Vittoria’s cotton-cased tubulars have a reputation for supple feel and excellent grip. The Diamante Pro Radiale is their all-new clincher tyre, and its nylon casing is designed to feel as close to that of cotton as possible.
To achieve this its nylon cord ‘plies’ – the threads holding the sidewalls together – are parallel, rather than having a crossed mesh. A mesh creates more friction, becoming stiffer and reluctant to deform. The Radiale’s parallel threads allow the case to flex more freely.
The tyres are rated up to 145psi. At this pressure they’re fast, but the ride is bullet-hard, the benefits difficult to discern. At 110psi the tyre’s nature is more apparent. It's smooth rolling over changeable surfaces, but its best trait is on corners. Yes it’s a cliché, but the carcass’s supple nature makes it feel like you’re cornering on rails.
Our test tyres have held up well to winter riding. For such a light tyre it’s impressive to see bead-to-bead puncture protection, and with no punctures and no sign of the tread cutting up it looks like it’s working too.
The Diamante is available in 22 and 24mm widths. Vittoria claim that by dropping a millimetre over standard sizes this sheds weight – our 22mm pair weigh 185g each – and improves aerodynamics, though we’d suggest that this depends more on rim width.
We’d also say there’s little discernible difference between these and some narrower 23mm tyres. We noticed a difference fitting them to the latest Zipps and HEDs, where the curvature required to seat them dulled the suppleness, and if running wider rims, we’d suggest the 24mm.
This article was originally published in Cycling Plus magazine.