Trek has been using IsoSpeed elastomers in its carbon bikes for years. But in the world of trickle-down technology it was inevitable this accessory would turn up in its aluminium frames — and Trek’s 2018 Domanes are some of the first bikes to get it.
You get less for your money than the similarly priced Specialized Allez, but it might be a worthwhile trade-off if IsoSpeed brings some of the comfort it delivers in the carbon Domanes.
The Domane ALR3 looks fantastic in a rich pillar-box red, but IsoSpeed is the bike’s real USP. Trek says, this “‘decouples’ the seat tube from the top tube, allowing the seat tube to flex… The bike moves with the road while maintaining the feel and efficiency of the traditional road bike design”.
But it’s not smoke and mirrors, as Trek’s palmarès on the pavé of Paris-Roubaix and the gravel-heavy Strade Bianche shows, which are just some of the races won on IsoSpeed-equipped Treks since 2012. It has been influential too, with Lapierre and Wilier among brands with elastomer-equipped road bikes.
The flipside of IsoSpeed is cost, because it’s more complicated and more expensive to manufacture. This means you don’t get Shimano 105 or Tiagra, but 9-speed Sora. It’s an effective groupset though with decent ergonomics, and it does have a pleasingly wide range of gears, which I feel are the right choice on a bike at this price, where it will appeal to the newer rider and the older cyclist returning to the sport.
With my knackered footballer’s knees, I appreciated the smallest 32-tooth sprocket on hillier test rides. It’s noticeably lower than a bike with a 28-tooth bottom gear, and easily worth the price of bigger jumps between gears, which only becomes an issue if you’re competing. One deviation from Sora is the brakes, but the direct-mount Tektro 731s with cartridge blocks proved very effective.
So, are aluminium and IsoSpeed compatible? Yes.
The Domane’s ride is smooth, though this isn’t purely down to IsoSpeed. The wide, tubeless-ready rims and slick 28mm Bontrager rubber contribute their own share of surface-smoothing road-riding goodness. Might 28mm just become the new de facto standard on non-racing road bike? Well, you can run them at lower pressures for greater comfort, there’s little distortion, and no discernible loss in performance.
Through the saddle, this is probably the most comfortable aluminium frame at this price that I’ve ridden, and comparable with carbon. But it’s so subtle that you don’t really notice it; there’s no unwanted flex, no bobbling or weaving, but hit a pothole, scarred tarmac, small or large road bumps and it takes rough edges off very, very effectively, and without hampering the handling.
The geometry, with its slightly relaxed head angle and longer wheelbase, shows that this is a bike built for endurance rather than all-out speed, and compared with other £1,000 bikes, such as the Pinnacle Laterite 3 and Cannondale Synapse Sora AL Disc, the Domane is carrying a little extra weight. But it carries this very well. And though it hasn’t got rack mounts, its neat, discreet eyelets allow you to fit mudguards, which will just about squeeze in with 28mm tyres.
The result is a superb sportive machine or century rider, well geared for the hills and great for poor quality roads.