2025’s Top Endurance Bikes [Cannondale Synapse Carbon 3 L Review]

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Cannondale Synapse Carbon 3 L Review

• Price: $3000
• Frame: Synapse Carbon
• Tire Size: 30

What we like about it: Comfortable Geometry, Integrated Lighting, Versatility, Quality Components
What we didn’t like about it: Weight Considerations, Proprietary Features
Rating: (4.9/5)

Long distances covered with comfort, efficiency, and style define endurance cycling; the Cannondale Synapse Carbon 3 L wonderfully encapsulates these attributes. Built for riders who want extended hours on the saddle without sacrificing performance, this bike is meant to provide a flawless and steady ride. The Synapse Carbon 3 L delivers a ride unlike any other, whether your path is picturesque, mountainous, or endless pavement. We will explore in this study its characteristics, performance, and why it is among the best endurance bikes on the market nowadays.

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Riding Adventures

I rode the 100-mile endurance Cannondale Synapse Carbon 3 L to the Tour de Green Mountains in Vermont last weekend; this ride is renowned for its breathtaking scenery and difficult course. Starting in the little hamlet of Manchester, the event meandered across undulating hills, picturesque backroads, and rocky mountain passes.

The journey started on a cold morning; the first leg included newly paved roadways. The Synapse Carbon 3 L’s minimal weight carbon frame really caught my attention. Every pedal stroke seemed deliberate, and I picked my groove fast. As the group rode throughout shaded wooded areas, the SmartSense lighting system turned on to guarantee sight and safety on the meandering paths.

Climbing

About twenty miles in, we came upon Brandon Gap, among the route’s hardest climbs. The gradient grew gradually, with mixed smooth asphalt and fractured pavement and steep switchbacks. Using the Shimano 105 drivetrain, which responded well, I dropped into a lower gear. The endurance geometry of the bike let me keep power and be comfortable in the saddle.

I stood up to force more as the hill steepened. The SAVE micro-suspension absorbed road vibrations, therefore smoothing out the climb’s sensation. The Synapse felt steady and responsive even as my legs burnt, giving hope on every pedal stroke.

Going Down

The expansive vistas of Vermont’s Green Mountains at the summit astounded me. Still, the descent was yet to come—the finest part. Lean into the drops, then let the bike fly down the curving road. On severe hairpin turns as well, the hydraulic disc brakes provided exact stopping power. Perfect handling from the Synapse kept calm on uneven gravel areas and maintained speed on smoother sections.

The last leg wound down the gorgeous Otter Creek on level roads surrounded by beautiful farms and mild slopes. After eighty kilometers, I started to feel tired; yet, the Synapse’s comfy saddle and endurance geometry kept me going. Under me the bike seemed light, flowing over minor road flaws with ease.

Smiling when I crossed the Manchester finish line was natural. The Cannondale Synapse Carbon 3 L handled flats, hills, descents, and runs with great ease. It proved it’s the ideal friend for endurance riders looking for performance and comfort since it turned the difficulty of the Green Mountains into an amazing adventure.

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Specialized Features

The Cannondale Synapse Carbon 3 L boasts a lightweight carbon frame and fork ideal for endurance riding. Its proportional response shape is customized to fit various frame sizes, guaranteeing that every rider rides in comfort and balance. For long distances and climbs, the carbon design of the frame lowers weight while preserving rigidity, increasing efficiency.

The SmartSense system—which combines front and rear lighting into the bike’s architecture—stands out as one particularly remarkable element. Particularly on trips early in the morning or late evening, these lights improve safety and visibility. A central battery drives the system, saving the need for several chargers and guaranteeing rider convenience.

The bike boasts a consistent Shimano 105 12-speed transmission. This groupset lets riders easily handle steep climbs and quick descents by offering smooth, exact shifting. The Synapse Carbon 3 L is a flexible choice for endurance riders since its large spectrum of gears guarantees adaptation on any terrain.

The Shimano 105 hydraulic disc brakes produce constant, strong stopping force for braking performance. These brakes, which run effectively in any weather, provide riders confidence during descents or unexpected stops when coupled with 160mm rotors.

