Genesis Bikes are best known for working with steel but last year dipped their toes into the world of carbon fibre with the launch of the Zero – now there’s a second carbon machine which captures the zeitgeist among bike brands.

Introducing, the Genesis Datum. It’s a bike which highlights two trends in the road world: disc brakes and versatility. By that we mean bikes which are, in fact, designed to venture off-road, while retaining plenty of speed and agility on it. Some call them gravel bikes, other have gone for ‘adventure road’, but for Genesis the Datum is, in their words, a “large-tyred, ruffty-tuffty carbon road disc bike”.

We went to check out the Datum at Genesis’ 2016 launch and spied plenty of highlights from across the range, including the Croix de Fer Titanium, Equilibrium Disc and updated Zero, so read on for more on all of that, but first let’s delve into detail on the Datum.

Geometry

Genesis haven’t called the Datum a gravel bike because, in simple terms, it isn’t one. The geometry is based around the exceptionally popular Genesis Equilibrium and so has a distinct road bias, according to Genesis brand manager Albert Steward. While a typical gravel bike has a slacker headtube, longer wheelbase and sits somewhere towards a cyclo-cross and road bike, the Datum leans more towards the road in geometry terms.

“The 72 degree head angle and 50mm offset fork across the size run is a decidedly different approach to the 70-71 degree headtube of most other manufacturers’ gravel/adventure bikes,” says Steward. The result is a distinctly road biased 59mm trail to keep the feeling of agility without sacrificing stability, particularly at speed and also maintaining a healthy toe-clearance, particularly with the smaller frame sizes.”

The Datum will be available in five sizes from XS to XL and, taking a medium as an example, has a 561mm toptube, 73.25 headtube angle, 72 degree seattube angle and 155mm headtube. If that headtube sounds short then the fork had a CX axle-crown of 397mm which brings the front end. As a result, the medium frame has a stack of 585mm and a reach of 385mm.

“[The Datum will] comfortably sit mile-after-mile on tarmac, but, should the tarmac come to an end, it won’t mean turning back or the premature end of the ride,” adds Steward. “Not necessarily about out-and-out overall speed, but more fun, adventure, exploration and pneumatically-suspended comfort.”

Frame features

The Datum is made from a mix of 24 and 30-ton high-modulus carbon fibre with a BB86 PressFit bottom bracket and tapered headtube, features which give a clue as to the performance-focused DNA of the frame.

Practicality is at the heart of the frame, though, and it has mudguard eyelets (but no rack mounts) at the front and rear, and tons of clearance. While a seattube cutout is usually a feature on aero frames, it’s used on the Datum to match the rear tyre clearance to the front, without needing to unduly lengthen the chainstays. Steward says this helps the Datum retain the sharp handling of a road machine. As a result, the frame has 420mm chainstays, mirroring the Equilibrium, but can take a 33mm tyre with full mudguards fitted.

A by-product of seattube cutout that Genesis discovered during prototype testing is that it also improves the comfort of the frame, while they’ve used a skinny 27.2mm seatpost, as is pretty much standard now, in a bid to add a little more compliance to the ride.

Disc brakes

The Datum is a disc-equipped machine and Genesis have opted for a 15mm thru-axle fork to cope with the additional forces of disc brakes while also, Steward says, improving the stiffness of the front-end. The rear dropouts take a typical road quick release skewer, however, as it’s more affordable, the frame doesn’t require the additional stiffness at the rear, and wheel ejection is only a potential problem at the front.

The frame uses the newly-introduced flat mount disc standard – there looks be some agreement between manufacturers now that flat mount is the best solution for road disc bikes – and the rear has been designed to accommodate a TRP Hy/Rd cable-actuated hydraulic caliper on an 160mm flat mount adapator, with Genesis thinking that if that combination will fit, then anything will.

Specs

The Datum will be available as a frameset (both Di2 and mechanical compatible) for £999.999, as well in three builds.

The entry-level model, the Datum 10, is the machine pictured here and has a striking ‘post box red’ paintjob. The frame is dressed in a Shimano Tiagra groupset, TRP Hy/Rd disc brakes, Fulcrum Racing Sport DB CX wheels and new 33mm Challenge Strada Biancha tyres for £1,799.99.

Step up a level and you’ll find the £2,099.99 Datum 20 (with a ‘raw carbon gloss black’ frame’), which gets an upgraded Shimano 105 groupset and Shimano BR-RS505 hydraulic disc brakes, and the same wheels and tyres as the Datum 10.

At the top of the range is the Datum 30 (with an ‘oyster’ finish) for £3,199.99. You get a Shimano Ultegra Di2 groupset and Shimano BR-RS805 hydraulic disc brakes for your money, and then, once again, the same wheels and tyres as the other two bikes.

All three machines comes with a compact 50-34t chainset paired with a wide-ranging 11-32t cassette, providing a huge spread of gears for climbing. Genesis have also specced their own-brand RandoX Flared handlebar, which has a compact shape (the drop is 125mm and the reach is 70mm), backswept tops (six degrees from the centre) and flared drops (eight degrees).

The Datum will be available from October and if that’s whet your appetite then check out the gallery below. But we’re not done with Genesis yet – flick on to the next page for more from the British brand’s 2016 range, starting with the Croix de Fer Titanium…