GRAND PRIXX 4000 S2

£49.95 www.conti-tyres.co.uk

No other tyre here enjoys such a glowing reputation as the 217g GP4000 S2. Not only is it loved by road racers and triathletes for its speed (rolling resistance is 32.0 watts), grip and confident cornering, it’s also cherished by aero wheel engineers because, uniquely, it inflates into an egg shape rather than round, making a more effective combined airfoil with a wheel. This is worth a couple of watts, depending on your wheels, which potentially makes this the fastest overall tyre, especially for your front wheel. Its egg shape benefits cornering grip but slightly alters your bike’s handling, so confident descenders stand to gain the most. It’s 330TPI (threads per inch), the highest here, but its suppleness is only middling. Continental also make the more specialist GP TT clincher, but it’s delicate and wears fast, so for race day only.