Wider wheels and tires are faster aerodynamically, and more comfy besides. S5 arrives specced with 28mm tires but has clearance for approximately a 34mm (calculated) tire. The Aspero is made with gravel racers and go-fasts in your mind. Its aerodynamic tube shapes borrowed from Cervelo's Tour de France dominating R5 https://jackp876cpz9.snack-blog.com/profile