Trek Domane – A new bike for the cobbled Classics

Pivot allows seat tube to flex, boosting comfort

Trek’s new Domane, launched today in Kortrijk, Belgium, fills a long-standing and gaping hole in the company’s road bike line-up. It’s a proper Classics-type machine, with dedicated features to soften the blow of rough roads and relaxed geometry to better suit less-than-ideal conditions. It’s not just another cookie cutter version of that type of bike, though, but a completely original design with a novel – and remarkably effective – way of isolating the rider from the road.

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The key feature of the Domane (doh-MAH-nee, according to Trek) is a new seat-tube-based suspension system called IsoSpeed. While most ‘endurance’ road bikes are designed to provide comfort-boosting flex via tuned tube shapes and carbon fiber layups, IsoSpeed is a mechanical system that partially decouples the top tube from the seat tube by incorporating a cartridge bearing pivot at the seat cluster.

The seat cluster is no longer a rigidly fixed joint but rather more like an ‘X’, with the two straight lines now able to rotate about each other. What this does is allow the seat tube to flex fore-aft (and effectively, up and down slightly, too) without affecting the other frame tubes or compromising frame stiffness in other directions. In fact, Trek claim the Domane is actually stiffer than the Madone in both head tube and full frame rigidity, with gains of nine percent and six percent, respectively.

Claimed comfort gains are far more dramatic. According to Trek road product manager Ben Coates, internal testing shows a current Madone to flex vertically by about 23mm while the IsoSpeed-equipped Domane moves almost 36mm under the same load – an improvement of nearly 50 percent. Coates says IsoSpeed not only doesn’t make any major sacrifices but actually eliminates some problems that can come with a bike with lots of vertical flex built into the structure, especially when subjected to something as brutal as hitting Paris-Roubaix cobbles at full speed.

“Say you hit a bump on your bike – and on cobbles you actually hit them [with both wheels] at the same time – you have this counteractive scenario happening where your rear wheel wants to splay the bike and the front actually wants to compact the bike,” he explained. “When you put your weight on the saddle, it causes the compaction to be exacerbated because of the flex that comes through the top tube, and when it unloads – there’s no damping in a carbon frame, there’s no dissipation of energy – it just snaps back. This causes an over-center on the back end and the cycle just continues. So when your weight is more controlled over the system, it takes that element out away from that compaction/splay interaction.”

IsoSpeed is a pivot placed at the seat cluster. By partially decoupling the seat tube from the top tube, Trek claim the Domane offers far greater comfort than the Madone without affecting other frame performance metrics.
James Huang/BikeRadar

Coates contends that IsoSpeed is a nearly maintenance-free system, too. Mountain bikers will quickly recognize the assembly as a standard rear suspension pivot setup with two cartridge bearings and an aluminum pivot axle – all sealed with rubber and an additional protective carbon cover. “It’s a sealed system that’s designed to last basically for the duration of the bike,” he told BikeRadar. “The bearing quality and size is similar to what’s in a suspension bike, so the maintenance to replace them, if you have to, is less than five minutes.”

Coupled with IsoSpeed at the rear end is a new IsoSpeed fork and matching IsoZone carbon handlebar. Neither is a mechanical system, though. The fork features an extreme blade rake – a new-school take on an old-school approach to ride comfort. Actual rake would be prohibitively excessive with conventional straight dropouts, however, so Trek have offset it with rear-facing dropouts to yield a more typical dimension. Still, though, the Domane fork rake will measure a bigger than typical 48mm or 53mm depending on frame size.

As with the IsoSpeed rear end, Trek again claim measurable gains in comfort and side-to-side stiffness for the fork, with seven percent and 30 percent boosts, respectively – much subtler improvements but improvements nonetheless. The IsoZone handlebar is even more straightforward, incorporating gel pads into the tops (and the drops, depending on model) that Trek claim to measurably reduce hand vibration. Those pads are recessed into the bar, too, so outer diameter isn’t affected.

The Domane incorporates all of the geometry tricks Trek have learned on the cobbles over the years. The handling is slightly more relaxed than a standard road bike, the wheelbase is longer, the bottom bracket is 2mm lower and there’s more tire clearance front and rear – up to 25mm officially but by visual inspection, 28mm tires will easily clear. Trek also adapt the hidden fender mount system from the old Gary Fisher Cronus cyclo-cross bikes for even more versatility. Fit-wise, Coates says the Domane will be “different” from a Madone but the sizing scheme will carry over. Just one head tube length per size will be offered and hand position will be higher than on a Madone – somewhere in between the ‘H2’ and ‘H3’ fits according to Trek’s sizing scheme.

The Domane fork blades are radically splayed forward to help smooth the ride out front. Combined with the slack head angle, the result is a longer front center for stability but steering that’s still appropriately quick.
James Huang/BikeRadar

Despite all of this built-in comfort, the Domane is still surprisingly light with a claimed frame weight of 1,050g for a 56cm size and the IsoSpeed assembly itself supposedly adding only 50g. While the system offers a lot of movement, there really aren’t very many parts involved and the bearing seat for the rear IsoSpeed system is net molded right into the carbon structure, just like Trek have long done with headset and bottom bracket bearings.

