With the astronomically expensive Rca, Cervélo pushed the engineering limits of frame construction; with the new R5 and R3 road bikes, the company is bringing some of the lessons learned from the Rca project to more reasonable pricepoints.
Video:Cervélo road bikes at Eurobike 2013
R5 frameset and complete builds
- Weight: 830g (56cm)
- Frameset: US$5,000/£3,699
- Complete bikes: Shimano Dura-Ace Di2 (US$9,000/£6,799), Shimano Dura-Ace mechanical (US$7,000/£5,199), SRAM Red 22 (US$7,000/£5,299)
- Availability: October
- Sizes: 48-61cm
With the R5, the new frameset follows the design of the US$10,000 Rca. So that means aero-tuned Squoval 3 tubing with internal cable routing and guides for mechanical or electronic wiring and hydraulic hoses. Squoval is Cervélo’s term for somewhat square, somewhat rounded tubing.
“Loads on a bike frame vary but they are always made of bending and torsion,” said Cervélo product manager Heather Henderson. “For torsion, big and round shapes are good. For bending, big and box shapes better resist loads. Our engineers said, ‘Let’s use both.’”
Squoval 3 is the result of hundreds of hours of engineering
As the name implies, Squoval 3 is the third iteration of this mixed-shape concept, with rounded corners letting stress forces ‘flow’ and preventing stress risers, and additional material used on the sides of the tubes where the greatest loads tend to be.
New for Squoval 3 is the addition of a rounded profile for some leading edges, adding to a claimed 7.4 watt reduction in drag compared to Squoval 2. Cervélo claims that a bike frame accounts for about nine percent of the total rider/bike drag, and the company measures savings at 40kph.
While that level of aerodynamic efficiency might not be noticeable to the rider, Cervélo hopes the increases in bottom bracket and head tube stiffness will be, along with a new fork design that beefs up lateral stiffness while introducing more fore/aft movement for comfort.
The R5 is a more down-to-earth version of the Rca
Speaking of comfort, Cervélo refuses to quantify the top-down movement of its frames. While the engineering-centric company is quick to exhaustively measure the minutiae of its products (putting the ‘finite’ in ‘finite element’ analysis), Cervélo declines to specify vertical movement at the fork, seatpost or chainstays.
“We don’t feel comfortable saying deflection equals comfort,” Henderson said, adding that the company is certainly working behind the scenes to define a comfort metric of some sort.
In any event, the new R5 seatstays are claimed to be more compliant than before, and the seatpost diameter has dropped back down to 27.2mm from 31.6mm.
Cervélo is holding the slender line with its trademark seatstays
Also arriving soon (projected availability October) is a revamp of the Cervélo R3. Like the R5, the bike also now features the Squoval 3 tube profiles of the Rca, with internal routing. The claimed 980g frame will be available as a frameset (£1,699/US$TBA) or as a complete bike in two Ultegra builds (mechanical at £3,099/US$3,700 and Di2 at £4,199/US$TBA).
Coming in 48-61cm sizes, the geometry is the same as it is for all bikes across the R series, but the R3 gets a different fork.
The Cervélo R3 comes as a frame or one of two complete Shimano Ultegra bikes
While the tube profiles and routing options trickle down from the Rca, a few top-end features do not. The Nanovate metal treatment that wraps the steerer of the Rca fork with a thin but incredibly strong layer of nickel is cost prohibitive for use on the R5 or R3, said Cervélo co-founder Phil White.
“Logistics rule out Nanovate on the forks,” he said. “They are made in Asia, and to have them shipped to Toronto for the coating, then back to Asia for assembly, then on to their final market… We just couldn't make that work. We would like to see NanoNickel used in other places in the frame. But right now it’s only done on the Rca and only done in Toronto.”
Also, the specific bottom bracket area design that contributes to the Rca’s burly stiffness at 667g cannot be completely transferred over to the R5 or R3 frames. “What we do on the Rca is quite special,” White said.
For more information on Cervélo see www.cervelo.com, and stay tuned for a first ride review of the R5 on BikeRadar.