Having considered the frame and components of the second of this season’s winter bike builds on RCUK in our most recent instalment, it’s time to turn our attention to the rolling stock and finishing kit.
For those joining us at part three, here’s a brief recap: thanks to our friends at Specialized UK, Shimano, and Madison, our winter bike build is one of the nicest you’ll find in a day’s ride. A Specialized CruX Carbon Pro frameset takes centre stage, fitted with Shimano’s much-anticipated hydraulic disc brake for road bikes, with the smallest-to-date 140mm rotors. Elsewhere, components from Shimano’s 6870 group complete the line-up. Well, almost.
Our winter ‘cross bike rolls on Shimano’s WH-RX31 wheelset, the Japanese component giant’s first disc-compatible road wheel. It’s a clincher-style rim, and so one with a bead hook to secure the tyre over an innertube. Twenty-four, straight-pull spokes are laced in a two-cross pattern front and rear, and secured to a 24mm deep aluminium rim with alloy nipples, presumably for lightness and corrosion resistance in the case of the last.
The hubs are of the cup-and-cone variety, a system in which Shimano has always placed its trust, despite the popularity of cartridge bearings with other manufacturers. Like all systems, there are pros and cons, and while cup-and-cone can require careful set-up and regular maintenance to prevent damage to the hub shell’s internals , the system retains an allegiance of loyal supporters.
More significant in this context is the presence of Shimano’s CentreLock splines on the non-driveside of the hub flanges. The mechanism represents a mooring for the discs, and while it’s an established technology on Shimano’s mountain bike wheels, the RX31 is the first and only 700c, road-specific disc wheel on which it occurs. The cog-shaped flanges give the hub a robust, even aggressive appearance, and as such look at home in our ‘cross bike.
The wheels are shod with Continental’s CycloXKing tyres, in the slimmer of the two profiles offered. The 32c we’ll be rolling on looks sufficiently rugged for the trails we have in mind, and is UCI compliant; reassuring, no doubt, although we hadn’t planned to tackle the sands of Koksijde. There’s a broader, 35c tyre in the range too.
The tread pattern is arranged in small, square blocks, slightly off-set and angled inwards, with six blocks in total, three either side of the centre line of the rolling surface. Continental describe the ‘studded’ profile as a ‘semi-slick’, and we’ll be reporting on its progress on tarmac as well as trail.
We’ll conclude by turning our attention to the finishing kit. Shimano is well-represented here too, although this time in the guise of its house brand, PRO. In keeping with the standard of the frame and components, this is high-quality stuff: a PRO Vibe 7S handlebar, boasting a claimed weight of 285g. It’s secured by a matching PRO Vibe stem, fashioned from carbon fibre and 7000-series aluminium, and secured with titanium bolts. The integrated ‘puzzle clamp’ closure mechanism looks effective and its polished aluminium face plate is very easy on the eye.
Our winter ‘cross build is ready to roll. Check back next week for our ‘first ride’ report.