Other features include a new 3S integrated and adjustable chain keeper bolted directly to the base of the seat tube, Trek’s integrated DuoTrap wireless speed and cadence sensor pocket in the non-driveside chainstay, refined internal cable routing for use with mechanical or electronic transmissions, and of course, the continuation of Trek’s ultra-wide BB90 bottom bracket and e2 tapered head tube concepts.

Why even bother with such a niche machine, though? Why should most riders care about a bike designed for conditions they’ll likely never see? While the Ronde van Vlaanderen is generally raced on standard – or only very slightly modified – road bikes, Paris-Roubaix’s notorious cobbles are an entirely different animal. They’re far bumpier, more slippery, and the gaps between the stones are bigger and more uneven. In short, it’s a veritable minefield – in essence, a longer and more intense version of what many amateurs contend with on a daily basis, particularly in the US Midwest.

More to the point, this is what many riders want – isolation from the road without sacrificing essential metrics like front triangle torsional stiffness, drivetrain efficiency, weight and aesthetics. “[Domane is] a bike built for epic riding,” said Coates. “It’s a bike built for long days, it’s comfortable and it’s racy. It’s got technology built into it that basically isolates your comfort from your power. It’s about staying comfortable and staying powerful. This is geometry based, technology based – everything is designed to increase efficiency.”

Complete bikes will start at around US$4,500 with Shimano Ultegra while Dura-Ace mechanical bikes will fetch around US$8,800. The Domane will be available through Trek’s Project One custom program, too, and it’ll also be offered as a bare frameset. Best of all, Trek say it’s available starting right now.

Going along with the new Trek Domane frame is the new Bontrager IsoZone carbon handlebar with integrated pads on the tops as well as the drops depending on model.
James Huang/BikeRadar

How the team played into the bike’s development

Trek have long built special machines for their sponsored teams tackling the brutal Northern Classics – from the rear-suspended SPA machines of the US Postal Service days to the just slightly tweaked geometry of last year’s Paris-Roubaix Madones. “That product fulfilled a specific racing need and was adapted to fulfill a specific market need,” said Coates. “We went away from that product a number of years ago, and our athletes for the cobbles races pretty much told us that they want to ride a rigid bike, just with a longer wheelbase and a little bit more tire clearance – they want to ride a full-on race bike.”

“It’s been a lot of years since our teams actually drove development,” he continued. “When we first started with US Postal, Johan, Julian, Lance, those guys knew a lot about wheels, they had a lot. They knew what they liked – wheels, handlebars, stems – and when we took over the Mavic and Deda sponsorships, they had a lot of history and our history was relatively short. And so they were helping us, they were telling us to look at these products, they were telling us about performance benefits that they needed.”

Team-driven development again came to the fore with the signing of Swiss powerhouse Fabian Cancellara, who’s not only one of the most successful Classics riders of the modern era but also someone who’s renowned for being fanatical about his equipment. “We signed up Fabian Cancellara, and he’s a technician,” said Coates. “He cares about his bike; he’s looking for an advantage. He’s specific about what he wants, and last year we went into a bunch of testing with him and we learned a lot of things.

“We did strain gauge testing; we did accelerometer testing on the cobbles with athletes to get a real idea what’s happening in those scenarios. We did a test session with Fabien and [the late] Wouter Weylandt. They weren’t rigged up with all the testing stuff but we ran Trek people through with all the stuff at that point. We did blind bicycle analysis. We did a bunch of questionnaires and blind testing, mix and match, and filled out all the surveys and we came away with this immense amount of knowledge of what actually happens in a bicycle.”

Cancellara (Radioshack-Nissan-Trek) has already put that knowledge to good use, scoring the first win on a Domane at Strade Bianche in early March. The big Swiss rider is one of the heavy favorites for Ronde van Vlaanderen and Paris-Roubaix, too, and not surprisingly, he plans to use his new Domane there as well. What is surprising, though, is that Cancellara supposedly wants to ride the Domane all season – including for this year’s Tour de France. The Madone may still be Trek’s premier Grand Tour bike but if all of these claims hold true, the lines are certainly not a little more blurry – but in a good way.

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Speaking of lines, it seems inevitable that Trek will trickle IsoSpeed technology to lower-priced Domane frames and bikes to be introduced later. What really intrigues us, however, is the possibility of an IsoSpeed-equipped Trek Cronus cyclo-cross bike or even a Superfly 29er hardtail. The IsoSpeed concept clearly has applications outside of road market and its benefits would be even more noticeable in those environments. 2013, perhaps?

Trek have cleverly managed to incorporate the IsoSpeed pivot assembly into the Domane frame without radically impacting the aesthetics.
James Huang/BikeRadar