Race Tech

Pro bike: Theo Bos’ Giant Propel Advanced SL

Giant unveiled the Propel Advanced SL ahead of the season-opening Tour Down Under and this machine belongs to Blanco Pro Cycling fast man Theo Bos.

Giant are the world’s biggest manufacturer of bicycles but they bided their time in entering the aero market. Now, after two years in development and 88 prototype iterations, Giant claim the Propel Advanced SL is the world’s fastest aero bike. How so? We ran through the Propel’s key features in this article.

Bos, who won an Olympic sprint silver medal on the track in 2004 before switching to the road, was, along with Mark Renshaw, involved in the development of the Propel Advanced SL, so the Dutchman has had longer to familiarise himself to his machine than most.

Out with Rabobank, in with Blanco Pro Cycling: the Dutch team’s new black and blue paintjob is very easy on the eye 

Narrow is fast, according to Giant: the Propel has a tiny frontal area and is exceptionally sleek, with tube profiles in contrast to the boxy Kammtail design of the Trek Madone 7 or Scott Foil

The Propel’s downtube is shaped to ‘hide’ a water bottle from the wind and all wind tunnel tests were conducted with a dynamic mannequin aboard and one bottle mounted to the frame

The front brake is neatly hidden behind the fork. Blanco riders use custom-machined aluminium brake arms, rather than the stock carbon version specced on production models of the Propel, as it provides a stiffer response but, more importantly, can more easily accommodate wider rim profiles

 The rear brake is hidden behind the seatstays

There’s not much to see back here

Blanco were the only team to have a full fleet of bikes equipped with the latest 11-speed Shimano Dura-Ace Di2 groupset during our visit to Majorca

The latest Dura-Ace chainset has a new four-arm design, which Shimano say is lighter but just as stiff as the old five-arm design. The front and rear mech have also been overhauled and are now much sleeker than the original Dura-Ace Di2 mechs

Shimano also updated their top-of-the-range pedals as part of the latest Dura-Ace overhaul, although the change is more cosmetic than performance related. Bigger riders can, however, now opt for an axle which is 4mm longer than standard

The latest version of Shimano’s Dura-Ace C50 wheels have a wider rim profile to improve aerodynamics and ride comfort

Box-fresh Vittoria Corsa Evo Classic SC tubs

Bos runs a 141mm stem PRO Vibe alloy stem, rather than Giant’s own aero setup. Production models of the Giant Propel Advanced SL3 to be sold in the UK (£4,499) will have a Giant Contact SLR Aero composite handlebar, Giant Contact SLR stem and Giant P-SLR1 Aero WheelSystem 

Bos’ Fizik Arione CX Carbon saddle sits atop an integrated seatpost, which Giant say improves aerodynamics, drops weight and allows for a more forgiving ride


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RoadCyclingUK attended Challenge Majorca as a guest of race sponsor Iberostar, staying at the Iberostar Playa de Muro hotel in Alcudia. For more information visit

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