Giant Propel Advanced SL 0 Review: A Lighter, Faster Aero Road Bike

Introduction

The Giant Propel Advanced SL 0 is the flagship build of a platform that has been in service for roughly four years, so this update arrives with a familiar brief: lighter, stiffer and more aerodynamic. The numbers behind those claims are more interesting than the wording. Giant reports a total saving of 327 grams over the previous model, split between 102 grams from the cockpit, meaning the stem and handlebar, and 225 grams from the frameset.

The aerodynamic claim is just as specific: 6.2 watts faster than the outgoing bike. That gain comes from a group of decisions rather than one headline change, including position-specific bottle cages, flattened tube sections around the frame and a wheelset developed alongside the bike instead of selected from a catalogue.

The complete build came in at 6.79 kilograms on the scales, which is a strong figure for an aero road bike with an integrated cockpit and a full aero package.

The sections below cover where the weight was saved, how the cockpit is put together, what the CADEX 50 Ultra wheels bring to the package and the details worth checking before committing to a purchase at this level.

Who the Giant Propel Advanced SL 0 Is For

This bike suits riders who want a top-tier aero road platform and are comfortable with an integrated front end. It makes the most sense for someone who cares about weight as much as drag, and who wants a cockpit that can still be adjusted without a full hydraulic rebuild.

Fit versatility is a deliberate part of the design. The saddle clamp accepts 25 millimetres of shims for fine adjustment, and Giant includes a second clamp in the box that extends that range to 45 millimetres. The saddle cradle can be flipped to give either zero or 20 millimetres of setback, so position changes do not automatically mean sourcing new parts. That also helps at resale, because a second owner has room to work with.

It is worth knowing that only the Advanced SL gets the integrated seat post. Other models in the Propel range use a conventional seat tube, so riders who prefer a standard post, or who want an easier setup for travel, have alternatives within the same family.

Main Strengths

Three areas stand out: the frameset and cockpit weight savings, the aerodynamic work around the front end and tubes, and the CADEX 50 Ultra wheels that come with the build.

Lighter Frame and Cockpit

The frameset accounts for 225 grams of the total saving, and Giant reworked the seat tube not only to reduce mass but to build in more compliance, which should make for a more comfortable ride over rougher surfaces. The cockpit contributes a further 102 grams, saved across the stem and handlebar.

Giant also addressed one of the more stressful moments of owning an integrated seat post. Cutting a post is difficult to undo, so the shim system described above lets owners set the post conservatively first and fine-tune later, while the extra clamp in the box provides enough range to accommodate a different rider height in the future.

The result is a frame that is meaningfully lighter than before without giving up the fit adjustments that integrated designs often remove.

Aerodynamic Efficiency

The 6.2 watt improvement comes from details that work together. The bottle cages are position-specific, one shaped for the down tube mount and one for the seat tube mount, and they are designed around round bottles rather than proprietary shapes.

Elsewhere, Giant uses truncated aerofoil profiles, which means flattened sections rather than full teardrop shapes. The back of the down tube, the seat stays and the back of the fork legs all carry flat surfaces, and the bridge behind the seat tube is horizontal and flat as well. The thinking is that flat and horizontal lines manage airflow efficiently in these locations.

The front end is where the design feels most practical. Instead of threading hoses through the stem, the hoses run through the handlebar, exit at the rear, pass through the stem and drop down the head tube, with the visible section sitting in a hollowed channel underneath. That keeps them accessible, so adding or removing headset spacers does not become a lengthy brake bleed. The spacers are split as well, which means they can be removed without dismantling the whole assembly.

The trade-off is a D-shaped steerer, which limits the bike to Giant’s own stems. There is a carbon version, fitted to this build, and a more affordable aluminium option. Third-party stems are not an option, but the bar clamp remains 31.8 millimetres, so third-party handlebars are still compatible, and integrated bars can be routed either under the stem or out the back in the same style as the stock setup.

The CADEX 50 Ultra Wheels

The wheels deserve the most attention in this package. These are CADEX 50 Ultra wheels with matching CADEX tyres, developed in conjunction with the frame as a single aerodynamic unit. The rim depth is shallower than many riders expect on a bike like this, but the frame was tested against popular wheelsets from Enve, Zipp and DT Swiss, and this combination came out fastest.

The specification is serious: ceramic bearings in the hubs, carbon fibre straight-pull spokes and hookless rims measuring 22.4 millimetres internally. Because the wheels and tyres were designed together, they should perform as a matched pair rather than as two separate purchases.

CADEX is Giant’s in-house brand, but the wheels are not restricted to Giant frames. They are available as a standalone wheelset, which makes them interesting for riders who want the aero benefit without changing bikes.

Things to Consider Before Buying

The D-shaped steerer is the detail to weigh most carefully. It delivers the clean hose routing and easy adjustment described above, but it also means no third-party stems, now or later. Riders who like to experiment with cockpit length, or who already own a preferred stem, should factor that in.

Pricing is the other open question. Complete-bike pricing was not confirmed, and a build at this level was expected to land in five figures. The wheelset is expected to sell for around £2,750 on its own, a figure that was still to be confirmed. If the wheels are the main draw, that standalone price is worth comparing against the cost of the complete bike.

There is also a visual point. Aero road bikes have converged on very similar shapes, and this one can be difficult to pick out of a lineup of the most popular models. That is not a performance problem, but buyers looking for a design that stands apart from the crowd should know what they are getting.

Buying Advice

Two decisions matter most. The first is whether the integrated cockpit and integrated seat post suit the way you ride. If you swap stems, travel frequently with the bike or simply prefer conventional parts, the other Propel models with a standard seat tube will be easier to live with. If you value a clean front end and the fit range built into the saddle clamp, the Advanced SL 0 delivers both.

The second is the wheels. The CADEX 50 Ultra set is the most distinctive part of this build, and the fact that it is sold separately means you can evaluate it on its own terms. For riders who want a complete, matched aero package and are happy to work within Giant’s cockpit ecosystem, this build makes a strong case.

For everyone else, the honest position is that the Propel Advanced SL 0 rewards buyers who already know their position and their priorities, and who want a very light aero bike with genuinely serviceable cockpit adjustments.

Conclusion

The Giant Propel Advanced SL 0 delivers on its three headline claims with numbers that hold up to scrutiny: 327 grams saved across the frameset and cockpit, 6.2 watts of aerodynamic improvement and a 6.79 kilogram complete build. The practical details matter just as much, from accessible hose routing and split spacers to a saddle clamp that allows real fit adjustment after the post has been cut.

The compromises are clear rather than hidden. Stem choice is limited to Giant’s own options, complete-bike pricing was not confirmed, and the silhouette blends in with a crowded category. The CADEX 50 Ultra wheels are the element most likely to surprise riders, offering a matched wheel and tyre package that proved fastest in testing against well-known alternatives.

For a rider who wants a light, aerodynamic road bike with a cockpit that can still be worked on, this is a compelling flagship.