Specialized's previous Turbo tyre impressed us with its feel and acceleration, but it was prone to cuts and wore more quickly than the competition. This new model has grown in size from 23mm to a non-standard 24mm and weighs a little more – 211g, up from 185g (claimed weight is 205g) – but it's also gained puncture protection and a filed tread.
Specialized have named the rubber 'Gripton', but whatever it's called, the real story is the way the soft, sticky polymer is combined with the supple 220tpi (threads per inch) casing. Unlike most tyres, the grip surface and tread compound extend into the sidewall. This lets you explore cornering grip levels way beyond that of a standard tyre – we haven't found its limits yet.
The Turbo is most impressive over coarse surfaces, when the extra volume increases compliance without any instability or drift from the tyre's crown at speed. Through corners, its suppleness offers near cotton tubular – the best – levels of ride quality. Being a 24, it's well suited to modern wider rim designs; we've switched ours between Zipp Firecrest, Vision Metron and budget alloy rims and it's most impressive when stretched over a wider bead-to-bead design.
In terms of wear, the old model was a tyre you'd only use for race days, but with this compound the durability has improved. Whether it'll be a match for true hardwearing boots like Continental's GP4000s remains to be seen, but after 200 miles under a UK test rider the Turbos are still performing brilliantly. In the US, our test riders have liked the new S-Works Tubos so much we put them on our Dream Bike.
If they continue to hold up and don't wear too quickly, these could be one of the best clinchers available. Our test pair were limited editions to celebrate the Tour of Britain, but aside from the Union Jack graphic, they're the same as the standard model.