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Just in: Merida Reacto 5000

A carbon-fibre aero road bike with Shimano Ultegra components for £2,000

The Merida Reacto 5000 aero road bike has just arrived for testing here at Boasting a carbon-fibre frame, a mainly Shimano Ultegra groupset and Fulcrum Racing Quattro wheels, it costs £2,000.

We’re all familiar with aero road bikes these days, right? The reasoning goes that saving weight on a frameset is an overrated factor that’s only really significant when you’re accelerating or climbing a very steep hill. At other times, aerodynamic efficiency is much more important.

With that in mind, the Reacto 5000 is built using Merida’s Fastback tube profiles which are based on the NACA (National Advisory Committee for Aeronautics) 0028 airfoil.

Merida Reacto 5000 - seat tube junction.jpg

The tail of the profile is cut away in such a way as to keep the airflow stable without causing turbulence. This lowers the weight and allows Merida to stay within the UCI’s rules on tube dimensions. Other brands do similar things with their aerodynamic shaping. 

The seatstays meet the seat tube much lower than the top tube junction, reducing the frontal area, and they're positioned well out from the rear wheel to manage airflow back there.

Merida Reacto 5000 - frame detail.jpg

The legs of Merida’s full-carbon Pro-Direct fork are widely spaced too, and the crown is integrated into the frame. In other words, it sits in a notch at the bottom of the head tube so as not to increase the size of the bike’s silhouette.

Merida Reacto 5000 - fork.jpg

The front brake is direct mount, positioned at the front of the fork rather than behind it. Merida says that the aero advantage to be gained by sheltering the brake around the back of the fork legs is minimal.

Merida Reacto 5000 - bottom bracket.jpg

The rear brake is direct mount too, hidden away on the underside of the chainstays. This allows Merida to do away with a brake bridge between the seatstays, keeping things clean in that area for more aero efficiency. The downside is that brakes positioned down there invariably get dirty in wet conditions because they’re right in the firing line of spray from the road.

Merida Reacto 5000 - brake release.jpg

The seat tube is cutaway around the leading edge of the rear wheel in a time trial bike style and the carbon-fibre seatpost that slots in at the top mimics its aero profile. Interestingly, that seatpost features what Merida calls its S-Flex technology. The post thins out just below the head, the gap filled with a soft rubber insert. The idea is that this adds flexibility over rough surfaces to reduce ‘muscular exhaustion’. Merida reckons it acts like a standard 27.2mm diameter post. 

Merida Reacto 5000 - seat post flex.jpg

The post’s other clever feature is the flip-flop head – you can spin it to effectively alter your seat angle. You’re probably not going to want to make use of that for normal road use, but it might come in handy if you fit clip-on aero bars for a time trial or triathlon.

The seat clamp is integrated – it’s a wedge design – and the cables run internally, tunnelling into the frame via the top tube.

Merida Reacto 5000 - saddle.jpg

Although this is a race bike, the geometry isn’t extreme. We have the 56cm model for review which comes with a 575mm top tube and a 184mm head tube. The stack (the vertical distance between the centre of the bottom bracket and the top of the head tube) is 578mm and the reach (the horizontal distance between those two points) is 398mm. That’s certainly a setup designed for efficiency, but the front end isn’t radically low. 

Merida Reacto 5000 - rear dropout.jpg

The Reacto is available in several different models. The lower end ones are aluminium, kicking off with the Reacto 300 that we reviewed here on last year It was priced £999.99 at the time although the price has now dropped by £100. We were very impressed with the performance so this bike is looking even more of a bargain now.

Merida Reacto 5000 - shifter.jpg

The Reacto 400 now fills the £999.99 slot, equipped with Shimano 105 shifters and derailleurs, while the £1,250 Reacto 500 has a Shimano Ultegra-based spec.

Merida Reacto 5000 - bar tape.jpg

From there on up the Reactos are carbon-fibre, starting with the £1,700 Reacto 4000 which features 105 shifters and derailleurs and going right up to the £7,000 Reacto Team. This one has a superlight version of the frame, Shimano Dura-Ace Di2 (electronic) shifters and derailleurs, Fulcrum Quattro 35 carbon wheels and a Rotor Flow noQ chainset. As the name suggests, this build is based on that of the Lampre-Merida professional squad.

Merida Reacto 5000 - rear mech.jpg

The Reacto 5000 comes fitted with Shimano Ultegra shifters and derailleurs and an FSA Gossamer Pro chainset. It’s a semi-compact (or ‘faux pro’, or whatever else we’re calling it these days) model with 52/39-tooth chainrings teamed up with an 11-28-tooth cassette. 

Merida Reacto 5000 - front mech.jpg

Read our Shimano Ultegra 6800 groupset review here.

The direct mount brakes I mentioned are Shimano 105 while the wheels are Fulcrum Racing Quattros fitted with Continental Grand Sport Race tyres in a 25mm width.

Merida Reacto 5000 - rim and tyre.jpg

The Reacto 5000 isn’t especially light at 8.37kg (18.5lb) but, as mentioned up top, that’s really not the point of this bike. If you want light weight, check out Merida’s Scultura lineup. We’ve just reviewed the £2,300 Scultura 6000 which has a stunning frameset for the price.

The Reacto 5000 has many rivals at the £2,000 price point. The Specialized Tarmac Comp that we reviewed last year (Merida owns a big stake in Specialized, by the way) was £2,000 as well, and it remains that price for 2016. 

Merida Reacto 5000 head tube

That bike has a mostly Shimano Ultegra build and it offers a sparkling ride, although it’s not designed with aerodynamics in mind. 

The £2,299 Look 765 that we reviewed recently also impressed us. That bike is also built up with Shimano Ultegra although it’s an endurance model rather than a race machine.

I’m going to get the Reacto 5000 set up and out on the road, and will be back with a review soon. In the meantime, get more info from


Mat has been in cycling media since 1996, on titles including BikeRadar, Total Bike, Total Mountain Bike, What Mountain Bike and Mountain Biking UK, and he has been editor of 220 Triathlon and Cycling Plus. Mat has been technical editor for over a decade, testing bikes, fettling the latest kit, and trying out the most up-to-the-minute clothing. We send him off around the world to get all the news from launches and shows too. He has won his category in Ironman UK 70.3 and finished on the podium in both marathons he has run. Mat is a Cambridge graduate who did a post-grad in magazine journalism, and he is a winner of the Cycling Media Award for Specialist Online Writer. Now over 50, he's riding road and gravel bikes most days for fun and fitness rather than training for competitions.

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fukawitribe | 8 years ago



It’s a semi-compact (or ‘faux pro’, or whatever else we’re calling it these days) model with 52/39-tooth chainrings

Wee typo - should be 52/36.

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