Trek Domane SL5 Disc review

Expectations on a £3,000 or $4,000 bike would be for Shimano Ultegra, but Shimano’s latest 105 has 99 per cent of the performance for considerably less upfront cost. The 105 on Trek’s Domane here is matched to minimal R505 flat-mount brakes and rather oversized companion shifter units. Braking is enhanced by IceTech rotors with their distinct cooling fins and steel/aluminium sandwich construction.

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Where this 105 frugality comes good is with the wheelset. The SL5 has some serious hoops in Vision’s carbon disc-specific Metron 40 Ltd Disc. These 1675g, 40mm-deep wheels feature a blunted aero shape, the rim is wide enough to suit the Domane’s 32mm wide-as-standard tyres and the solidity of the build makes for flex-free running on the smooth cartridge bearing-equipped hubs. 

The wheels alone cost £1,700 / US$2,200 /AU$2,960, and that accounts for more than half of the overall price. Suddenly the SL5 Disc doesn’t look so much like an expensive 105 bike, more a great value one with some very special running gear.

On the road, the SL5 feels plush. The Domane’s twin IsoSpeed design features a decoupled rear end for a suspension-like action, and a front system that mirrors the incredible bump swallowing action of the back. You get the most cushioning feel the faster you go and the bumpier the surface. 

The SL5 feels more comfort-driven than the standard braked version, because the extra clearance created by the omission of caliper brakes has allowed Trek to fit huge 32mm rubber, which comes up even bigger when spread across the Metron 40 rims. The SL just crushes road buzz until it’s just not a factor, but you still get enough feedback to judge grip.

The comfort-giving plushness of the tyres does come at a price, meaning the SL5 doesn’t feel as sprightly as slimmer-tyred bikes. The SL’s chassis is so good we think it would be just as impressive on 28s, and you’d shave a few grams.

Mile-eating machine

This isn’t an out-and-out racer, but a superb mile-eating machine. Seldom do you return from four- hour-plus rides as ‘fresh’ as you do on the Domane, with the fatigue coming from your efforts and not the effort you’ve put in coping with vibrations, bumps and discomfort.

At nearly 8.5kg you will find lighter bikes for the same sort of money, but like all great sportive machines the SL5 doesn’t feel heavy. It would be easy to shed some weight if that’s your thing – a lighter carbon bar and skinnier tyres for a start – but we wouldn’t worry about such trivialities and just get out and enjoy the ride.

It’s set up for the dedicated endurance rider, with the big tyres, comfortably cushioned Affinity saddle and get-up-anything 50/34, 11-32 gearing. If all this makes you think that the SL’s going to be dull, think again.

The Domane’s handling is pitched just right, and really shines from the way in which the engineered mechanical compliance from the frame’s decouplers add bags and bags of traction. 

The Domane has the uncanny feel of sitting in and holding its line through the fastest swooping bends, letting you go beyond your usual comfort zones to really stretch your limits.