With the Defy Advanced Pro 0, Giant targets riders who enjoy all-day rides on challenging terrain over mixed surfaces.
The bike largely delivers on this goal. The geometry is intended for a more upright riding position and stable platform with a whopping 205-millimeter head tube, 72.5-degree head tube angle, 73-degree seat tube angle, and 1,022-millimeter wheelbase.
The drivetrain’s wide gearing means long climbs on long days won’t take as much grinding. A 34-tooth chainring combined with a 32-tooth cog in the back is about as generous as you could ask for on a road bike. Unfortunately, Giant’s house-brand tire/wheel combo comes up a bit narrow for our taste, especially on a bike that screams to be taken off the beaten path. The Gavia tubeless tires were 25 millimeters wide, which would be fine if you stick to pavement. If you prefer to mix in some dirt roads, wider rubber is a must.
Overall the bike has a relatively impressive lateral stiffness score. It comes by way of a really stiff bottom bracket (stiffer, in fact, than the Giant TCR Advanced) and a rather flexy head tube, relative to other bikes tested in the lab.
Indeed, the bike feels quite snappy during acceleration, and it’s plenty comfortable for the long haul.
Component highlights: Shimano Ultegra Di2 drivetrain with 50/34 crankset and 11-32 cassette; Shimano RS805 hydraulic disc brakes; Giant SLR 1 Disc WheelSystem