Merida Reacto 4000 2026 - Road Bike
The Reacto 4000 combines aerodynamic efficiency with everyday rider comfort. A CF3 carbon frame, Shimano 105 12-speed groupset, and powerful hydraulic disc brakes make it a fast, well-balanced aero bike for racing or spirited rides.
Key Features
- CF3 IV carbon aero frame with race-proven geometry, Disc Cooler technology
- Reacto CF3 IV Disc full carbon fork
- Shimano 105 12-speed drivetrain with 52/36T chainset, 11–34T cassette
- Shimano 105 hydraulic disc brakes, 160mm rotors
- Merida Expert CW wheels with Continental Grand Prix 28mm tyres
- Integrated carbon seatpost with aero shaping
- Internal cable routing and clean aero design details
- Available with 0% APR finance
The Merida Reacto 4000 is designed to deliver speed, control, and efficiency, making it an excellent choice for riders entering road racing or wanting a high-performing aero bike. Built around a CF3 carbon frame, it shares the same aerodynamic shaping and geometry as Merida’s top-tier CF5, but with a more accessible carbon lay-up. The result is a frame that is both lightweight and stiff, with race-focused handling and aero features developed using Computational Fluid Dynamics (CFD) for real-world performance.
Comfort has been carefully built in. The Reacto 4000 accommodates up to 30mm tyres and comes equipped with Continental Grand Prix 28mm tyres, balancing speed with extra cushioning for longer rides. Merida’s Disc Cooler technology reduces brake temperatures by up to 35%, ensuring consistent braking power on long descents. The clean integration of the calipers within the frame further reduces drag while improving aesthetics.
The groupset is a full Shimano 105 R7100 12-speed system, offering precise and dependable shifting. A semi-compact 52/36T chainset paired with an 11–34T cassette gives you the range for flat-out efforts as well as hilly routes. Braking is handled by Shimano 105 hydraulic disc brakes with 160mm rotors, delivering controlled stopping power in all conditions.
Rolling on Merida Expert CW wheels with a 30mm depth, the Reacto 4000 strikes a balance between aero gains and stability in crosswinds. The wheels are fitted with Continental Grand Prix tyres for reliable grip and low rolling resistance. Merida’s aero-shaped Team CW carbon seatpost further complements the bike’s aerodynamic focus, while the inclusion of a Merida minitool adds practical utility.
Whether you’re pinning on a number for your first race, pushing the pace on club rides, or chasing your personal bests, the Reacto 4000 brings WorldTour-inspired aero technology into a package that’s both accessible and versatile. It’s a bike that proves you don’t need to compromise between speed, comfort, and control.
Occasionally, without notice, manufacturers change product design and/or specifications.
| Frame | CF3 IV - carbon with the same geometry and aeroydanmic profiling as the CF5 IV with a more budget friendly carbon lay up. Tapered headtube, Disc Cooler, BB86 BB standard,142 x12mm axle standard. Max tyre size 700 x 30c |
| Fork | Reacto CF3 IV Disc; material: carbon; 700x30C max. tyre size |
| Headset | Merida Team SL (OP-203 neck) |
| Stem | Merida Expert SL 2PII; material: aluminium; -9 degree rise; Length: (XXXS-XS) - 90mm, S - 100mm, (M-L) - 110mm, XL - 120mm |
| Bars | Merida Expert CW; material: aluminium; (XXXS-S) - 380mm wide, (M-L) - 400mm wide, XL - 420mm wide |
| Front Brake | Shimano 105; Hydraulic disc with Shimano RT54; 160mm |
| Rear Brake | Shimano 105; Hydraulic disc with Shimano RT54; 160mm |
| Brake Lever | Shimano 105 |
| Front Mech | Shimano 105 |
| Rear Mech | Shimano 105; GS |
| Shifters | Front: Shimano 105 disc, Rear: Shimano 105 disc |
| Speed | 24 |
| Rims | Merida Expert CW; 19mm inner rim width; 30mm rim depth |
| Front Hub | Shimano HB-TC500; 100x12mm; 28 Spoke; Centerlock |
| Rear Hub | Shimano FH-TC500-HL; 12-142mm; 28 Spoke; Centerlock |
| Spokes | Double Butted Black stainless |
| Front Tyre | Continental Grand Prix; 700x28C; kevlar bead |
| Rear Tyre | Continental Grand Prix; 700x28C; kevlar bead |
| Seat Post | Merida Team CW; Aero shape; 15mm layback; material: carbon |
| Saddle | Merida Expert SL; 6% recycled and 23% nature material; V-mount; incl. Merida minitool |
| Chainset | Shimano 105 R7100; 52-36 tooth chainset; Crank length: XXXS - 160mm, (XXS-XS) - 165mm, (S-M) - 170mm, (L-XL) - 172.5mm |
| Bottom Bracket | Shimano SM-BB71-41B; Pressfit 86.5 |
| Chain | Shimano M6100-12 |
| Cassette | Shimano 105 R7101; 11-34 teeth; 12 speed |
| Pedals | Not Included |
Merida Reacto Size Chart
| Size | Min Height cm | Max Height cm | Min height feet | Max height feet |
| XXS (47cm) | 153 | 162 | 5'0" | 5'4" |
| XS (50cm) | 162 | 168 | 5'4" | 5'6" |
| S (52cm) | 168 | 175 | 5'6" | 5'9" |
| M (54cm) | 175 | 181 | 5'9" | 5'11" |
| L (56cm) | 181 | 188 | 5'11" | 6'2" |
| XL (59cm) | 188 | 198 | 6'2" | 6'6" |
What size frame do I need if I am between sizes? - read here
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Merida Reacto 4000 2026 - Road Bike
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