Giant has completely revamped its Propel aero road bike, using what it calls AeroSystem Shaping technology, which means that every tube shape and angle was optimized for minimal drag with a new “truncated ellipse” shape.
The Advanced SL-grade carbon frame is billed as being both ultra-stiff and super light. And its new disc-brake technology is integrated with the frameset, including flat-mount calipers and thru-axles for improved wheel stiffness and braking performance.
The new Giant bike will come in five build options, ranging from the top of the line Propel Advanced SL 0 Disc for $11,300 to the less eye watering Propel Advanced Disc for $3700.
“It’s easy to improve aerodynamic performance by sacrificing stiffness or weight,” explained Giant. “But we committed to key design elements including a larger headtube, downtube and bottom bracket area that we feel are critical to the bike’s efficiency and handling. These decisions help give the Propel Disc an even better stiffness-to-weight ratio.”
Giant says it took three years of experimentation with tube shapes, and hundreds of iterations in CFD and wind-tunnel testing to get where they wanted to be. Press play to learn more and then keep scrolling down to read about the core technologies of the new Propel Advanced SL Disc.
Using its AeroSystem Shaping Technology process, Giant says it took a holistic view of the bike as a complete system, analyzing countless combinations of frameset designs through CFD and wind-tunnel analysis. One of the key breakthroughs is a new truncated ellipse airfoil shape that delivers improved overall aero performance at various wind angles.
They also found that, with proper integration, a disc-brake design can actually improve aerodynamic performance. The final step was to refine the entire system at Aero Concept Engineering in Magny-Cours, France. There they created a new integrated Contact SLR/SL Aero handlebar/stem unit with internal cable routing and an integrated Giant SLR WheelSystem with aero spokes.
The rear wheel has a taller 65mm rim depth, proven in wind-tunnel testing to produce minimal drag. The front wheel, which is more affected by crosswinds, features a shallower 42mm rim. This further boosts the bike’s aerodynamic performance by lessening the effect of crosswinds on the front wheel while also reducing overall drag. To accurately simulate real-world riding conditions, their team of aerodynamics experts created a dynamic mannequin. Other bike manufacturers use static mannequins, but only a dynamic one can accurately replicate the effects of a rider pedaling with various wind angles.
With its new integrated disc-brake technology, the Propel Disc range delivers superior braking power and greater modulation in wet or dry conditions. This was a critical performance demand from the company’s sponsored pro road racers, who typically race for hours on twisting terrain with high-speed descents and cornering before they make the decisive breakaway or sprint for the finish. The result is a bike that not only accelerates and slices through wind faster, but also corners with greater precision and handles better in all types of racing situations.
The frameset of the new Propel Advanced SL Disc, including the new integrated stem and handlebar, is claimed to be lighter than its key competitor, including the Specialized Venge Disc and Trek Madone. Giant says the Propel Advanced SL Disc frame is also stiffer than those competitor bikes.
- Vector Integrated Seatpost: Designed as a key performance factor in the overall frameset, the integrated seatpost saves up to 45 grams compared to standard composite posts, while improving aerodynamics and adding road-smoothing compliance.
- Advanced SL-Grade Composite: Giant’s Professional Grade carbon material is woven in their own composite factory using a proprietary resin formula and our most advanced engineering and construction methods including: Continuous Fiber Technology, CNT Technology and Fusion Process.
- Overdrive 2: Giant’s most advanced steerer tube technology offers improved steering precision. Oversized headset bearings (1 1/2” lower, 1 1/4” upper) and a tapered steerer tube produce superior front-end stiffness.
- Powercore: A massively oversized bottom-bracket/chainstay area features a fully integrated, 86mm wide bottom-bracket design. Asymmetric chainstays provide additional stiffness on the driveside and stability on the non-driveside.
- Ridesense: Giant’s chainstay integrated, wireless data transmitter. The removable transmitter sends wheel speed and cadence information directly to any ANT+ compatible computer.
- Internal Cable Routing: Frame/handlebar/stem feature unique cable porting for sleek, non-cluttered appearance and performance.
- Disc Brake Integration: The frame and fork are engineered specifically for flat-mount disc-brakes, including front and rear 12mm thru-axles for reliable braking performance in all weather and road conditions.
- Contact SLR Aero Bar/Stem: Composite integrated handlebar-and-stem unit improves aero performance with wind-tunnel shaped airfoil design and internal cable routing.
For more info visit www.giant-bicycles.com.