The wheelset comprises Vittoria Rubino Pro tires on WTB ST i23 rims. With enough grip to manage both smooth asphalt and light gravel, this combo provides an excellent mix of speed and endurance. Wider tires made possible by the tire clearance provide flexibility depending on the state of the road.

The Synapse boasts a carbon seatpost to assist absorb road vibrations, improving rider comfort. This guarantees that extended rides stay comfortable, even on worse roads, together with the endurance-oriented shape. The handlebars are made with ergonomics in mind to offer a relaxing riding posture free of compromise of control.

Built for endurance cyclists looking for a lightweight, comfortable, and dependable bike for daily training or long-distance events, the Cannondale Synapse Carbon 3 L is overall a standout choice.

Video

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Different Approaches

Comprising an ultra-lightweight HMX SL carbon frame and fork for optimal performance, the Addict Gravel Tuned marks the height of the series. Its top-of-the-line SRAM Red eTap AXS 24-speed electronic drivetrain provides unmatched shifting accuracy. Superior modulation and stopping force come from the hydraulic disc brakes. This model is meant for fierce rivals and riders that want the very best in gravel biking technologies.

Every one of these models fits particular riding inclinations, and the Scott Addict Gravel line guarantees a good choice for a broad spectrum of gravel riding aficionados.

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Benefits

• Comfortable Design: Long-distance riders would find the endurance-oriented design suitable for a comfortable riding posture.
• SmartSense Integrated Lighting System: Improves road view to others, increasing safety.
• Versatility: Able to fit up to 35mm tires, letting riders adapt to different road conditions and tastes.
• Reliable Components: The Shimano 105 groupset and hydraulic disc brakes are well-known for their dependability and performance, providing confidence over varied terrain.

Disadvantages

• Weight: Though the carbon frame is lightweight, some riders may perceive the overall weight of the bike, affected by components like wheels, to be somewhat greater than other models in its class.
• Proprietary Features: Some proprietary elements, like the SmartSense system, could make customizing or replacement with outside parts difficult.

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FAQ

1. The Scott Addict Gravel 20 is most suited for what kind of terrain?
   On gravel paths, uneven trails, and asphalt roads among other terrains, the Scott Addict Gravel 20 shines. Its SRAM Rival eTap AXS drivetrain, wide 700x45C tires, and lightweight carbon frame make it flexible enough for mixed-surface excursions, gravel races, and long-distance endurance rides.
2. In what ways may the electric drivetrain enhance the riding experience?
   Perfect and flawless shifting is offered by the SRAM Rival eTap AXS 24-speed electronic drivetrain. It lets riders move naturally between gears—even on difficult descents or high hills. The wireless configuration guarantees constant performance under all conditions and lowers maintenance.
3. Are long-distance rides comfortable on the Scott Addict Gravel 20?
   Indeed, comfort and endurance were considered in the design for the bike. Although its HMF carbon frame absorbs road vibrations, its reduced seat stays and carbon seatpost improve comfort even more. Even on uneven gravel conditions, the Schwalbe G-One Bite Performance tires and stable design offer a smooth and under-control ride.

