Just in: Rose X-LITE CW-4100 Di2 aero disc bike

The Rose X-Lite CW is an aerodynamic road bike and was introduced by the German bike brand in 2015. It's available in two versions - one with disc brakes or one with direct mount caliper brakes, we've got the former in for test. Before it hits the road, here's an overview of the key details. 

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Our model is wearing a full Shimano Dura-Ace Di2 groupset with hydraulic disc brakes. It's a build that will set you back £4,611.83, which is very competitive for a Dura-Ace specced bike. That price also includes DT Swiss Spline C38C db wheels, a carbon fibre clincher rim with a claimed 1,445g weight. The rims have an 18mm inner width and are tubeless-ready, and the hubs use Shimano’s Center Lock for mounting the disc rotors. They do come with a maximum rider weight limit of 110kg, though. You've been warned. 

Our bike is sporting the distinctive Profile Designs Canta Ergo handlebar. It’s shaped to offer optimum comfort, with an ergonomic and contoured top section for cruising comfort, and shallow and short reach drops so you can easily get into the aero tuck. Cables are routed inside the handlebar to maintain the smooth lines and bar tape. It’s clamped to the frame via a sleek Aeria Stem. As its looks suggest, it is designed to reduce drag with a smooth faceplate that hides the bolts from the airflow. 

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A pair of Continental Grand Prix 4000S II tyres in a 25mm width - tyre clearance is pretty generous for a racy aero road bike, and 28mm tyres are accommodated in the frame and fork. The rim brake version only takes up to 25mm, so that extra tyre clearance is a clear benefit of going with disc brakes. A Fizik Aliante saddle completes the build details.

The frame has clearly been designed to slip through the air cleanly, with truncated aero main tubes, a seat tube that hugs the rear wheel, an integrated 2-bolt seat clamp and an aero seatpost. Rose claims 8% less drag with this new and improved bike. Will the aerodynamic benefits of the new bike be enough to offset the apparent drag caused by disc brakes? We don’t know, and Rose doesn’t offer any aero data like Specialized did at the launch of the new Venge ViAS Disc. Frame weight is 990g which is good for an aero road frame.

It's a smart looking bike and uses all the modern details that we are coming to expect on the latest disc-equipped road bikes. We're talking things like flat mount disc caliper mounts, 12mm thru-axles at both ends and full internal cable routing. 

There’s full internal routing for the electronic wires for the groupset and the hydraulic hoses are also hidden inside the frame and fork. It’s all very neat and tidy. There are three bottle bosses on the down tube, the standard position or a lower position which is claimed to be more aerodynamic. To appeal to multisport types, the seatpost can be flipped around to steepen the effective seat angle and push the saddle further forward.

Aero and disc bikes usually come in a fair bit heavier than their regular counterparts, but at 7.46kg (16.44lb) for the size 57cm pictured, it’s narrowing the gap. 

Buying a Rose is a bit different in that you can fully customise the spec of the bike, so if there are components on this bike you don't like, or you want to substitute the Dura-Ace Di2 for a more affordable groupset, you can change any part of it until you hit a satisfactory price or build. More info at www.rosebikes.com