Specialized Roubaix SL4 Disc review

The latest Roubaix SL4 is by far and away the best yet. The frame is a little more aggressive than previous versions and its Zertz seatstays and forks seem to be actively suppressing the sort of surface vibrations that cause fatigue and numbness in your palms on bikes that offer less cushioning.

• Highs: Smoothness, stability and great handling
• Lows: Mediocre kit and it’s heavy for the money
• Buy if: You want a quality chassis and are prepared to upgrade

Specialized has integrated the disc brakes well into the carbon chassis. It hasn’t just bolted on – or bonded on – mounts and removed the caliper mounts. It has also reworked the internal routing, which allows it to slide hydraulic lines through the frame – though this entry-level model comes with cable discs. The front brake line is clipped to the fork’s leading edge, the Zertz inserts making it hard to run an internal line.

A large chunk of this bike’s price has gone into the classy frameset. The result is much more modest kit than seen on most bikes at this price point. The drivetrain is nine-speed Shimano Sora, the wheels quite basic Axis 2.0s. And we can’t help but think that this will be a hard sell up against plenty of 105-equipped bikes (and a few with Ultegra) at a similar price.

Handling on rutted roads is superb, but start ascending and the SL4’s weight starts to drag

It’s not all bad news, though. On the road the Roubaix’s class shines through, its ride balancing smoothness, stiffness and responsiveness. On gravel military roads and deeply rutted lanes the Roubaix pushes through where a road bike has no place being – never mind being so good when it’s there.

We passed signs indicating that tanks use these lanes – leaving them in quite a state. But the Espoir tyres have plenty of traction. Their stated size is 25mm but these are actually closer to 28mm wide and soft, gummy and tough.

Avid’s BB7s are the classic cable disc brakes. Compared with Shimano, they feel harder at the lever but with more powerful stopping ability. The reduced travel takes a little getting used to, but we certainly appreciated the performance, especially on broken surfaces and in the wet.

Avid supplies its BB7 cable disc brakes

One downside of the SL4 and its lower level spec is its relatively portly weight, which makes climbing ponderous on longer drags. The compact chainset and 11-32 cassette meant we could manage all our test route’s ascents, but the Roubaix is never what you’d call a sprightly climber.

Our only other issue with the Roubaix relates to a small component – one we’ve mentioned before. Specialized continues to spec a 30mm cone-shaped top to the headset bearing, which limits height adjustment. We kept wanting to lower the bar but even with the Comp-Set adjustable stem we couldn’t lower the front as much as we’d have liked.

You’re paying a lot for the SL4. For that you do get a great frame and a good ride – but its spec tempers our excitement.