Cervelo S3 Disc

You probably won’t need the little chainring on this bike — we didn’t. Cervelo’s S3d is a purebred race machine that compels you to shift into a harder gear, fold into an aero tuck, and go faster.

Aerodynamics have always been a top priority for Cervelo, and that shows in the S3d’s frame design. From the internal cables to the bladed aero seat tube that hugs the rear wheel to the new fork design, which Cervelo says has 19 grams less drag than an equivalent fork.

Happily, those aero features are folded into a frame that gets the fundamentals right. The S3d’s geometry lends to the bike’s racey feel, with a steep 73.1-degree head tube, a short 148-millimeter head tube, and a low bottom bracket (68 millimeters of drop). The S3d also employs 12-millimeter thru-axles front and rear, in keeping with what seems to be the most consistent industry standard.

The S3d is a bit expensive at $7,400 but it is built with some very capable components. Shimano’s Ultegra Di2 is nearly flawless, as usual, and the flat-mount hydraulic discs only make it better. The Enve carbon wheels are one of the biggest highlights, although we wonder if a slightly deeper rim might be more appropriate on a speedster like this.

While we love the S3d’s fast-and-furious personality, the aero handlebars didn’t work for our testers. The flat tops aren’t easy to grip, and one rider thought they were too wide at the hoods.

On the balance, this Cervelo is still one of the best disc-brake race bikes you can find on a bike shop floor. And yes, it does include a 36-tooth little ring — for recovery days, right?

Component highlights: Shimano Ultegra Di2 drivetrain with hydraulic RS805 brake calipers, Enve SES 3.4 carbon clincher wheels, Cervelo aero AB04 carbon handlebar.