Cervélo’s R3 is without doubt one of the best racing frames currently available. It’s a heady mix of aggressive geometry and super-low weight, all wrapped up in a whip-fast-handling machine. In taking the R3 into the disc era, Cervélo has been careful in trying to retain that character.
The R3 Disc’s rear end has been redesigned; the slender seatstays now flow all the way into the seat-tube, giving a much wider, stiffer platform than the existing R3’s monostay design. The seatstays and chainstays are asymmetric, with the disc side’s seatstay joining the chainstay behind the thru-axle, with the mech side’s seatstay meeting in line with the axle.
The other benefit of that wider footprint comes when you point the bike downhill and really exploit the R3’s handling qualities
By using a custom spec FSA SL-K chainset with a 5mm offset to ensure the correct chainline, the R3 has managed to maintain short 405mm chainstays rather than having to shift to the 415mm recommended by disc brake manufacturers. This should help retain the bike’s race-ready handling while keeping the improved braking offered by discs. The rear chainstays look particularly minimal and the R3 wears flat-mount standard callipers.
On the road the R3 feels every inch as rapid and nimble as its rim-braked cousin, and at 7.94kg for this Ultegra-equipped model it’s not exactly a heavyweight. On rolling, twisty terrain the R3 Disc is a blast, it’s quick to accelerate and sharp to turn, but the most surprising aspect — given its racy credentials — is the increased comfort.
By eschewing standard brakes and redesigning the back end, and plugging in a disc-specific fork, Cervélo has been able to switch to wide HED Ardennes Plus disc wheels and fit slightly larger 25mm Continental Grand Sport tyres. This adds a layer of cushioning that’s most welcome on poor surfaces.
140mm rotors do the braking business, but we’d have preferred bigger: David Caudery / Immediate Media
The other benefit of that wider footprint comes when you point the bike downhill and really exploit the R3’s handling qualities. Shimano’s RS805 brakes offer total control over your downward velocity, and the tyres just grip and grip as you push harder into every apex. In an ideal world we’d have preferred a 160mm front rotor, as the 140mm one fitted produced a bit of noise once up to running temperatures and under harder braking situations.
Going uphill on the R3 is a similarly rewarding experience as the short wheelbase, light handling and decent gear range all serve to make you a confident climber, especially when you know just how much fun it’s going to be when you crest a rise and head back down.
The R3’s only downside is the price; the frame and fork are stunning, the Ultegra drivetrain — with the classy addition of that custom-spec SL-K carbon chainset — is superb, and the RS805 brakes offer totally dependable performance. But, £3,799 is still a lot to pay, especially when you consider you can get a similarly specced R3 with rim brakes for £800 less, even if that bike’s Mavic Aksiums aren’t quite a match for the test bike’s wider HEDs.
We would still highly recommend the R3 Disc, as it instils all of the sublime character of the standard R3, but adds even better high-speed control thanks to the addition of some seriously good stoppers.