Giant Propel Advanced SL Disc

In a word? Fast. That’s the Propel Advanced SL.

You likely recognize the Propel from the Tour de France, where Team Sunweb (formerly Giant-Alpecin) has used it for flat and sprint stages since the bike’s debut in 2013. Michael Matthews won races on a Propel, as did John Degenkolb and Marcel Kittel. When the road is flat, or the finish calls for a kick, the Propel has been the tool for the job.

For 2018, Giant completely re-engineered the bike, drastically changing the shape of the frame tubes and making disc brakes a stock feature. The result is a bicycle that looks and feels like it came from the future.

Every single cable is routed through the integrated stem and into the frame. The Contact SLR aero handlebar is shaped like a wing. The fork crown is devoid of any cables or brake mountings, to ease the flow of air around the front wheel. It just looks incredibly fast.

Out on the road, it feels the same way. Like most aero road bikes, the Propel launches off the line and seems to build to a high cruising speed with little effort. Giant claims its design cheats the wind better than any aero bicycle on the market. We cannot confirm or deny this claim — unfortunately we were not able to test the bike in a wind tunnel — yet it is undeniable that the bicycle felt fast and efficient on flat roads.

Giant credits much of this to the new shape of the frame tubes. Each tube has a rounded front edge with a flat back, a truncated ellipse design that Giant produced using its “AeroSystem Shaping Technology.” Giant claims these tubes help the bicycle deflect wind yaw at greater angles than do other aero bicycles.

The Giant SLR 0 Aero disc wheels (42-millimeter front and 65-millimeter rear) further enhance the aerodynamic properties of this sleek machine.

The Propel also performed well on climbs and tricky descents — terrain where aero bicycles typically struggle. Our XL test bike sported a 73-degree head tube angle, 1,021-millimeter wheelbase, and 405-millimeter chain stays.

There are a few gripes. The Advanced SL has an integrated seat mast, which must be cut to the user’s preferred height. The wing-shaped handlebar cannot be adjusted to accommodate multiple bar angles. Due to the bike’s internal cable routing and integrated stem, replacing the handlebar would create a sizable headache. To some degree, the bicycle requires the rider to mold him or herself to its specifications, not the other way around. But hey, speed requires some compromises — and resources.

We tested the top-end Advanced SL Disc Di2, which retails for $11,530. While that may be out of reach for the majority of cyclists, the Shimano Ultegra-equipped Propel Advanced Disc runs just $3,775. And there are two other price points falling in between, at $7,140 and $5,815.

We hope you enjoyed this online gear selection. For the complete VeloNews Buyer’s Guide, which is only available in the magazine, subscribe to VeloNews, visit your local newsstand, or buy the single issue.