Merida Reacto 5000 review

The best Reacto yet

Our rating 
4.5 out of 5 star rating 4.5
GBP £2,000.00 RRP | AUD $2,999.00

Our review

The Reacto 5000 proves that aero doesn’t have to mean bone-shaking, and seriously expands its real-world usability because of it
Buy if, You want to reap some aerodynamic benefit on every ride for free
Pros: Great ride quality and handling, surprising comfort, Ultegra parts
Cons: Some lower spec parts to allow for the fine frameset
Skip to view product specifications

There’s nothing to stop every last watt of your energy reaching the back wheel on Merida’s new Reacto. Just look at those chainstays, they’re enormous.

  • The Merida Reacto 5000 is one of our Bike of the Year bikes for 2018. To read reviews of the other contenders and the categories tested across road, mountain and women’s bikes, visit our Bike of the Year hub.

At more than 50mm deep behind the bottom-bracket shell, very boxy and asymmetric, they look as muscular as a lion’s haunches, and with similarly powerful intent.

Merida’s original Reacto appeared in 2011, with the Reacto II arriving in 2014. The 2018 Reacto III is claimed to improve on the outgoing bike’s comfort, weight and aerodynamics, and if it didn’t I’d be surprised.

All the tubes are slimmer and the seatstays meet the seat tube lower down, their enhanced aerodynamics supposedly saving up to 5 percent of your energy at 45km/h.

The frameset’s weight has been reduced by around 17 percent thanks to the slimmer tubes and new carbon-fibre layup, but stiffness is unchanged.

Every tube except the top tube and chainstays has a NACA Fastback profile, or truncated wing shape, and the narrower head tube means the headset’s lower bearing reduces from 1.5in to 1.25in.

Preferring to keep things simple for servicing, all the cables enter a large port in the top of the down tube, behind the head tube, and the brakes are straightforward direct-mount items.

The Merida’s solidity and fine handling helps it carry good corner speed and enables instinctive line changes

Merida Reacto 5000 geometry

The CF2 geometry of the Reacto 5000 is less aggressive than the top-spec models, with a shorter reach and a 177mm head tube that’s 20mm taller than the equivalent-sized CF4 model. But I found my M/L (54cm) machine a great fit, and similar to the usual 56cm bikes.

With no spacers, the reach was ideal for adopting a good position, low on the drops or on the hoods with flat arms, I definitely didn’t feel cramped.

Contact points are important, and Merida’s Race saddle is surprisingly comfortable, with the right level of padding for support without feeling squashy. The Merida Aero alloy bar has mildly flattened tops, which make more sense as a comfortable hand rest rather than being especially aero.

The drops are ergonomic, and along with the stem, make for a stiff cockpit. What I really noticed though were Shimano’s new Ultegra levers, which just feel more refined than 105, with comfy hoods and lightning-fast gear shifts.

They’re paired with Ultegra mechs, but then Merida deviates with an FSA Gossamer Pro chainset and 105 direct mount brakes, plus 105 cassette.

From the saddle most of these are harder to notice, except for the brakes, which just lack the instant bite I expected, and the rear in particular has quite a wooden feel.

Below chainstay brakes have always come with compromises, one of which is the additional dirt they collect, and the extra faff involved in working on them.

The 105 direct-mount brake did stay centred and I didn’t detect any rubbing from the wheel, but its inline quick release is large and positioned prominently in front of the head tube, potentially affecting the carefully designed aerodynamics.

Merida Reacto 5000 ride experience

With superb lateral stiffness and power delivery, the Reacto 5000 is keen to get up the road. Merida’s alloy-rimmed Expert CW shallow aero wheelset, with 28 paired, opposing J-bend spokes each, tries hard and does a reasonable job of converting your inputs to speed, but it’s not the most reactive.

Carrying speed into uphill drags allows you to power over the top with little velocity loss, but starting steep climbs from slow speed shows their limited acceleration.

Even so, the Reacto 5000 is a good climber, with great composure and balance to go with its efficiency, and some sportier wheels would unlock even more potential.

The 52/36 and 11-28 gearing is ideal fast road gearing, and well suited to the Reacto’s ability. Continental’s 25mm Grand Sport Race tyres measure 26.5mm for a little extra volume, and handle predictably with decent grip, making descending a confident experience.

The Merida’s solidity and fine handling helps it carry good corner speed and enables instinctive line changes, feeling refined and comfortable, no matter what the road surface.

Although Merida says the Reacto is limited to 25mm tyres, there looks to be room for 28mm rubber, to further enhance the frame’s excellent vibration absorption.

The chunky-looking aero seatpost is Merida’s S-Flex design, with a large silicone rubber-filled window in its trailing edge that leaves the rough equivalent of a 27.2mm post in front, which can flex more with the springy rubber section to dampen shocks.

The further I rode on the Reacto 5000, the more impressed I became. Its plush ride quality is at odds with the frame’s angular, oversized appearance, and its all-round stability and intuitive handling really enhanced the experience.

Yes, the wheelset and chainset cut costs, as to a lesser extent do the brakes, but the frameset itself is very good, and rather than only seeing it as an aero bike, consider it simply as a great road bike with aero benefits.

Also consider…

Interested in what else is available at this price point? Have a look at the following list of tried, tested and reviewed bikes.


Product Specifications


Name Reacto 5000
Brand Merida

Available Sizes XXS XS S S/M M/L L XL
Seatpost Merida Reacto carbon Race
All measurements for frame size tested ML
Reach (cm) 39
Stack (cm) 57.5
Head Tube (cm) 17.7
Frame size tested M/L
Wheelbase (cm) 99.5
Top Tube (cm) 56
Seat Tube (cm) 54
Chainstays (cm) 40.8
Wheelset Merida Expert CW
Weight (kg) 8.37
Stem Merida Expert alloy
Shifters Shimano Ultegra
Seat Angle 73.5
Bottom Bracket Press Fit
Saddle Merida Race
Rear Tyre Continental Grand Sport Race 25mm
Rear Derailleur Shimano Ultegra
Headset Type Merida Reacto
Head Angle 73
Handlebar Merida Expert Aero alloy
Front Tyre Continental Grand Sport Race 25mm
Front Derailleur Shimano Ultegra
Frame Material Reacto CF2
Fork Pro Full carbon tapered
Cranks FSA Gossamer Pro, 52/36
Chain KMC X11-1
Cassette Shimano 105 11-28
Brakes Shimano 105 direct mount front
Bottom-bracket drop (cm) 6.6