Unreleased Giant Propel with all-new Cadex tubular wheels breaks cover at the Tour de France

First spotted on Tony Martin's Instagram earlier this month, the all-new Giant Propel has broken cover at the Tour de France - and Cycling Weekly is the first to get close to it with these photos of Luke Durbridge's Team BikeExchange-Jayco bike by Dan Cavallari.

Not only that, but the team is using as-yet-unreleased Cadex 50mm tubular wheels, which looks like a significant departure from the tubeless, hookless technology formerly championed by Giant's high-performance wheel brand.

We asked Giant if it could share any information about the new Tour de France bike, but were told the brand was still a few weeks away from the launch. 

What we do know for sure is that Giant's flagship aero bike will still be called 'Propel' because the model name appears in small lettering on the top tube just behind the stem.

Also following model-naming convention, the pro-level bike will be called 'Advanced SL' - which can be read on the inside of the chainstay.

The biggest difference between the outgoing Propel and the new one is the tube shapes, particularly towards the rear of the bike.

The new Propel appears to be a much wispier version that combines elements of an aero and a climbing bike.  

The formerly deep, aero tubing has been slimmed right down to almost Giant TCR levels: the integrated seatmast and seat tube in particular are now so shallow that a rear-wheel cutaway is not even necessary.

Meanwhile the head tube is much deeper than before, something we're seeing with other new race bikes such as the Canyon Ultimate and the Cervelo S5, and the down tube too looks deep, even if not quite as deep as before.

The Propel's horizontal top tube has been retained but the seatstays have been considerably dropped so that they're now parallel with the down tube.

Of course, since Durbridge is tall at 6ft 2in (1.87m) and this bike is likely to be a size large, it’s possible that the bigger frame gives the impression of a more dramatic drop.

Durbridge is running a 12-speed Shimano Dura-Ace Di2 drivetrain with a 54/42 chainring combination up front.  

The cockpit is not the Contact SL stem and SLR bar of the old Propel, as debuted at the Tour de France in 2017, but Giant has kept bar and stem separate, resisting the urge to go all-in with an aero but impractical one-piece front end.

Naturally the cables are all completely integrated - the outgoing Propel was one of the early aero bikes to neatly accomplish this.

Durbridge is using a Fouriers computer mount: these are made especially to integrate with Giant stem faceplates.

Cadex wheels are offered in three depths - 36mm, 42mm or 65mm - but Durbridge's don't look to be any of those. A small sticker suggests they're 50mm and there's no tubeless valve in evidence, either - Cadex generally champions tubeless, hookless technology. 

It might appear to be a one-off team-edition tubular wheelset, but since team equipment has to be commercially available within six months of being used, these must be prototypes - so we're expecting an imminent Cadex launch as well as one to launch the new Giant Propel.