Product news: With the new Propel series, Giant is positioning its aero road bikes as a consistently further developed "full system" concept for the new season. Frame, cockpit, wheels, and tires are not optimized in isolation, but rather considered as a cohesive unit to simultaneously reduce air and rolling resistance while improving handling and long-distance comfort. We took a look at the model range at launch.
Giant Propel – “Total Speed System” instead of individual value tuning
Giant describes its development philosophy as a "Total Speed System." At its core is a process that considers the rider, frameset, cockpit, and wheels as a dynamic, integrated system. The goal is to achieve a synergy of reduced overall drag, increased system efficiency, and improved system control. According to Giant, a new dynamic wind tunnel mannequin, manufactured using 3D printing and featuring movable legs, was also used for aerodynamic development, allowing for more realistic conditions across various angles of attack.
Aerodynamics and overall drag: measurable system gain
Giant quantifies the performance leap of the new Propel Advanced SL series compared to the previous generation as an advantage of 18,4 watts, which should equate to 72 seconds faster at 40 km/h over 40 km. This effect is described as the result of a system setup consisting of a redesigned frameset, integrated cockpit, and aero-optimized wheel system and tires.
Weight: lighter SL frame and savings up to the bottle cage
One of the key features of the fourth Propel generation is the weight reduction in the top model. The Propel Advanced SL frame is listed as 45g lighter than the previous generation. Combined with the one-piece Contact SLR Aero Integrated handlebar/stem, the Cadex Max 50 WheelSystem, Cadex Aero tires, and further weight savings "right down to the bottle cages," Giant totals the weight reduction of the Propel Advanced SL 0 at 355g.
Stiffness and efficiency: “Instant speed” through system stiffness
For explosive loads, Giant points to higher stiffness values and efficiency gains compared to the previous generation. The new Giant Propel Advanced SL is described by the manufacturer as significantly more dynamic, and the system development is explicitly focused on converting pedal input into forward motion. Additionally, Giant emphasizes a system approach in which the cockpit and wheel system are understood as part of the stiffness and efficiency benchmarking logic.
Giant Propel – More comfort than speed factor
Giant places a noticeable emphasis on overall comfort, i.e., the ability of the entire system to dampen/cushion bumps and to be able to maintain high speeds for longer.
For the new Giant Propel Advanced SL, this translates to 25% more comfort than before, thanks to the new seatpost. Additionally, the fork and integrated cockpit are said to offer 12,8% more comfort. Tire clearance of up to 32 mm: larger volume tires and lower pressures are intended to reduce rolling resistance and fatigue, and improve control on rough roads.
Key building blocks in cockpit and front-end design
Aerodynamics and service/integration are bundled across several components:
- OverDrive Aero: slim, tapered head tube, D-shaped steerer tube and matching spacers; cables run internally through cockpit, frame and fork.
- Contact SLR Aero Integrated / Contact SL Aero Integrated: one-piece or integrated cockpit solutions with a flat back profile and narrow top section; new geometry with reduced widths on the top section and drops to reduce the rider's shoulder and frontal area.
Cadex wheels and tires: Aero interface as the system core
The perfectly matched Cadex wheel and tire system combines low weight, high stiffness, and optimized aerodynamics for measurable speed under real-world conditions. Developed as a holistic solution comprising rim, spokes, hub, and tire, the Max 50 system delivers maximum efficiency, precise handling, and instant acceleration.
Cadex Max 50 WheelSystem
An integrated system comprising hub, flange, spoke, and aero hub design with a total weight of 1290 grams (including valves and tape). Furthermore, compared to the Cadex Ultra 50, the system offers an additional 2,18 watts of aerodynamic improvement and 5,4% higher stiffness. Combined with the Cadex Aero Tire, this represents a significant upgrade, as the Aero Tire, thanks to its new 240 TPI casing, is up to 55 grams lighter per tire and also achieves 2,8 watts less rolling resistance per wheel. Additionally, wind tunnel tests indicate a further aerodynamic effect from micro-grooves on the tire's sidewall, reducing air resistance by 0,76 watts per wheel.
Aero bottle cage: Detailed optimization across the entire bike
As another example of the attention to detail, Giant cites specific aero bottle cages that are specially designed for the down tube or seat tube and are intended to further reduce overall air resistance.
An overview of the new Giant Propel models
The new Giant Propel range features three frame models. Propel Advanced SL, Propel Advanced Pro and Propel AdvancedThe prices for the bikes range from 11.999 Euros for the Giant Propel Advanced SL 0 with SRAM Red components, compared to the Propel Advanced Pro with, for example, Shimano Di2 for 4999 Euro up to the Propel Advanced 1 also with Shimano Di2 for 4.399 euros.