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Spec

Category	Details
Platform	Synapse Carbon
Model Name	Synapse Carbon 3 L
Model Code	C12303U
Frame	Synapse Carbon, SmartSense equipped, Proportional Response size-specific design, BSA threaded BB, flat mount brake, 12x142mm thru-axle, thru-tube internal cable routing with Switch Plate, removable fender bridge, hidden rack/fender mounts
Fork	Synapse Carbon, integrated crown race, Proportional Response size-specific design, 12x100mm thru-axle, thru-tube internal routing, hidden fender mounts
Headset	Synapse Sealed Bearing, integrated, 1-1/4″-1-1/8″
Rear Derailleur	Shimano 105 7100, 12-speed
Front Derailleur	Shimano 105 7100, braze-on
Shifters	Shimano 105 7100, 12-speed
Chain	Shimano 105 7100, 12-speed
Crank	Shimano RS520, 50/34
Rear Cogs	Shimano 105 7100, 12-speed, 11-34
Bottom Bracket	Shimano BSA
Brakes	Shimano 105 7170 hydraulic disc, 160/160 RT70 rotors
Brake Levers	Shimano 105 7100, 12-speed
Rims	RD 2.1, 28h, 21mm inner width
Spokes	Stainless Steel, 14g
Tire Size	30
Wheel Size	700
Hubs	(F) Formula cartridge bearing, 12x100mm centerlock / (R) Formula cartridge bearing, 12x142mm centerlock
Tires	Vittoria Zaffiro Pro Reflective, 700x30c
Handlebar	Cannondale 3, 6061 Alloy, Compact
Stem	Cannondale 3, 6061 Alloy, 31.8, 7°
Grips	Fabric Knurl Bar Tape
Saddle	Fizik Aliante Delta, S-alloy rails
Seatpost	Cannondale 3 SmartSense, 6061 Alloy, 27.2x350mm (48-56), 400mm (58-61)
Wheel Sensor	Cannondale Wheel Sensor
Extra 1	SmartSense with Lights, Trainer-compatible thru-axle
Safety Information	WARNING – INGESTION HAZARD: This product contains a button cell or coin battery. DEATH or serious injury can occur if ingested. Keep new and used batteries OUT OF REACH OF CHILDREN.

Table of Comparisons

Bicycles	Price	Kits	Gear	Power Meters	Wheels	Frame
Specialized Roubaix	$4,500	Shimano Ultegra	2×11 Electronic	Not Included	700c Carbon	Carbon
Trek Domane SL 6	$4,200	Shimano 105	2×11 Mechanical	Not Included	700c Carbon	Carbon
Giant Defy Advanced 2	$3,800	Shimano GRX	2×11 Mechanical	Not Included	700c Carbon	Composite

Cannondale Synapse Carbon 3 L VS Specialized Roubaix

Renowned for its comfort-oriented design, the Specialized Roubaix uses the Future Shock suspension system to absorb road vibrations, therefore smoothing down the ride over great distances. Its sensitive and low weight carbon frame guarantees effective power transfer. Its Shimano Ultegra groupset provides accurate shifting and dependable performance. The Roubaix also shows clearance for wider tires, hence improving comfort and stability on different road surfaces. Some riders, nevertheless, could find the Future Shock system complicates maintenance.

Cannondale Synapse Carbon 3 L VS Trek Domain

With an IsoSpeed decoupler that lets the seat tube flex, mitigating shocks and lowering rider fatigue, the Trek Domane stresses endurance and adaptability. Its shape fits for extended rides and its carbon frame is designed for both comfort and acceleration. The Domane offers dependable shifting capability with a Shimano 105 groupset. It also features plenty of tire clearance for bigger tires and disc brakes for assured stopping capability, so enabling different terrains. One possible disadvantage is that riders looking for a more aggressive riding posture could find the laid-back shape unappealing.

Cannondale Synapse Carbon 3 L VS Mega Defy Advanced

Made for endurance riding, the Giant Defy Advanced boasts a carbon composite frame that strikes a mix of rigidity and suppleness. Its D-Fuse seatpost and handlebar mechanism combined helps to reduce vibrations, so improving comfort on longer rides. Having a Shimano Ultegra group set guarantees accurate and seamless shifting. For dependable stopping power, the Defy Advanced additionally provides disc brakes; for enhanced traction and comfort, it accommodates bigger tires. For certain riders, nevertheless, the integrated seatpost design could restrict adjustment.

Final Thought

Masterwork in endurance bike design is the Cannondale Synapse Carbon 3 L. For those who appreciate comfort and performance, its lightweight carbon frame, clever SmartSense technology, and rider-oriented geometry set it apart. This bike will improve your experience whether you’re practicing for a century cycle or you’re exploring new roads. The Synapse Carbon 3 L is an investment worth making for endurance aficionados searching for a dependable and effective partner. Prepare to ride your lengthy distances to the next degree!