith in the tape!
This GPS mount from JRC Components allowed me to get my controls centrally aligned and without cluttering the bars.Felix Smith
The bling GPS mount from JRC Components that’s bolted onto the lower stem mounts has allowed me to mount the Exposure Revo front light at the same time, thanks to the extra-long bolts and spacers supplied with the mount.
This has given the bike a satisfyingly minimalist cockpit, although it’s a shame about the messy cables, which I still can’t help but focus on.
Although light and well built, these are not gravel wheels.Felix Smith
I swapped the rear wheel for a carbon-rimmed Fast Forward F3 Disc. The rim is built onto a DT Swiss 240s straight-pull hub that’s well known for its simple and easy to service ratchet system freehub, which produces a subdued but deep purr when you freewheel.
There are a number of downsides to the Fast Forward F3 Disc wheel.
First up, it is not tubeless compatible and because I am a tubeless convert and have got used to the lack of punctures and lower pressures you can achieve with the system, this can be a bit frustrating.
The rim is also narrower than more modern tubeless rims, which means the tyre is noticeably narrower compared to the Hunt Superdura rim up front, although the Superdura rim is fairly wide at 20mm internal width.
Hard(er) core credentials
No creaks or squeaks just yet from Cannondale’s BB30 bottom bracket.Felix Smith
Because the Synapse has confident handling on mixed surfaces, I’ve taken the bike up and down a small local gravel trail, hopping over small drainage ditches.
While this is great fun, the F3D rear wheel buckled slightly, suggesting it wasn’t built quite well enough to withstand riding at the more adventurous end of the spectrum.
Upgrading the tyres from the Vittoria Rubino Pros to a pair of 28mm Continental GP5000 TL tyres was a worthwhile change, but obviously I’m currently only able to run the front tubeless.
Continental GP5000 TL tyres offer great grip and rolling resistance, but time will tell for their durability and tubeless reliability.Felix Smith
The Continentals are known to be some of the best performing tyres on the market and I think they balance grip and speed very well. Because the Cannondale is such a fun bike to throw around a corner, these tyres are a great match for it.
Should I fancy pushing the Synapse further, away from the road, the tubeless version is also available in a 32mm.
In my initial review (below), I mentioned the Shimano brake levers felt a little unnerving when descending on the hoods.
I’m really getting on with the shape of the Shimano Ultegra hydraulic brake hoods.Felix Smith
After a few months of riding I feel much more poised, getting used to how the levers move, and with the Ultegra brakes being properly powerful, my confidence has returned.
Unfortunately, I haven’t really been able to test out the endurance abilities of this bike, but it continues to be seriously fun to ride.
At the time of writing, I intend to keep riding regularly not only to help with my wellbeing but also the rehabilitation of my knee, which I’m hoping will get better and stronger as the year progresses.
The original story continues below.
Cannondale Synapse Disc Ultegra specifications and details
The frame’s lines remind me of sinews with a kind of refined, muscular look, but without being overly aggressive.Felix Smith
My 54cm Carbon Ultegra model is painted in the blazingly bright orange “crush” colour, but it’s available in black if you want something more inconspicuous.
There are many different spec levels to choose from but this mid-range Ultegra model weighs in at 8.89kg without pedals.
The frame and fork use BallisTec in their carbon layup process, supposedly taken from military ballistic armour, which is claimed to create a super-tough material.
The frame features Cannondale’s SAVE PLUS technology, which it says creates vertical compliance for comfort without sacrificing lateral and torsional stiffness for speed and efficiency. This is most noticeable in the helix-shaped seatstays that bend and compress under load.
The Ultegra-spec parts certainly look the part.Felix Smith
The drivetrain is mostly made up of Ultegra parts, including the front and rear derailleur, and the hydraulic brakes and the levers.
The 11-34t cassette is Shimano’s 105 version, however – presumably to save some money.
Since the frame is based around Cannondale’s own BB30a bottom bracket platform, it’s specced with a Cannondale 1 crankset with 50/34-tooth FSA chainrings.
