Trek Domane SL5 Disc review

The Domane, so says Trek, has it all: ‘Blistering speed, incredible race comfort and stability, even on the punishing pavé of Flanders and Roubaix.’

So, is this the bike you’d want underneath you in order to undertake those sportives that follow the routes of the cobbled Classics? Wearing voluminous 32c rubber, and featuring vibration-damping technology, there could be some mileage in that...

Frameset

The headline feature of the Domane’s frameset is its IsoSpeed decoupling system. At the rear of the bike, a rocker at the junction of the seat tube and the top tube enables the two frame tubes to de-couple, allowing the seat tube to flex in response to changing road surfaces.

A similar system is employed at the front end, which allows the steerer to flex, taking the sting out of bumps. Crucially, it doesn’t flex laterally, so in theory does nothing to the detriment of steering accuracy.

The frame itself is constructed from Trek’s Optimum Compaction Low Void (OCLV) carbon, which aims to achieve a balance of lightweight, strength and stiffness.

The Domane features Trek’s ‘endurance fit’ geometry, with a higher head tube than the firm’s racing models for better stability. A measured head angle of 71.3° places it firmly in the ‘endurance geometry’ camp.

Thru-axles are employed front and rear, to reduce flex under power at the forks and rear stays. There’s also ample clearance for the 32c tyres this bike runs.

Whether you’d want to fit wider rubber or not, there’s space for cyclocross tyres between the fork and seatstays.

Groupset

The SL5 is fitted with a Shimano 105 groupset. It may be mid-level componentry but everything works well. Sometimes it’s better to have a unified approach to a groupset, rather than throw in a higher-spec chainset at the expense of a lower-end cassette, for instance.

The Domane has a compact, 50/34 chainset, and 105 mechs at the front and rear. Shimano’s RS505 shifters (equivalent to 105 standard) operate the derailleurs, while the brake levers operate the hydraulic discs.

An 11-32 cassette offers a wide choice of gears, while even the chain comes from Shimano’s dependable groupset.

Finishing kit

Trek’s in-house brand Bontrager supplies the finishing kit, with acceptable alloy kit at the cockpit comprised of a 100mm stem and compact drop handlebars with a comfortable 400mm diameter, and even more comfy Isozone foam padding.

Narrower bars allow rapid response and ample leverage up front. The two-part seatpost is Bontrager’s ‘ride-tuned’ off ering, with an oversized carbon seatcap sheathing the extended seat tube.

It’s worth trying your chosen size model in a bike shop, as the seatmast has a maximum extension limit that may not be right for you even on the correct frame size.

On top of this you’ll find an Affinity Comp saddle which is also built for comfort.

Wheels

Unusually for Trek, Bontrager wheels have been eschewed on the Domane, in favour of deep-section Vision Metrons.

Their 40mm section caused us no difficulty in crosswinds. Bontrager R2 rubber around their circumference also add to the comfort levels, but not at the expense of too much performance.

Even running low pressures, steering and grip are confidence-inspiring enough to push through even the roughest corners.

On the road

Everything just fits on the Domane. It’s not too often we find a good, comfortable riding position right away, but the Trek offers a fairly upright stance that also feels like it’ll respond to big power.

The steep seatpost noticeably puts us right over the front end, while Shimano’s hydro brake hoods offer a happy place for our hands to rest.

A number of things hit home within the first 10 miles of our ride. Firstly, the 32c tyres of the Domane are a clear game-changer – it’s eye-opening to spend so long on tyres so fat; normally we’d reserve rubber this wide for smashing up and down bridleways.

Their high-volume, low-pressure set-up takes any bite out of the road, leaving us feeling refreshed enough to not bother with a cafe stop.

Secondly, although it seems like a trifling detail, the fitment of foam pads directly to the Domane’s handlebar tops (before they’ve been wrapped in tape) means you can ride with your palms on the bar tops for miles with none of the vibration that often travels up your wrists in this position.

Beyond these two observations, the stand-out impression is that this a bike that’s easily the most stable of the four we’re testing.

Its wheelbase is the only one to push beyond the one-metre mark, and a very easy-going head angle and high head tube allow the miles to be despatched in comfort and confidence.

However, this is slightly at the expense of excitement. Hills also present an issue. Yes, there’s a 34x32 gear at hand if you’re struggling, but a package weighing 8.60kg doesn’t put you on the front foot to begin with. That said, Paris-Roubaix isn’t the hilliest race in the world...

Built for distance

The over-riding impression is of a bike that prevents fatigue admirably and is built for distance.

In terms of handling, what we’re also searching for is a bike that will handle with the best, especially in a group of sportive riders of potentially differing levels of bike handling ability.

Once you gel with the slightly more ponderous cornering performance of the Domane, it all clicks, but you need to get your braking done in advance for downhill corners.

Which isn’t to say you can’t haul the SL5 up in short order – its hydraulic stoppers are powerful enough to almost halt the bike with two-finger braking, while smaller, finer inputs of braking are easily applied.

It’s gratifying to notice that the IsoSpeed decoupler at the front end has no effect on steering accuracy. It does its vibration-eliminating job well on pitted lanes, but its operation is hard to notice in corners.

Again, we’re looking at a solid, predictable steerer here. With 1.5 inches (pesky Imperial-system-loving Americans) of stem spacers to play with, it’s very easy to get lower over the front for a more aggressive riding position.

A seat angle of almost 75 degrees tips you forward onto the bars naturally, so all the ingredients are there for a happy sportive experience, getting you to each feed stop with a much less numb bum than most of those around you.

It’s a toss-up, but if you value comfort over all else, buy a Domane this minute. If you’re eyeing hilly courses and love the taste of adrenaline in your mouth, try something different.

Ratings

Frame: Its unique build provides flex and comfort in spades. 9/10
Components: Mid-level Shimano 105 throughout. Good, though. 7/10 
Wheels: Deep-section hoops add to the high comfort levels. 8/10 
The Ride: Super easy on your body without ever being boring. 8/10

VERDICT

Trek's fat-tyred cobble-tamer has all the ingredients you need for a happy sportive experience.

Geometry

Spec