TOUR BIKES FOR TRI
After another enthralling edition of the Tour de France, we assess the tri credentials of three bikes that helped light up 2018’s race. And they’ve all got disc brakes…
The disc brake debate will, it seems, keep raging for as long as we need to slow down a bike in motion. Discs rule the roost in cyclocross, gravel and increasingly with triathlon-specific bikes, but the pro ranks have been slower to accept this ‘new technology’. This is changing, as restrictions have been lifted to allow riders to choose whether they race on rotor or rim brakes. Trek-Segafredo have said they’ll be using disc-equipped Émondas throughout the Grand Tours and many brands have made similar pronouncements.
Now a few years into road disc development, there are some serious advancements taking place at the sharp end of racing bikes. Two of the brands we’re looking at here, Cervélo and Argon 18, are now producing disc frames that are even lighter than their rim-braked equivalents. This means better braking power without the weight penalty, and goes some way to counter the ‘discs are heavy’ argument. To see how the other arguments stack up, we’re taking a look at three of the best pro-level bikes raced in July’s Tour de France – each of them disc-brake equipped.
Cervélo’s redesign of the legendary R5 came last year. For the first time, the brand took their R Series back to the drawing board to make it more aggressive with sharper handling. The introduction of the disc brake version tweaked the geometry even further, reducing the frameset weight and adding provision to use bigger tyres, should you wish.
It soon saw success with a stage win in the Giro d’Italia underneath Dimension Data’s Omar Fraile. The disc version arrived a little later than the rim brake revision, with Cervélo hoping this new generation R Series flagship will continue the series’ successes – which began in 2003 with the R2.5 winning stages underneath Tyler Hamilton and Carlos Sanchez, and the R3 scoring victory with Fabian Cancellara at Paris-Roubaix in 2006.
Lightweight for big climbing days and compliant enough to cope with the cobbled classics, the R5 has always been the aero-optimised S5’s – as ridden by Mark Cavendish – simpler, more understated cousin.
EYE FOR DETAIL
Cervélo have revised the geometry on the R5, making it more race orientated, with the stack dropping by 8mm
and the reach becoming a little longer. Frame stiffness has increased compared to the previous version, and sees the introduction of Cervélo’s Squoval Max tube shape, which blends a square tube profile with ovalised corners and curved sides, top and bottom, while the term Max denotes improvements in these structures with regards to weight, stiffness and aerodynamics. The biggest surprise comes with the weight – the R5 Disc frame is just 831g, even lighter than its rimbrake counterpart (850g).
The R5’s detail shines through; Cervélo have adopted Focus’ RAT system that’s among the best with its fast-release thru-axle with T-bar end and quarterturn lock and unlock. Cervélo’s taken this design, reworked the adjusting nut to make it a bit more minimal, changed the design of the threaded base (into which the T-bar locks) and changed the location of the spring to give a little more resistance.
Cervélo partnered with Enve for the R5’s wheels, and it’s a fine choice with the 3.4 Discs. Enve vary the depths of their rims, so the rear is deeper at 42mm to serve-up maximum aerodynamic benefit while the front is shallower at 38mm to provide a little more stability in crosswinds.
The equipment on the R5 is as we’d expect, with Dura-Ace Di2 filling duties on shifting and braking, and 160mm rotors front and rear for a brake-feel that’s spot on. The saddle is Fizik’s wellregarded Antares, but only the base model R5. Saddles are a personal choice though, so we don’t mind that it’s not a carbon-railed fancy edition as it may get swapped.
The tyres are Continental’s Grand Prix rather than their flagship GP4000 S IIs but they felt similar in testing: supple, grippy and tough. The newly-lowered front end doesn’t feel overly slammed on our 58cm bike, in fact it feels just right for a bike we’d be happy to ride all day, every day.
On the road, the R5 Disc combines a taut feel with positive power transfer that’s ready to go, and rock-solid rigidity when putting the power down on the flat, getting ahead in a sprint or powering uphill. Ride in the saddle, up on the hoods or over poorly-surfaced roads and you’ll find that the R5 is impressively smooth, and the aerodynamic D-shaped carbon seatpost, with its long, laid-back head, offers heaps of compliance.
You’ll also come away impressed after a descent. The R5’s steering responses are quick enough to make rapid direction changes, yet stable enough to control the bike with some simple weight shifts and the slightest steering inputs. The end result is a modern racer that brings together laser-guided handling, with solid power transfer and some serious smoothness.
“The biggest surprise comes with the weight. The R5 Disc frame is just 831g, even lighter than its rim-brake counterpart”
Argon 18, like their Canadian counterpart Cervélo, have built a reputation for making well-engineered bikes that combine light weight with excellent ride quality and clever design touches. The Gallium Pro hits the lightness mark, and Argon 18 state that this disc brake version of the Gallium Pro is even lighter than the rim-braked model, which itself has a sub 800g frame.