The Shimano Ultegra GS rear mech does a lovely job of shifting the chain up and down and doesn’t find it difficult to reach the 34-tooth rear sprocket.Felix Smith
The seatpost, stem and handlebar are all from the Cannondale Three range, and the seatpost measures 25.4mm in diameter, matching that of higher-end carbon models.
There’s a Fabric Scoop Shallow Sport saddle with steel rails and nice, chunky 3.5mm Cannondale Grip bar tape with gel to round off the contact points.
The Cannondale Three seatpost has a very narrow 25.4mm diameter to help reduce road buzz.Felix Smith
Equipped with Fulcrum Racing 600DB wheels with Centerlock hubs and 12mm quick release thru-axles both front and rear, the rims are tubeless compatible, although the Vittoria Rubino Pro 30mm tyres are not. They do incorporate graphene in their triple compound however, so that’s a bonus.
The Cannondale Three 100mm stem is plain, but not in a bad way.Felix Smith
Cannondale’s claims of the Synapse being a true endurance-focused bike are reflected in its geometry.
It has a tall 570mm stack height, giving a classic upright position – Cannondale’s gravel bike, the Topstone, has a similar measurement of 579mm – which suggests the Synapse could make a fun gravel bike, too.
At 410mm, the chainstays are relatively short, which should give the bike snappy handling, especially in the corners. It will mean it’s perhaps not as planted and stable at higher speeds or when descending on gravel, though.
A bottom bracket height of 272mm isn’t radical but should help get a relatively low centre of gravity for controlled cornering. For comparison, the Topstone Carbon is 280mm and the Cannondale SuperSix EVO is 271mm on a 54cm frame size.
Head angle: 71.7 degrees
Seat angle: 73.9 degrees
Seat tube: 480mm
Top tube: 547mm
Head tube: 161mm
Bottom bracket height: 272mm
Why did I choose this bike?
Removing the seatpost collar not only improves compliance but also looks clean and uncluttered.Felix Smith
The Cannondale Synapse is not designed for sprint finishes, nor is it a bike built for pure climbing. What it claims to do best is provide a comfortable place to pedal all day and all night, if that’s your jam, and not be confined to just tarmac yet still be agile and able to handle speed.
As a rider that enjoys riding longer distances, and is never going to be finishing in the top 10 in a hill climb or road race, I appreciate these qualities. Choosing the Synapse to ride over the coming year seemed like a sensible option and I’m interested to see if the bump-smoothing technology on the bike will give me the edge after multiple hours riding.
Thanks to my fortunate position as a videographer on BikeRadar‘s YouTube channel, this is the first time I’m going to ‘own’ a road-specific bike for a longer period of time.
Cannondale suggests a maximum of 32mm tyres for the Synapse – perhaps the bike’s most limiting factor when it comes to gravel riding.Felix Smith
Certain features on the Synapse, such as clearance for 32mm tyres, aren’t a far cry from the adventure style bikes I have ridden in the past and I’m curious to see how it will blend its obvious road intentions with its ability to ride off-road.
If it lives up to the claims of taking on “wilder” riding then this could actually be a very capable and quick bike.
Cannondale Synapse Disc Ultegra initial setup
At 177cm tall, I opted for the 54cm, as instructed by Cannondale.
To get the bike set up initially, there were no proprietary fittings to worry about.
It is a shame the tyres aren’t tubeless compatible.Felix Smith
I adjusted the brake lever reach so that it was closer to the bars and pumped the Vittoria Rubino Pro tyres to 55psi, a relatively low pressure given their 30mm width.
However, they aren’t tubeless, so taking care to avoid potholes is still important.
The Fabric Scoop Shallow Sport saddle with steel rails — only time will tell if it suites my derrière.Felix Smith
The Fabric Scoop saddle is relatively long, especially compared to the Specialized Power saddle I have ridden in the past.
