As well as completely redesigning its flagship S5 aero race bike, Cervelo has also taken the time to update its more affordable aero bike, the S3. The changes contribute to the new bike being “102g faster” than the current model, according to Cervelo’s wind tunnel testing claims.
The S3 takes many of the aero lessons of the S5 but dials it back a little, so no funky V-shaped stem and bonkers handlebar. And unlike the S5, which is only available with disc brakes, the S3 offers a choice of rim or disc brakes.
While the S5 grabbed all the headlines, the S3 is actually more interesting because the company claims to have made even bigger aero savings, reducing drag by 13 watts with the new S3 Disc compared to the previous version, and 7 watts for the new rim brake model. That compares to a 5 watt reduction on the S5.
Much of the development has concentrated on the front of the bike. There’s a regular fork, a new aero stem and handlebar, the latter routing the cables and brake hoses directly into the frame, providing a clean appearance with no exposed cabling.
To enable the internal routing, a special steerer tube has been developed with large slots for cables and hoses to be passed through. This new AB09 handlebar comes in four widths (38 to 44cm) and ST029 stem comes in 80 to 130mm lengths.
I wasn’t a huge fan of the aero handlebar on the S3 Disc I tested last year, the new design looks an ergonomic improvement with a more conventional shape. Better looking too, I might add.
The rest of the frame has been refined as well. The down tube has been placed lower and now wraps around the front wheel, much like the S5. This, says Cervelo, improves air flow over the frame. It’s the same with the seat tube as well, it wraps around the rear wheel, and there’s an aero seatpost with an internal seat clamp. To provide some comfort the rear stays have been designed to provide vibration damping.
As well as improving the aero performance, Cervelo has also boosted frame stiffness, particularly around the bottom bracket for that all-important power transfer when sprinting for a KOM or finish line. It’s a lighter frame as well, a claimed 68g has been shaved off the disc brake version while the rim brake frame sees no weight difference. Weight is a claimed 1,100g for a size 56cm.
The disc brake S3 uses the now common 12mm thru-axles with flat mount interface brakes, and fully internal brake hose routing. The rim brake bike uses direct mount callipers on the front of the fork and at the top of the skinny seatstays, and 9mm quick release axles.
There’s been no change to the geometry, as there has been with the S5, so the numbers from the previous model are carried over to the new frame. The S3 offers a slightly less aggressive fit with a taller stack and shorter reach then the S5, making it a good choice for non-professionals who might want a bit of real-world comfort.
There will be four models available, basically, it comes down to mechanical or electronic Ultegra and disc or rim brakes. Prices will start at €3,999 rising to €6,399, and there’ll be a frameset option from €2,999. We don’t have UK prices yet but will update this story as and when we get them.
More info at www.cervelo.com
David has worked on the road.cc tech team since July 2012. Previously he was editor of Bikemagic.com and before that staff writer at RCUK. He's a seasoned cyclist of all disciplines, from road to mountain biking, touring to cyclo-cross, he only wishes he had time to ride them all. He's mildly competitive, though he'll never admit it, and is a frequent road racer but is too lazy to do really well. He currently resides in the Cotswolds.