The Gallium has the latest iteration of their press-fit 3D headset system, where interlocking solid parts extend the effective head tube height to allow for perfect positioning. Argon 18 claim that this system keeps more stiffness in the head tube compared to standard spacers, which can leave room for flex. Every frame size has three head tube height options, and we set our medium test bike at 165mm. The 72.7° head angle and 73.5° seat angle add to a race-focused geometry that’s built for World Tours, making the Gallium a pack-leading bike. With its low, slightly forward ride position you feel on top of the pedals – and encouraged to go.
Our test bike, put together by UK Argon 18 distributor I-Ride UK, included a set of recently-launched Token Zenith Ventous carbon clinchers. These 36mm deep rims are wide at 27.4mm, and their aero profile with its 20mm internal dimension shapes the Continental Grand Sport tyres very well. The Tokens roll well, are quick to accelerate and feel feathery on the climbs, making the claimed weight of 1,404g easy to believe.
The wheels lock into place with 12mm thru-axles, and it’s here where again, Argon have scored well. Using the integrated NAILD system, which uses the Locit lever, the large quick-release has another lever set into it. To open, you depress the red inner lever, allowing the black lever to activate. Like Cervélo’s Rapid Axle Technology system, a quarter-turn pulls the axle out. The beauty is that it’s virtually impossible for it to loosen on its own.
The Gallium offers gloriously fine handling with the chassis stiff through the head tube, bottom bracket and chainstays. Above this solid undertray, the Gallium has beautifully smooth compliance making it fantastic for covering ground, fast.
On descents we’d have preferred a 160mm front rotor instead of the 140mm Ice Tech Ultegra fitted. On longer descents we managed to make the front disc pretty vocal, which didn’t happen on the same descents on bikes equipped with 160mm units. Shimano’s Ultegra is used throughout the Gallium which, compared to the well-priced Cube and Cervélo, doesn’t make it as good value. In pure performance terms, Ultegra is every bit the equal of Dura-Ace with electronically assisted shifts that are spot on and a brake-feel that’s every bit as good, but you compromise in the weight stakes and, arguably, a few finishing touches too.
The Gallium Pro’s wonderful ride is balanced by such a clean piece of design that it runs the risk of being overlooked in favour of more flamboyant bikes. Just a few tweaks to the build would take the Gallium Pro Disc from a very good to stunning superbike.
German brand Cube have a well-earned reputation for damn fine bikes at very competitive prices, consistently offering value in high street bike shops that competes with online-only specialists. Their new Aerium C:68 SLT triathlonspecific machine – ridden by Germany’s former iron-distance record holder, Andreas Raelert – has turned heads in 2018, and Cube have an extensive range of tri, gravel and mountain bikes to pick from. Like most of its rivals, Cube offer road bikes in a range of carbon grades and technical build specs, with the pinnacle being the remit of the Litening C:68.
The latest version uses Cube’s advanced twin-mould technology, where two solid pieces are used to form tube shapes, rather than the traditional mould-and-inflated bag method. This makes for better control of the resin-to-carbon ratio, efficient management of imperfections (creases) and better control of the overall structure. The shape maintains the traditional twin triangle design and, while it’s quite simple, we prefer to think of it as understated.
Geometry-wise the Cube follows the classic short, sharp geometry found on a lot of European bikes, and mixes parallel, steep 73.5° angles with a short 991mm wheelbase. The ride position is aggressive with a low 563mm stack (vertical distance between the bottom bracket and top of the head tube) and a long 398mm reach (horizontal distance).
Hit the tarmac and the Cube feels every inch the pro tour superbike. The handling is razor sharp and the short wheelbase offers an incredibly nimble ride through even the most technical twists and turns. Like the Cervélo on test, the SLT is running Shimano’s exemplary Dura-Ace Di2 with a well-placed range of 11-28 combined with a 52/36 chainset. Unlike its rivals, the Cube’s front disc had suffered a knock in transit so we did get a bit of ticking on our first ride out from a slightly bent Ice Tech rotor, but some fettling with a rotor-straightening tool soon sorted it for successive rides.
Cube’s new in-house component line Newmen supplies the slick carbon seatpost, well-shaped carbon bar and minimal alloy stem. The bike should have been shipped with matching Newmen wheels but production delays meant that it came with Dutch wheel brand Scope’s excellent tubeless- compatible R4Ds instead, replete with Schwalbe’s equally impressive Pro One tubeless tyres.
The ride felt firmer than its rivals we tested here, but that was countered somewhat by the great tyres and wheels. Riding the Litening never felt harsh, and the firmness feels well balanced with the sheer speed at which it can be shifted in any direction. The acceleration is particularly impressive thanks to the solidity through the drivetrain. It’s only on the climbs that the Litening doesn’t quite match up to the flyweight Cervélo R5 with its stratospheric ability to shine uphill, but we’re really splitting hairs here because the C:68 SLT is a brilliant all-round performer.
While the Cube isn’t the most refined or lightest of the three on test, we think it’s by far the best value, and would even go so far as to say it’ll be the best value in the whole peloton.
“The short wheelbase offers an incredibly nimble ride through even the most technical twists and turns”