I moved it rearward in the rails after the first ride because I felt a little too forward of the pedals, and lowered the seatpost slightly to compensate for this.
The seatpost is held in place by a wedge that’s well below the top tube, creating more flex and more comfort.Felix Smith
The seatpost clamp is hidden underneath the top tube and sits quite deep into the frame, which means some short Allen keys might struggle to reach the bolt.
Cannondale Synapse Disc Ultegra ride impressions
Shorter chainstays make for quick handling and fun descending.Max Wilman
On the first ride, I instantly noticed the tall stack height and super-smooth feel over cobbles and imperfections in the road. It was also incredibly quiet both in terms of freehub noise and general chatter.
It felt very responsive when cornering. Tight bends are enjoyable and, on my first ride, I found myself turning a little sharper than I was expecting.
A few corners later, I quickly got used to the feeling, which, together with the frame’s compliance, makes for a fun yet very smooth riding experience.
The oversized bottom bracket helps to deliver smooth and efficient power transfer into the drivetrain.Max Wilman
I noticed right away that the tubed Vittoria Rubino Pro tyres held the bike back a little and I feel the ride would be enhanced with the ability to run lower pressures afforded by tubeless setups.
But I did feel at home pretty quickly when descending, attributing this to the frame’s road-smoothing SAVE technology.
DoubleTap habits die hard
I found the movement of the Shimano Ultegra brake levers slightly unnerving at first.
Shimano levers require an inward shift stroke to change gear, and being used to SRAM’s DoubleTap levers I’ve developed a habit of using the rigidity of the lever for stability, so when braking with Shimano I find the lever pushes to the side slightly, which doesn’t provide me with confidence when descending.
Hopefully I can get over this!
The Ultegra hydraulic disc brakes do a superb job, though, and straight away felt very dependable, allowing me to brake later than I usually would.
I haven’t noticed any excessive noise from them yet, although I’ve not ridden them in the city, which, when it’s raining, seems to be a sure way to contaminate the pads and rotors.
160mm rotors and Ultegra hydraulic calipers make for seriously controlled braking.Felix Smith
After a couple of initial rides to help setup the bike, I felt a small amount of play from the front end.
This felt very much like the headset was loose, but after a bit of tinkering I realised the movement was actually coming from the brake rotor.
The Shimano Centerlock RT30 rotors were torqued to the recommended amount, but, despite this, with the front brake and some force applied forwards and backwards, the rotor was able to move a small amount.
The Cannondale Three handlebars with thick and grippy 3.5mm Grip bar tape are perfect for long rides.Felix Smith
The 3.5mm Cannondale Grip bar tape with gel is a great addition to the bike and not only adds a lot of comfort but feels nice and grippy, too. This is an important component of an endurance bike and an area that could have been overlooked.
BB30 problems? Not yet!
Climbing on the Synapse is helped by the oversized BB30a bottom bracket. The original form of this bottom bracket was adopted by Cannondale back in 2000, and adding stiffness to the frame is its biggest plus.
When climbing out the saddle I really felt the bike transferring my power efficiently and, unsurprisingly, it feels wonderfully smooth.
I felt the oversized bottom bracket helped to deliver smooth and efficient power transfer into the drivetrain.Max Wilman
I’ve seen reports of BB30a bottom brackets developing noises over time, so it’ll be interesting to see how I get on.
It’s a looker
I really like how the Synapse looks and the frame’s lines remind me of sinews, with a kind of refined, muscular look that isn’t overly aggressive.
I particularly like the split in the seat tube as it meets the bottom bracket shell.
The beautifully clean and smooth frame is spoilt by the mess of cables upfront.Felix Smith
Although it does have internal cable routing, the brake and gear cables look messy at the front of the bike. This does spoil the otherwise handsome appearance and, although not necessarily important to some, probably doesn’t enhance its aerodynamic properties.
I’ve also found it difficult to mount a compact handlebar bag since the outer cables get in the way.
