Reacto 4000 2026

The Reacto has always been a class leading aero road bike, combining state of the art aerodynamics with rider comfort. The latest generation incorporated wider tyres for increased comfort, but adding wider tyres resulted in aerodynamic compromises so a myriad of small improvements were required to over-compensate. 

In the World Tour no area can be ignored. Computational Fluid Dynamics (CFD) was used to model virtual wind tunnel performance, guiding the changes which offered the most aerodynamic benefit: Tiny details like integrating the front Disc Cooler behind the fork and the rear disc caliper in the rear triangle and creating new bolt through axles with the thread integrated into the fork dropout minimise drag and improve aerodynamic performance.

The Reacto CF5 needs just 209 watts effort for 45 km/h speed, All Reacto have powerful hydraulic disc brakes with chainstay mounted calipers for better brake force dissipation. The flat mount standard keeps everything neat whilst sitting calipers on CNC'd aluminium Disc Cooler fins helps reduce operating temperatures by up to 35%.

Cycling Weekly: 'without doubt one of the most complete bikes available on the market', Cycling news 'an utterly brilliant and faultless machine' and Cycling Plus were 'hugely impressed'.

Specifications::Reacto 4000

• Discipline: TT/Aer-Road

• Material: Carbon

• Front Travel: Rigid

• Rear Travel: N/A

• Wheel Size: 700c

• Warranty: Lifetime

Frame - CF3 IV - carbon with the same geometry and aerodynamic 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
Handlebar - Merida Expert CW; material: aluminium; (XXXS-S) - 380mm wide, (M-L) - 400mm wide, XL - 420mm wide
Grip - Merida Road Expert
Brake Type - Hydraulic Disc
Brake Lever - Shimano 105
Front Brake - Shimano 105; Hydraulic disc with Shimano RT54; 160mm
Rear Brake - Shimano 105; Hydraulic disc with Shimano RT54; 160mm
Front Tyre - Continental Grand Prix; 700x28C; kevlar bead
Rear Tyre - Continental Grand Prix; 700x28C; kevlar bead
Wheel Size - 700c
Rim - Merida Expert CW; 19mm inner rim width; 30mm rim depth
Spokes - Double Butted Black stainless
Front Hub - Shimano HB-TC500; 100x12mm; 28 Spoke; Centerlock
Rear Hub - Shimano FH-TC500-HL; 12-142mm; 28 Spoke; Centerlock
Speeds - 24
Front Derailleur - Shimano 105
Rear Derailleur - Shimano 105; GS
Shift Levers - Front: Shimano 105 disc, Rear: Shimano 105 disc
Chain - Shimano M6100-12
Cassette - Shimano 105 R7101; 11-34 teeth; 12 speed
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
Pedals - Not included
Saddle - Merida Expert SL; 6% recycled and 23% nature material; V-mount; incl. Merida minitool
Seat Post - Merida Team CW; Aero shape; 15mm layback; material: carbon