The Merida Reacto 4000 is An aero road bike designed for speed and efficiency, the Reacto 4000 blends aerodynamic shaping with practical comfort. With a carbon frame, disc brakes and reliable Shimano 105, it’s ready for fast group rides and racing.
Key Features:
- CF3 carbon aero frame, lightweight build, race-focused geometry
- CF3 full carbon fork for precise handling
- Shimano 105 R7100 12-speed drivetrain
- Shimano 105 hydraulic disc brakes
- Merida Expert CW wheels with Continental GP 28c tyres
- S-Flex carbon aero seatpost for added comfort
- Available with 0% APR finance
The Merida Reacto 4000 brings high-end aero performance into a more accessible package, using the same aerodynamic frame profile found on top-tier models. The CF3 carbon frame is shaped to reduce drag while keeping weight low, helping you hold speed more efficiently whether you're riding solo or in a fast-moving group.
Comfort hasn’t been overlooked. Clearance for tyres up to 32mm gives you the option to run wider rubber for improved grip and reduced road buzz, while the S-Flex carbon seatpost is designed to introduce a degree of vertical compliance. This helps smooth out rough road surfaces without compromising the bike’s direct, responsive feel under power.
The Shimano 105 12-speed groupset offers dependable, precise shifting across a wide gear range, making it well suited to varied terrain. Paired with hydraulic disc brakes, you get consistent stopping power and control in all conditions, which is particularly useful on longer descents or wet rides.
Aerodynamic efficiency is at the core of the Reacto’s design. Tube shaping, internal cable routing and an integrated cockpit setup all work together to reduce drag while maintaining a clean, modern look. At the same time, the bike retains a balanced ride quality, making it suitable not just for racing, but also for longer training sessions.
Overall, the Reacto 4000 is a strong option if you’re looking for an aero road bike that delivers speed and efficiency, while still offering enough comfort and versatility for regular riding and progression.
Occasionally, without notice, manufacturers change product design and/or specifications.
| Frame | Reacto CF3 V; carbon; 700 x 32C max. tyre size; 100mm x 12mm / 142mm x 12mm axle standard; BB86. bottom bracket standard with disc cooler |
| Fork | Reacto CF3 V Disc; carbon; 700x32C max. wheel size |
| Headset | Merida Team SL (Cone RCT-608) |
| Stem | Merida Expert SL 2PII; aluminium; -9 degree rise |
| Bars | Merida Expert CW; aluminium; (3XS-S) - 380mm, (M-L) - 400mm, XL - 420mm |
| Front Brake | Shimano 105; Disc |
| Rear Brake | Shimano 105; Disc |
| 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; 30 HRI |
| Front Hub | Shimano TC500; 100x12mm; 28 spoke; Centerlock |
| Rear Hub | Shimano TC500-HL; 12-142mm; 28 spoke; Centerlock |
| Spokes | Double Butted Black stainless |
| Front Tyre | Continental Grand Prix; 700x28C; fold |
| Rear Tyre | Continental Grand Prix; 700x28C; fold |
| Seat Post | Merida Reacto V S-FLEX; Aero Shape; in-line; Carbon |
| Saddle | Akero RS PAS T2.0; V-mount adapter; incl. Merida minitool |
| Chainset | Shimano 105 R7100; 52-36 teeth; Crank Length: 3XS - 160mm, (XXS-XS) - 165mm, (S-M) - 170mm, (L-XL) - 172.5mm |
| Bottom Bracket | Shimano SM-BB71-41B; Pressfit 86.5mm |
| Chain | Shimano M6100-12 |
| Cassette | Shimano 105 R7101; 11-34 teeth; 12 speed |
Merida Reacto 2027 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
Merida Reacto 2027 Geometry Chart
|
Reacto V |
XXS |
XS |
S |
M |
L |
XL |
|
seat tube (mm) |
470 |
500 |
520 |
540 |
560 |
590 |
|
top tube horizontal (mm) |
521 |
535 |
545 |
560 |
575 |
590 |
|
head tube length (m) |
105 |
112 |
128 |
140 |
155 |
175 |
|
head tube angle () |
70.5 |
72 |
72.5 |
73.5 |
73.5 |
74 |
|
seat tube angle () |
74.5 |
74 |
74 |
73.5 |
73 |
73 |
|
chain stays (mm) |
410 |
410 |
410 |
410 |
410 |
410 |
|
bottom bracket drop (mm) |
70 |
70 |
66 |
66 |
66 |
66 |
|
fork length (mm) |
385 |
385 |
385 |
385 |
385 |
385 |
|
stand over height (mm) |
746 |
771 |
792 |
810 |
826 |
853 |
|
stack (mm) |
517 |
529 |
542 |
557 |
571 |
593 |
|
reach (mm) |
377 |
384 |
390 |
395 |
400 |
409 |
|
wheel base (mm) |
987 |
984 |
992 |
992 |
1002 |
1011 |
All measurements are in mm unless otherwise stated.
The above table shows the standard geometry for the bicycle as shipped, other geometry configurations may be available with certain bikes. Please contact us via Live Chat to find out more.
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Merida Reacto 4000 2027 - Road Bike
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