MERIDA REACTO 2025 vs CERVELO S5 2025 comparison test review advantages disadvantages problems performance opinions reviews everything you need to know (really)
Aero Faceoff 2025: Merida Reacto vs Cervélo S5 - The Ultimate Guide
2025 sees the battle between two of the most sought-after aero bikes on the market: the Merida Reacto and the Cervélo S5. Both promise speed, efficiency and cutting-edge design, but they have distinct philosophies and features. This in-depth comparison guide dives into every aspect of these two contenders, drawing on tests, expert reviews and rider opinions to give you everything you (really) need to know to make the right choice.
Philosophy and Design
Merida Reacto 2025: The latest iteration of the Reacto further evolves its aero design, integrating WIRE PORT cable routing for a clean aesthetic and an optimized aerodynamic advantage. Merida focuses on a balance between aerodynamics, lightness and surprisingly good comfort for a bike in this category, thanks to the proven S-FLEX seatpost. Its geometry aims to compromise between racing aggression and usability over long distances.
Cervélo S5 2025: The S5 has always been synonymous with advanced aerodynamics. Its frame design, with radical shapes and extreme integration of each component (handlebar, stem, cable routing), is designed to cut through the air with the least possible resistance. Cervélo aims uncompromisingly for maximum speed and stiffness, favoring pure performance on the asphalt. Its geometry is typically more aggressive and oriented towards competition.
Aerodynamic Performance
Both bikes are designed to minimize aerodynamic resistance, but with different approaches:
Merida Reacto 2025: Optimized frame shapes, cable integration and airfoil tubes contribute to remarkable aerodynamic efficiency. Tests show a significant gain compared to previous generations, making it one of the fastest bikes in its category.
Cervélo S5 2025: Total component integration and extremely aerodynamic frame shapes put the S5 at the top of the class in terms of air penetration. Every detail is designed to reduce drag, making it a speed machine on the flats and in the sprints.
Opinions and Reviews: Experts agree that both bikes offer a significant aerodynamic advantage over non-aero models. The S5 may have a slight advantage in high-speed and pure flat conditions, while the Reacto may offer better balance in different situations thanks to its superior comfort.
Weight and Stiffness
Merida Reacto 2025: Merida has worked to keep the weight down without sacrificing stiffness. The carbon frame is light and reactive, offering good power transmission on climbs and in sprints.
Cervélo S5 2025: The S5 focuses on maximum stiffness for loss-free power transmission, essential for speed. It may be slightly heavier than the Reacto, due to its greater integration and beefier shapes.
Opinions and Reviews: The Reacto is often praised for its good compromise between stiffness and a competitive weight. The S5 excels in torsional stiffness, offering a very responsive feel, but it may feel a little less agile on climbs than the Reacto due to its potentially higher weight.
Comfort
Merida Reacto 2025: Thanks to its S-FLEX seatpost and the ability to run up to 30mm of tires, the Reacto offers a surprising level of comfort for an aero bike. This also makes it more suitable for long distances and less than perfectly smooth roads.
Cervélo S5 2025: Comfort is not the main priority of the S5. Its extreme stiffness and aggressive geometry make it less forgiving on long rides or on rough roads. Wheel and tire choice plays a crucial role in improving (or degrading) comfort.
Reviews & Opinions: Most testers agree that the Reacto offers more comfort than the S5, making it a more versatile choice for a variety of rides. The S5 is more geared towards short, fast races or rides where pure performance is the primary goal.
Handling
Merida Reacto 2025: The Reacto offers precise and predictable handling, suitable for both fast corners and sharp changes of direction. Its balance makes it intuitive to ride.
Cervélo S5 2025: The S5's handling is often described as very direct and responsive, thanks to its stiffness. However, it requires a more "active" ride and may be less forgiving if you make mistakes in setting up the curve, especially on rough or wet surfaces.
Reviews & Opinions: The Reacto is generally considered easier and more intuitive to ride for a wide range of riders. The S5, with its extreme responsiveness, might be preferred by experienced runners looking for a surgical precision in the handling.
Components and Builds
Both bikes are available in a variety of builds, with Shimano (Ultegra, Dura-Ace), SRAM (Force, Red) groupsets and high-end wheels (often carbon). The build you choose will significantly impact the price and performance.
Key Points:
Merida Reacto 2025: Often offers excellent value for money in the mid-range builds, with performance components at a competitive cost.
Cervélo S5 2025: Tends to be positioned in the higher price range, with premium builds that reflect its racing vocation.
Brakes
Both bikes are equipped with hydraulic disc brakes, which provide excellent and modulable stopping power in all weather conditions. The rotor sizes (often 160mm front and rear) are standard for modern racing bikes.
Pros and Cons
Merida Reacto 2025:
Pros: Great aerodynamics, good comfort for an aero bike, competitive weight, intuitive handling, often better value for money.
Cons: Aerodynamics potentially not as good as the S5 in specific conditions, less radical aesthetics for some.
Cervélo S5 2025:
Pros: Best-in-class aerodynamics, exceptional stiffness for maximum power transmission, aggressive and distinctive aesthetics.
Cons: Limited comfort, handling requires more experience, generally higher price.
Known Issues
Because they are relatively new models, there are no chronic issues with either bike. However, as with any product, isolated manufacturing defects may occur. It is always advisable to buy from a reputable dealer and inspect the bike carefully when purchasing.
Performance
Merida Reacto 2025: It excels in sprints, on flats and holds its own on climbs thanks to its good weight/stiffness ratio. Its comfort also makes it suitable for long rides and races on mixed routes.
Cervélo S5 2025: It is a speed machine on flats and in sprints, where its aerodynamics make the difference. Its stiffness makes it reactive in sprints, but its limited comfort makes it less ideal for long distances or challenging climbs for some cyclists.
Final Opinions and Reviews
The choice between the Merida Reacto 2025 and the Cervélo S5 2025 depends on your priorities as a cyclist:
Choose the Merida Reacto if: You are looking for an excellent aerodynamic bike with a good compromise between speed, comfort and handling, perhaps with an eye on the quality-price ratio and versatility for different types of routes.
Choose the Cervélo S5 if: Maximum speed and uncompromising aerodynamics are your top priority, you are an experienced rider looking for a highly responsive bike for flats and sprints, and comfort over long distances is not your main concern.
All you (really) need to know is that there is no absolute "better". Both are top-tier bikes, designed to excel in specific areas. Carefully consider your needs, your riding style and the type of routes you ride most often to make the choice that will give you the most satisfaction. A test ride of both bikes, if possible, would be ideal to form a personal and definitive opinion.