New World Cyclo Cross Champion Marianne Vos's Giant TCX Disc(Image credit: BikeRadar)
The rear hub's largely conventional looks, with 28 J-bend spokes(Image credit: BikeRadar)
Neat mounting for the rear hydraulic caliper and dropout. Like her compatriot, Lars Van Der Haar, Vos uses 140mm disc rotors front and rear(Image credit: BikeRadar)
Marianne Vos and her Dad checking over one of her bikes before another practice lap ahead of today's race(Image credit: BikeRadar)
The bridgeless seat stays offer plenty of clearance and nowhere for mud to snag(Image credit: BikeRadar)
Even with 33mm Dugasts, there's ample space behind the bottom bracket shell, and the wide shell sets the chain stays well apart for excellent muck shedding(Image credit: BikeRadar)
The fork crown too has masses of room(Image credit: BikeRadar)
We've seen these Shimano 35mm 28 hole carbon tubular rims before, but they still have no name and they're still a mystery(Image credit: BikeRadar)
The manganese-railed Fizik Arione is at least black for practicality(Image credit: BikeRadar)
PRO's Vibe 7s bar and the 85mm 30 degree negative rise stem(Image credit: BikeRadar)
One of Vos's other TCX disc machines, which is identical apart from having silver chain rings(Image credit: BikeRadar)
Marianne Vos inspiring some young Dutch fans(Image credit: BikeRadar)
The bike that Vos finished the World Championship on(Image credit: BikeRadar)
The overnight rain made for a major drivetrain test(Image credit: BikeRadar)
The bottom bracket area is suitably vast, utilising the shell's full 90mm width(Image credit: BikeRadar)
…and here it is at its highest point. On paper, introducing more possible means of unshipping a chain for cyclo cross racing seems unwise, but it clearly works(Image credit: BikeRadar)
Demonstrating the difference between the high and low points of the Q rings, this is the point where the chainring is furthest from the front mech…(Image credit: BikeRadar)
Without a frame size small enough to facilitate Vos's low riding position, she uses this negative rise stem(Image credit: BikeRadar)
Vos had three TCX Disc bikes and several with cantilever brakes as back up for the Worlds(Image credit: BikeRadar)
Vos has fully embraced disc brakes, running Shimano's Di2 R785 hydraulic system(Image credit: BikeRadar)
Another look at that stem, which is 85mm long, and a stated -30 degrees(Image credit: BikeRadar)
The clean cantilever-free fork, and some of Dugast's finest Typhoon tubulars. Shortly after we took these, Marianne had all of her bikes swapped over to Dugast Rhinos for the race(Image credit: BikeRadar)
With such a tiny stem, and almost no space beneath it, Shimano's Di2 control box is positioned to one side. The Di2 cable and rear hydraulic hose both run in to the left side of the down tube.(Image credit: BikeRadar)
This version of the TCX still uses conventional quick release skewers, unlike one of the consumer models which features a front thru axle(Image credit: BikeRadar)
The previously unnamed Shimano disc hubs do now at least have a CX75 designation. Note the forward facing dropout(Image credit: BikeRadar)
The unused right side cable entry is filled in to keep the elements out(Image credit: BikeRadar)
The Dura Ace crankset is fitted with Rotor's oval Q rings in Vos's favoured 38/46t combination(Image credit: BikeRadar)
Vos uses 172.5mm cranks for a little exrtra leverage(Image credit: BikeRadar)
Shimano's M980 pedals appear to have been disassembled and sanded smooth on some surfaces(Image credit: BikeRadar)
The effect is more pronounced on the other side(Image credit: BikeRadar)
Note the lack of braking track worn in to the rim, and lack of mud build up on the stays(Image credit: BikeRadar)
At 26, Dutch cycling superstar Marianne Vos convincingly won her seventh elite women’s title at the World Cyclocross Championships in Hoogerheide, Holland, on Saturday. Before she did, we got our hands on one of the bikes she used.
Giant’s TCX Disc has become a familiar sight at the front of the men’s field under the fast-starting Lars Van Der Haar, but for the tech-savvy and technical Vos, her decision to use the disc machine was telling. The TCX Disc has already hit the consumer market, some models with a front thru axle, but Vos’s team bike retains conventional quick release skewers, and even though she runs Shimano’s electronic Dura-Ace Di2, her frame doesn’t have either convertible or specific electrical cable routing.
The most prominent feature of Vos’s TCX is the negative-rise stem. Although she rides the smallest frame size available (50cm/S), she still wanted a lower riding position, and thus this stem was the only option. At 85mm it’s an odd size, but the –30 degree angle is even more unusual, and is one Shimano’s PRO component arm don’t currently offer. Fortunately a Giant Taiwanese manufacturer does. A 42cm PRO Vibe 7s bar, tilted back a little gives a position that is super low when riding on the drops, or low and long when on the hoods.
Shimano’s hydraulic road disc system has been widely reported, and is slowly becoming more common. Here, Vos has 140mm rotors front and rear, fitted to Shimano’s as-yet-unnamed road disc wheels, with their 35mm tubular carbon rims, and 28-hole CX75 hubs, laced two cross with black, bladed J-bend spokes.
The drivetrain is Shimano Dura-Ace Di2 with internal battery, and the addition of a pair of Rotor’s oval shaped Q-Rings, in 38/46, necessitating careful placement of the front derailleur to allow for the oval ring shapes. An 11-28 tooth cassette gives a wide range of gears, and the 172.5mm cranks are relatively lengthy for a rider of her 1.69m height, but give some extra leverage, especially useful in the mud.
The bike we featured had Dugast Typhoon tubulars fitted, which are excellent tyres for fast, intermediate conditions, but after the heavy overnight rain, Rhinos were the only practical option from Dugast’s offerings, and Vos had all her bikes swapped to the grippier mud tyres before embarking on her final course recces. Both tyres are 33mm wide, the maximum allowed under UCI regulations, but the TCX frame still has impressive clearance all round.
A Fizik Arione saddle is fitted on to the TCX’s specific carbon seatpost, whose subtly flattened rear prevents misalignment, but also induces a measure of flex too, being nominally sized as 27.2mm diameter. There are a number of neat finishing touches, such as the filled in right side gear cable opening in the down tube, and small plugs that are fitted flush in each of the frame’s bottle cage boss holes for practicality.
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For such a small bike with carbon rims and tubulars, we expected a little less overall mass, but its 7.98kg complete with pedals, and the undoubtedly heavier disc brake setup is still very respectable, and clearly didn’t hold Vos back, since she won alone 1’07” ahead of second place. When asked following the race, her mechanic said that she only changed bike three times in the four long laps she completed, attesting to the bike’s mud shedding abilities, and the rider’s talent. With such an effective combination, it would be a brave person who’d bet against Vos continuing her reign next year too.