At just shy of 9kg and with a price tag of £2,700 some might expect it to weigh less. However, it is important to remember that this is a bike designed for going the distance in relative comfort, rather than being optimised for short, full-on efforts.
It hasn’t been designed with aerodynamics at front of mind, either, but since ultra-distance racing is taking off around the world could be the next step for the Synapse range.
If you’re racing thousands of kilometres, an aero advantage seems like an obvious consideration, but for me, comfort, conditioning and rehabilitation of my knee are all more important than all-out speed this year.
Cannondale Synapse Disc Ultegra upgrades
The first things I bolted on were the Lezyne Flow side-loading bottle cages.Felix Smith
Before I had taken the Synapse for a proper ride I installed two Lezyne Flow side-loading bottle cages.
These have to be my favourite bottle cages because I can use a top-tube style frame pack and still get bottles in and out. They are super-light but tough and, despite the side loading design, I have never lost a bottle, even when gravel racing.
The areas where I can see meaningful upgrades made are the wheels and tyres.
The Fulcrum Racing 600DB wheels aren’t bad; they are tubeless-ready, have sealed cartridge bearings and durable brass nipples. However, the internal width of 17mm isn’t very wide for a bike that comes with 30mm tyres as standard and, at 1,690g for the pair, they aren’t particularly light for a bike that costs £2,700.
The Fulcrum Centerlock hubs have sealed cartridge bearings.Felix Smith
Upgrading the wheels to something with a wider profile and lower weight would be an easy performance win. I’d be interested in some deeper section aero rims too for long-distance rides because there could be significant aerodynamic gains to be had.
At 30mm, the Rubino Pro tyres are a good width for taking the edge off poor road surfaces, but since they aren’t tubeless compatible, the performance gains of a modern wide tyre cannot be fully taken advantage.
I’d like to try a fast tubeless tyre like the Schwalbe Pro One or the Continental GP5000 in 28mm or 32mm widths. This would allow me to run lower pressures and also reduce the likelihood of punctures.
During winter, I was using the Hunt Superdura Dynamo Disc wheel to power an Exposure Revo front light and Redeye rear light. I used this setup for the 2,000km Transatlantic Way ride I attempted in 2019. I was absolutely converted to the dynamo. Having guaranteed lighting not only increases safety on the road but also means I have a bike that will always be ready for a ride no matter what the conditions outside.
The SON Delux hub is claimed to have 20 per cent less resistance than its standard dynamo hubs and, at around 400g, the weight penalty is virtually non-existent when compared to a non-dynamo setup requiring batteries for lights.
The Superdura rim has a super-wide 20mm internal width meaning tyres have a larger surface area for more grip and in some cases more speed. I believe this would be the perfect match for the Synapse and I’m really looking forward to getting it set up.
The Fabric Scoop saddle has generally good reviews from riders, so I plan to stick with it for longer rides to see how it feels. Saddles can take some time to get a feel for, and even though I am tempted to put on my Specialized Mimic saddle, I will hold off for now.
I instantly got on well with the mechanical Ultegra hydraulic brake hoods.Felix Smith
The Cannondale Three bar and stem are basic but functional and non-offensive to look at, but I have some Fizik Cyrano 00 bars kindly donated by BikeRadar‘s Joe Norledge that I’m planning to fit. They are extremely light at 180g and would give the bike a rather classy finish.
I also have some fairly controversial grey Enve bar tape, which I plan to wrap them in.
BikeRadar‘s 2020 long-term test bikes
At the start of the year, every member of the BikeRadar team selects a long-term test bike to ride over the course of the following 12 months. Some choose a bike from their favoured discipline and ride it hard for a year, others opt for a bike that takes them outside of their comfort zone.
Our long-term test gives us the opportunity to truly get to grips with these machines, so we can tell you how they perform through different seasons and on ever-changing terrain.
We also use them as test beds for the latest kit, chopping and changing parts to see what really makes the difference – and help you decide which upgrades are worth spending your money on.