Cervelo R3 SL

“The Cervélo R3 SL is quite possibly the fastest bike that we have ever tested”
- Cycling Plus

“Quite possibly the most perfect bike to ever grace the tarmac”
- Men’s Health

It’s amazing how many frames claim to be the world’s lightest. Sometimes it’s the weight without paint, or in size 43, or without derailleur hanger, sometimes the claim is simply completely made up. At the same time, the one manufacturer that actually produces the lightest production frame according to independent magazine tests never makes that claim. Why don’t we? Because to us weight is not the primary goal; and because frankly we think the “lightest” claim has been so overdone that it’s got to stop.

To start with the first issue, we don’t focus on weight during the design process. We focus on stiffness, strength, comfort, and safety. Those are the frame characteristics that really matter, and we know that thanks to our superior engineering team, we can design the frames with the best combination of these features. And we know that if we do that correctly, we can achieve all these goals and still make an extremely light frame – even the lightest. But an up-front focus on the weight leads designers to water down the other – much more important – requirements.

So here it is, we have taken the R3 platform – a frame that already offered an incredible stiffness-to-weight ratio, and made it even lighter without sacrificing any of our standards regarding strength and stiffness. That makes the R3 SL the ultimate frame for next year’s Paris-Roubaix, as well as any epic rides you may have in mind. And it is naturally the perfect platform to build a superlight no-holds-barred bike around, undercutting the UCI weight limit even more easily than our other frames.

Squoval downtube

R3 frames ready for assembly at our Toronto facility

The downtube and chainstays of a bicycle frame mostly see lateral bending, even if the frame as a whole is in torsion. Yet virtually all frames on the market sport round or oval downtubes and chainstays. Excellent shapes to counter torsion of those tubes, but not lateral bending. A box section is the best shape to counter lateral bending, which is why we use a box-inspired shape on the Soloist Carbon chainstays (of course the downtube on the Soloist Carbon is TrueAero-shaped for aerodynamic reasons). On the R3, we squared off the box shape even more, leaving only a small ovalization of the shape to boost its buckling strength. This squared-off oval, or Squoval, significantly increases the stiffness-to-weight ratio (STW) of the shape in lateral bending and is used in the chainstays and the downtube. The front and rear of the toptube also use the Squoval shape, but it transitions to oval in the center to counteract the torsional loading in that section.

Smartwall® for Carbon

Upon hearing Smartwall, most people immediately think of Cervélo’s method to obtain excellent lateral stiffness in an TrueAero tube. But the Smartwall principle is universally applicable, not just on aero tubing. After the tube shapes are optimized, the lay-up allows us to further refine the character of the bike. In fact, Squoval tubes are very well suited for the Smartwall application as they have two sides that are very far removed from the central plane – i.e. adding even a small amount of extra material there increases the lateral stiffness significantly. To properly distribute the loads from the Smartwall section into the rest of the tubes, the additional plies are feathered.