Giant might be latecomers to the aero bike party, but they’re certainly not lacking in confidence when it comes to the Propel Advanced SL 3. In fact, they’re so confident they’ve challenged Specialized (via Facebook) to a comparison test against the Venge in the all-new Specialized wind tunnel.
We’ve tested the Giant Propel’s rivals and, while their ability to accelerate and hold speed is universally impressive, until now most have suffered compromises. These usually affect the character we appreciate and expect of a bike.
For example, stiffness (or lack of) can be an issue, as can an excessively firm ride. Some also suffer in the weight stakes; all that extra shaping to achieve aero advantages inevitably adds mass.
The Propel, though, feels like the least compromised aero road bike available. This could be down to Giant’s longer development cycle, with more than 80 iterations of the design being investigated, or because they’ve been analysing the competition.
Read Giant’s development notes and you’ll find that the aero-profile down tube broadens and reshapes the way it does because the bike was developed with the idea that a round drinks bottle would be fitted – this is a road bike after all. It’s small details like this that go some way to explaining the Propel’s overall charms.
The Giant SLR stem is light and as solid as a rock when you're riding
The geometry perfectly mirrors that of the Giant TCR, with our large having a long 58.5cm top tube, a metre-long wheelbase and a sharp 73-degree head angle mated to the half-degree slacker seat angle. That means it feels familiar, responsive and sharp, yet the smooth nature over rougher surfaces and ultimate stability at speed make for one of the finest ride experiences we’ve had.
Braking is courtesy of Giant-designed, TRP-made integrated callipers. The swoopy shape mirrors the fork and seatstays. They work like a set of mountain bike-style mini-V-brakes – two arms linked by a cable noodle. The feel through the lever doesn’t offer quite the amount of travel as regular brakes, though out-and-out power feels consistent with the best. It took a few miles to get used to them but once we had we were suitably impressed.
At this price this is an expensive proposition for a bike that ‘only’ comes with mechanical Ultegra. That said, it’s a fine groupset that performs as well as almost any, and otherwise the level of equipment is impressive.
Giant provide most of the kit, including their own 50mm rims
The Contact SLR carbon stem is a lightweight piece of rock-solid carbon, and is matched to a new shape bar with the wing top section being as comfortable as it is aero. Giant’s 50mm-deep carbon wheels are stiff, swift and handle consistently even in stiff crosswinds.
In Giant’s illustrious line-up we’d put the Propel ahead of the TCR for ride comfort, though it weighs more, but the big surprise is that it’s not that far behind the Defy in terms of its smooth ride and cushioning of the rider. Not only is it pretty much our favourite aero bike right now, it’s close to becoming our favourite Giant.
The Propel radiates a lasting impression of truly impressive pace, impeccable manners and race bike responsiveness. The aero optimisation hasn’t compromised its abilities as a bike, it’s just a shame it’s quite so pricey for an Ultegra spec.