B'Twin Mach 720

With a punchy ride and fast turn of pace, the B'Twin Mach 720 from French sports superstore Decathlon is every bit as good on the road as its £1,000 specification suggests it is on paper. There are few bikes that offer such good value for money and enjoyable performance.

Ride

The Mach's carbon fibre frameset, with its angular lines and sharp creases, delivers a stiff and responsive ride. The frame has clearly been built to be stiff, but B'Twin have sought to balance this stiffness with a dose of ride comfort. The lower half of the frame (down tube, bottom bracket, chainstays) and fork have been built to provide a high level of stiffness, so there are some big profile tubes and plenty of reinforcing material. The top half of the frame is altogether more slender in profile, with skinny kinked seatstays and a tapered top tube that manage to impart a decent amount of comfort into the ride.

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Does it work? Yes, is the simple answer. The Mach 720 is stiff when you're applying maximum power, with a crisp reaction to your pedalling. Move the bike around on the road and through bends and it feels direct and responsive. The steering provides a good amount of detail, and there's enough feedback through the carbon fork about the road surface to let you push on in earnest without much risk of overcooking it into the corners. Settle down to a steady cruising speed and the Mach 720 impressively soaks up all the vibrations caused by riding over crumpled tarmac and scarred road surfaces.

The Mach 720 is all about going fast. It's very much a race machine, developed with input from B'Twin's under-19 racing team. That explains the short head tube, which promotes a low and aerodynamic position – great if you like getting your head down and pushing on as fast as possible. The top tube is also long, 55cm on this 53cm model, which gives a good stretch to the bar. This would make a great race bike or fast sportive bike, if you ride with an emphasis on fast times rather than a social pace.

Only the slightly high weight of 8.8kg (19.4lb) is a blemish on an otherwise top marks bike. On the flat and over rolling roads it's less of a problem, but you can feel it on the steeper climbs, though fortunately the 11-28 cassette provides some nice low bailout gears for winching your way up.

Frameset

It has to be said, it's an unusual looking frame. The sharp lines and angles are not to everyone's taste, but I will add that it's a grower; I've come to really like its distinctive looks in the time I've spent with it. The subtle paint job and understated decals work well. And the appearance does mean it fools many people into thinking it's a more expensive bike than it actually is.

The frame is packed with modern details. There's a tapered head tube and fully internal cable routing. One detail isn't very modern though: the external threaded bottom bracket. Most top-end carbon frames have moved to press-fit bottom brackets but a lot of people aren't fans, and the external type is certainly easier to service and less prone to the creaking of a press-fit assembly.

The half-height seatmast is an unusual design. The last bike I can remember seeing it on was the old Trek Madone. B'Twin's reasoning behind it is that the elevated seat clamp frees up the top tube/seat tube/seatstay junction to provide a greater degree of deflection for comfort. Whether it works or not is tricky to say, but there's no doubting the smooth ride the bike offers.

B'Twin claim a 1,150g frame weight; add in a 320g carbon fork and that's a decent weight for any carbon frameset, let alone one costing £1,000 overall. That makes the frameset a good investment: upgrade a few components along the way, some lighter wheels and even a higher spec chainset and cassette when these bits wear out, and you could easily drop a decent chunk of weight from it.

Build

A grand is really the tipping point where we see carbon fibre becoming an alternative to aluminium, the frame material dominant on bikes costing under £1,000. That said, your choices are still very limited, as our 15 of The Best Road Bikes Under £1,000 buyer's guide shows. An aluminium bike still looks to offer the best value at this price, but it's impressive that B'Twin manage to offer such a well-equipped carbon bike for the money.

Even more impressive is that it comes with a predominantly Shimano 105 11-speed groupset. You have to look at carbon road bikes costing several hundreds more to find a similar specification. It's not quite a clean sweep of 105 parts – there's a Shimano non-series 52/36 semi-compact chainset and B'Twin branded brake callipers – but it all works brilliantly, as you'd expect from Shimano, with clean shifting across the 11-28 cassette from the very ergonomic shifters. That cassette combines smartly with the 52/36 chainset (which we're big fans of here at road.cc) to provide a generous range of gears, low enough to crawl up steep hills and high enough to maintain race speeds. The brakes have good lever feel with plenty of power to easily scrub off excess speed when hurtling down the hills.

The B'Twin own-brand wheels have an aero shaped 24mm-deep aluminium rim, and a claimed 1,760g weight which is pretty good. The wheels feel zippy and stiff when loading up through corners, and the braking surface delivered good results in the dry and wet. The 23mm Hutchinson Equinox tyres provide good grip in the dry and wet and roll well, but at 290g each they're a bit on the heavy side for a race tyre.

The B'Twin-branded aluminium shallow-drop handlebar is a comfortable shape and the stem provides a smart appearance. A generous number of spacers on the steerer tube allows a degree of height adjustment. The inclusion of bolt-in bar end plugs is a really nice touch and ensures the plugs can't accidentally fall out. I'd happily see them fitted to all bikes as standard.

I really didn't get on with the saddle, it's simply the wrong shape for me, so I swapped it out for a favourite for the rest of the test. The seatpost features a two-bolt head so it's easy to get the saddle in the exact position you need it. The Mach 720 even comes with a set of pedals so it really is ready to ride straight from the box or shop.

Conclusion

With its fast ride and smart handling, a mostly Shimano 105 11-speed drivetrain and decent parts package, the B'Twin Mach 720 is an absolutely cracking bike for the money. It easily outclasses other bikes at this price. If you're looking for a fast performance road bike for a grand there aren't as many compelling choices as this B'Twin.

Verdict

Fast and comfortable ride, and cracking Shimano 105 11-speed kit